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-rw-r--r--src/northbridge/intel/e7505/Kconfig14
-rw-r--r--src/northbridge/intel/e7505/Makefile.inc10
-rw-r--r--src/northbridge/intel/e7505/e7505.h78
-rw-r--r--src/northbridge/intel/e7505/memmap.c53
-rw-r--r--src/northbridge/intel/e7505/northbridge.c82
-rw-r--r--src/northbridge/intel/e7505/raminit.c1718
-rw-r--r--src/northbridge/intel/e7505/raminit.h24
-rw-r--r--src/northbridge/intel/e7505/romstage.c19
8 files changed, 1998 insertions, 0 deletions
diff --git a/src/northbridge/intel/e7505/Kconfig b/src/northbridge/intel/e7505/Kconfig
new file mode 100644
index 0000000000..4a54bc076d
--- /dev/null
+++ b/src/northbridge/intel/e7505/Kconfig
@@ -0,0 +1,14 @@
+# SPDX-License-Identifier: GPL-2.0-only
+
+config NORTHBRIDGE_INTEL_E7505
+ bool
+
+if NORTHBRIDGE_INTEL_E7505
+
+config NORTHBRIDGE_SPECIFIC_OPTIONS
+ def_bool y
+ select NO_ECAM_MMCONF_SUPPORT
+ select HAVE_DEBUG_RAM_SETUP
+ select NO_CBFS_MCACHE
+
+endif
diff --git a/src/northbridge/intel/e7505/Makefile.inc b/src/northbridge/intel/e7505/Makefile.inc
new file mode 100644
index 0000000000..29ac4379cf
--- /dev/null
+++ b/src/northbridge/intel/e7505/Makefile.inc
@@ -0,0 +1,10 @@
+ifeq ($(CONFIG_NORTHBRIDGE_INTEL_E7505),y)
+
+ramstage-y += northbridge.c
+ramstage-y += memmap.c
+
+romstage-y += romstage.c
+romstage-y += raminit.c
+romstage-y += memmap.c
+
+endif
diff --git a/src/northbridge/intel/e7505/e7505.h b/src/northbridge/intel/e7505/e7505.h
new file mode 100644
index 0000000000..b429c70ba4
--- /dev/null
+++ b/src/northbridge/intel/e7505/e7505.h
@@ -0,0 +1,78 @@
+/* SPDX-License-Identifier: GPL-2.0-or-later */
+
+/*
+ * e7505.h: PCI configuration space for the Intel E7501 memory controller
+ */
+
+#ifndef NORTHBRIDGE_INTEL_E7505_E7505_H
+#define NORTHBRIDGE_INTEL_E7505_E7505_H
+
+/************ D0:F0 ************/
+// Register offsets
+#define SMRBASE 0x14 /* System Memory RCOMP Base Address Register, 32 bit? */
+#define MCHCFGNS 0x52 /* MCH (scrubber) configuration register, 16 bit */
+
+#define PAM_0 0x59
+
+#define DRB_ROW_0 0x60 /* DRAM Row Boundary register, 8 bit */
+#define DRB_ROW_1 0x61
+#define DRB_ROW_2 0x62
+#define DRB_ROW_3 0x63
+#define DRB_ROW_4 0x64
+#define DRB_ROW_5 0x65
+#define DRB_ROW_6 0x66
+#define DRB_ROW_7 0x67
+
+#define DRA 0x70 /* DRAM Row Attributes registers, 4 x 8 bit */
+#define DRT 0x78 /* DRAM Timing register, 32 bit */
+#define DRC 0x7C /* DRAM Controller Mode register, 32 bit */
+#define DRDCTL 0x80 /* DRAM Read Timing Control register, 16 bit? (if similar to 855PM) */
+#define CKDIS 0x8C /* Clock disable register, 8 bit */
+#define SMRAMC 0x9D
+#define ESMRAMC 0x9E
+#define APSIZE 0xB4
+#define TOLM 0xC4 /* Top of Low Memory register, 16 bit */
+#define REMAPBASE 0xC6 /* Remap Base Address register, 16 bit */
+#define REMAPLIMIT 0xC8 /* Remap Limit Address register, 16 bit */
+#define SKPD 0xDE /* Scratchpad register, 16 bit */
+#define DVNP 0xE0 /* Device Not Present, 16 bit */
+#define MCHTST 0xF4 /* MCH Test Register, 32 bit? (if similar to 855PM) */
+
+// CAS# Latency bits in the DRAM Timing (DRT) register
+#define DRT_CAS_2_5 (0<<4)
+#define DRT_CAS_2_0 (1<<4)
+#define DRT_CAS_MASK (3<<4)
+
+// Mode Select (SMS) bits in the DRAM Controller Mode (DRC) register
+#define RAM_COMMAND_NOP (1<<4)
+#define RAM_COMMAND_PRECHARGE (2<<4)
+#define RAM_COMMAND_MRS (3<<4)
+#define RAM_COMMAND_EMRS (4<<4)
+#define RAM_COMMAND_CBR (6<<4)
+#define RAM_COMMAND_NORMAL (7<<4)
+
+#define DRC_DONE (1 << 29)
+
+// RCOMP Memory Map offsets
+// Conjecture based on apparent similarity between E7501 and 855PM
+// Intel doc. 252613-003 describes these for 855PM
+
+#define SMRCTL 0x20 /* System Memory RCOMP Control Register? */
+#define DQCMDSTR 0x30 /* Strength control for DQ and CMD signal groups? */
+#define CKESTR 0x31 /* Strength control for CKE signal group? */
+#define CSBSTR 0x32 /* Strength control for CS# signal group? */
+#define CKSTR 0x33 /* Strength control for CK signal group? */
+#define RCVENSTR 0x34 /* Strength control for RCVEnOut# signal group? */
+
+/************ D0:F1 ************/
+// Register offsets
+#define FERR_GLOBAL 0x40 /* First global error register, 32 bits */
+#define NERR_GLOBAL 0x44 /* Next global error register, 32 bits */
+#define DRAM_FERR 0x80 /* DRAM first error register, 8 bits */
+#define DRAM_NERR 0x82 /* DRAM next error register, 8 bits */
+
+/************ D1:F0 ************/
+
+#define APSIZE1 0x74
+
+#endif /* NORTHBRIDGE_INTEL_E7505_E7505_H */
diff --git a/src/northbridge/intel/e7505/memmap.c b/src/northbridge/intel/e7505/memmap.c
new file mode 100644
index 0000000000..b1ac3d1124
--- /dev/null
+++ b/src/northbridge/intel/e7505/memmap.c
@@ -0,0 +1,53 @@
+/* SPDX-License-Identifier: GPL-2.0-only */
+
+// Use simple device model for this file even in ramstage
+#define __SIMPLE_DEVICE__
+
+#include <device/pci_ops.h>
+#include <arch/romstage.h>
+#include <cbmem.h>
+#include <cpu/x86/mtrr.h>
+#include <program_loading.h>
+#include "e7505.h"
+
+void *cbmem_top_chipset(void)
+{
+ const pci_devfn_t mch = PCI_DEV(0, 0, 0);
+ uintptr_t tolm;
+
+ /* This is at 128 MiB boundary. */
+ tolm = pci_read_config16(mch, TOLM) >> 11;
+ tolm <<= 27;
+
+ return (void *)tolm;
+}
+
+void northbridge_write_smram(u8 smram);
+
+void northbridge_write_smram(u8 smram)
+{
+ const pci_devfn_t mch = PCI_DEV(0, 0, 0);
+ pci_write_config8(mch, SMRAMC, smram);
+}
+
+void fill_postcar_frame(struct postcar_frame *pcf)
+{
+ uintptr_t top_of_ram;
+
+ /*
+ * Choose to NOT set ROM as WP cacheable here.
+ * Timestamps indicate the CPU this northbridge code is
+ * connected to, performs better for memcpy() and un-lzma
+ * operations when source is left as UC.
+ */
+
+ pcf->skip_common_mtrr = 1;
+
+ /* Cache RAM as WB from 0 -> CACHE_TMP_RAMTOP. */
+ postcar_frame_add_mtrr(pcf, 0, CACHE_TMP_RAMTOP, MTRR_TYPE_WRBACK);
+
+ /* Cache CBMEM region as WB. */
+ top_of_ram = (uintptr_t)cbmem_top();
+ postcar_frame_add_mtrr(pcf, top_of_ram - 8*MiB, 8*MiB,
+ MTRR_TYPE_WRBACK);
+}
diff --git a/src/northbridge/intel/e7505/northbridge.c b/src/northbridge/intel/e7505/northbridge.c
new file mode 100644
index 0000000000..08ac122243
--- /dev/null
+++ b/src/northbridge/intel/e7505/northbridge.c
@@ -0,0 +1,82 @@
+/* SPDX-License-Identifier: GPL-2.0-only */
+
+#include <assert.h>
+#include <console/console.h>
+#include <device/pci_ops.h>
+#include <device/device.h>
+#include <device/pci.h>
+#include <cpu/cpu.h>
+
+#include "e7505.h"
+
+static void mch_domain_read_resources(struct device *dev)
+{
+ int idx;
+ unsigned long tolmk;
+ uint64_t tom, remapbase, remaplimit;
+ struct device *mc_dev;
+
+ pci_domain_read_resources(dev);
+
+ mc_dev = pcidev_on_root(0, 0);
+ if (!mc_dev)
+ die("Could not find MCH device\n");
+
+ tolmk = pci_read_config16(mc_dev, TOLM) >> 11;
+ tolmk <<= 17;
+
+ tom = pci_read_config8(mc_dev, DRB_ROW_7);
+ tom <<= 26;
+
+ /* Remapped region with a 64 MiB granularity in register
+ definition. Limit is inclusive, so add one. */
+ remapbase = pci_read_config16(mc_dev, REMAPBASE) & 0x3ff;
+ remapbase <<= 26;
+
+ remaplimit = pci_read_config16(mc_dev, REMAPLIMIT) & 0x3ff;
+ remaplimit += 1;
+ remaplimit <<= 26;
+
+ /* Report the memory regions */
+ idx = 10;
+ ram_resource_kb(dev, idx++, 0, tolmk);
+ mmio_resource_kb(dev, idx++, 0xa0000 / KiB, (0xc0000 - 0xa0000) / KiB);
+
+
+ ASSERT(tom == remapbase);
+ upper_ram_end(dev, idx++, remaplimit);
+}
+
+static void mch_domain_set_resources(struct device *dev)
+{
+ assign_resources(dev->link_list);
+}
+
+static struct device_operations pci_domain_ops = {
+ .read_resources = mch_domain_read_resources,
+ .set_resources = mch_domain_set_resources,
+ .scan_bus = pci_domain_scan_bus,
+ .ops_pci = &pci_dev_ops_pci,
+};
+
+
+static struct device_operations cpu_bus_ops = {
+ .read_resources = noop_read_resources,
+ .set_resources = noop_set_resources,
+ .init = mp_cpu_bus_init,
+};
+
+static void enable_dev(struct device *dev)
+{
+ /* Set the operations if it is a special bus type */
+ if (dev->path.type == DEVICE_PATH_DOMAIN) {
+ dev->ops = &pci_domain_ops;
+ } else if (dev->path.type == DEVICE_PATH_CPU_CLUSTER) {
+ dev->ops = &cpu_bus_ops;
+ }
+}
+
+struct chip_operations northbridge_intel_e7505_ops = {
+ CHIP_NAME("Intel E7505 Northbridge")
+ .enable_dev = enable_dev,
+};
diff --git a/src/northbridge/intel/e7505/raminit.c b/src/northbridge/intel/e7505/raminit.c
new file mode 100644
index 0000000000..5387d4df04
--- /dev/null
+++ b/src/northbridge/intel/e7505/raminit.c
@@ -0,0 +1,1718 @@
+/* SPDX-License-Identifier: GPL-2.0-only */
+
+/* This was originally for the e7500, modified for e7501
+ * The primary differences are that 7501 apparently can
+ * support single channel RAM (i haven't tested),
+ * CAS1.5 is no longer supported, The ECC scrubber
+ * now supports a mode to zero RAM and init ECC in one step
+ * and the undocumented registers at 0x80 require new
+ * (undocumented) values determined by guesswork and
+ * comparison w/ OEM BIOS values.
+ * Steven James 02/06/2003
+ */
+
+#include <stdint.h>
+#include <device/pci_def.h>
+#include <arch/io.h>
+#include <device/mmio.h>
+#include <device/pci_ops.h>
+#include <device/smbus_host.h>
+#include <lib.h>
+#include <commonlib/helpers.h>
+#include <console/console.h>
+#include <assert.h>
+#include <spd.h>
+#include <sdram_mode.h>
+#include <timestamp.h>
+
+#include "raminit.h"
+#include "e7505.h"
+
+/*-----------------------------------------------------------------------------
+Definitions:
+-----------------------------------------------------------------------------*/
+
+#if CONFIG(DEBUG_RAM_SETUP)
+#define RAM_DEBUG_MESSAGE(x) printk(BIOS_DEBUG, x)
+#define RAM_DEBUG_HEX32(x) printk(BIOS_DEBUG, "%08x", x)
+#define RAM_DEBUG_HEX8(x) printk(BIOS_DEBUG, "%02x", x)
+#else
+#define RAM_DEBUG_MESSAGE(x)
+#define RAM_DEBUG_HEX32(x)
+#define RAM_DEBUG_HEX8(x)
+#endif
+
+#define E7501_SDRAM_MODE (SDRAM_BURST_INTERLEAVED | SDRAM_BURST_4)
+#define SPD_ERROR "Error reading SPD info\n"
+
+#define MCHDEV PCI_DEV(0, 0, 0)
+#define RASDEV PCI_DEV(0, 0, 1)
+#define AGPDEV PCI_DEV(0, 1, 0)
+#define D060DEV PCI_DEV(0, 6, 0)
+
+// NOTE: This used to be 0x100000.
+// That doesn't work on systems where A20M# is asserted, because
+// attempts to access 0x1000NN end up accessing 0x0000NN.
+#define RCOMP_MMIO ((u8 *)0x200000)
+
+struct dimm_size {
+ unsigned long side1;
+ unsigned long side2;
+};
+
+static const uint32_t refresh_frequency[] = {
+ /* Relative frequency (array value) of each E7501 Refresh Mode Select
+ * (RMS) value (array index)
+ * 0 == least frequent refresh (longest interval between refreshes)
+ * [0] disabled -> 0
+ * [1] 15.6 usec -> 2
+ * [2] 7.8 usec -> 3
+ * [3] 64 usec -> 1
+ * [4] reserved -> 0
+ * [5] reserved -> 0
+ * [6] reserved -> 0
+ * [7] 64 clocks -> 4
+ */
+ 0, 2, 3, 1, 0, 0, 0, 4
+};
+
+static const uint32_t refresh_rate_map[] = {
+ /* Map the JEDEC spd refresh rates (array index) to E7501 Refresh Mode
+ * Select values (array value)
+ * These are all the rates defined by JESD21-C Appendix D, Rev. 1.0
+ * The E7501 supports only 15.6 us (1), 7.8 us (2), 64 us (3), and
+ * 64 clock (481 ns) (7) refresh.
+ * [0] == 15.625 us -> 15.6 us
+ * [1] == 3.9 us -> 481 ns
+ * [2] == 7.8 us -> 7.8 us
+ * [3] == 31.3 us -> 15.6 us
+ * [4] == 62.5 us -> 15.6 us
+ * [5] == 125 us -> 64 us
+ */
+ 1, 7, 2, 1, 1, 3
+};
+
+#define MAX_SPD_REFRESH_RATE (ARRAY_SIZE(refresh_rate_map) - 1)
+
+// SPD parameters that must match for dual-channel operation
+static const uint8_t dual_channel_parameters[] = {
+ SPD_MEMORY_TYPE,
+ SPD_MODULE_VOLTAGE,
+ SPD_NUM_COLUMNS,
+ SPD_NUM_ROWS,
+ SPD_NUM_DIMM_BANKS,
+ SPD_PRIMARY_SDRAM_WIDTH,
+ SPD_NUM_BANKS_PER_SDRAM
+};
+
+ /* Comments here are remains of e7501 or even 855PM.
+ * They might be partially (in)correct for e7505.
+ */
+
+ /* (DRAM Read Timing Control, if similar to 855PM?)
+ * 0x80 - 0x81 documented differently for e7505
+ * This register has something to do with CAS latencies,
+ * possibly this is the real chipset control.
+ * At 0x00 CAS latency 1.5 works.
+ * At 0x06 CAS latency 2.5 works.
+ * At 0x01 CAS latency 2.0 works.
+ *
+ * This is still undocumented in e7501, but with different values
+ * CAS 2.0 values taken from Intel BIOS settings, others are a guess
+ * and may be terribly wrong. Old values preserved as comments until I
+ * figure this out for sure.
+ * e7501 docs claim that CAS1.5 is unsupported, so it may or may not
+ * work at all.
+ * Steven James 02/06/2003
+ *
+ * NOTE: values now configured in configure_e7501_cas_latency() based
+ * on SPD info and total number of DIMMs (per Intel)
+ */
+
+ /* FDHC - Fixed DRAM Hole Control ???
+ * 0x58 undocumented for e7505, memory hole in southbridge configuration?
+ * [7:7] Hole_Enable
+ * 0 == No memory Hole
+ * 1 == Memory Hole from 15MB to 16MB
+ * [6:0] Reserved
+ */
+
+ /* Another Intel undocumented register
+ * 0x88 - 0x8B
+ * [31:31] Purpose unknown
+ * [26:26] Master DLL Reset?
+ * 0 == Normal operation?
+ * 1 == Reset?
+ * [07:07] Periodic memory recalibration?
+ * 0 == Disabled?
+ * 1 == Enabled?
+ * [04:04] Receive FIFO RE-Sync?
+ * 0 == Normal operation?
+ * 1 == Reset?
+ */
+
+/* DDR RECOMP tables */
+// Slew table for 2x drive?
+static const uint32_t slew_2x[] = {
+ 0x00000000, 0x76543210, 0xffffeca8, 0xffffffff,
+ 0x21000000, 0xa8765432, 0xffffffec, 0xffffffff,
+};
+
+// Pull Up / Pull Down offset table, if analogous to IXP2800?
+static const uint32_t pull_updown_offset_table[] = {
+ 0xffffffff, 0xffffffff, 0xffffffff, 0xffffffff,
+ 0x88888888, 0x88888888, 0x88888888, 0x88888888,
+};
+
+/*-----------------------------------------------------------------------------
+Delay functions:
+-----------------------------------------------------------------------------*/
+
+/* Estimate that SLOW_DOWN_IO takes about 1 us */
+#define SLOW_DOWN_IO inb(0x80)
+static void local_udelay(int i)
+{
+ while (i--) {
+ SLOW_DOWN_IO;
+ }
+}
+
+/* delay for 200us */
+#define DO_DELAY local_udelay(200)
+#define EXTRA_DELAY DO_DELAY
+
+/*-----------------------------------------------------------------------------
+Handle (undocumented) control bits MCHTST and PCI_DEV(0,6,0)
+-----------------------------------------------------------------------------*/
+typedef enum {
+ MCHTST_CMD_0,
+ D060_ENABLE,
+ D060_DISABLE,
+ RCOMP_BAR_ENABLE,
+ RCOMP_BAR_DISABLE,
+} mchtst_cc;
+
+typedef enum {
+ D060_CMD_0,
+ D060_CMD_1,
+} d060_cc;
+
+typedef enum {
+ RCOMP_HOLD,
+ RCOMP_RELEASE,
+ RCOMP_SMR_00,
+ RCOMP_SMR_01,
+} rcomp_smr_cc;
+
+/**
+ * MCHTST - 0xF4 - 0xF7 -- Based on similarity to 855PM
+ *
+ * [31:31] Purpose unknown
+ * [30:30] Purpose unknown
+ * [29:23] Unknown - not used?
+ * [22:22] System Memory MMR Enable
+ * 0 == Disable: mem space and BAR at 0x14 are not accessible
+ * 1 == Enable: mem space and BAR at 0x14 are accessible
+ * [21:20] Purpose unknown
+ * [19:02] Unknown - not used?
+ * [01:01] D6EN (Device #6 enable)
+ * 0 == Disable
+ * 1 == Enable
+ * [00:00] Unknown - not used?
+ */
+static void mchtest_control(mchtst_cc cmd)
+{
+ uint32_t dword = pci_read_config32(MCHDEV, MCHTST);
+ switch (cmd) {
+ case MCHTST_CMD_0:
+ dword &= ~(3 << 30);
+ break;
+ case RCOMP_BAR_ENABLE:
+ dword |= (1 << 22);
+ break;
+ case RCOMP_BAR_DISABLE:
+ dword &= ~(1 << 22);
+ break;
+ case D060_ENABLE:
+ dword |= (1 << 1);
+ break;
+ case D060_DISABLE:
+ dword &= ~(1 << 1);
+ break;
+ };
+ pci_write_config32(MCHDEV, MCHTST, dword);
+}
+
+/**
+ *
+ */
+static void d060_control(d060_cc cmd)
+{
+ mchtest_control(D060_ENABLE);
+ uint32_t dword = pci_read_config32(D060DEV, 0xf0);
+ switch (cmd) {
+ case D060_CMD_0:
+ dword |= (1 << 2);
+ break;
+ case D060_CMD_1:
+ dword |= (3 << 27);
+ break;
+ }
+ pci_write_config32(D060DEV, 0xf0, dword);
+ mchtest_control(D060_DISABLE);
+}
+
+/**
+ *
+ */
+static void rcomp_smr_control(rcomp_smr_cc cmd)
+{
+ uint32_t dword = read32(RCOMP_MMIO + SMRCTL);
+ switch (cmd) {
+ case RCOMP_HOLD:
+ dword |= (1 << 9);
+ break;
+ case RCOMP_RELEASE:
+ dword &= ~((1 << 9) | (3 << 0));
+ dword |= (1 << 10) | (1 << 0);
+ break;
+ case RCOMP_SMR_00:
+ dword &= ~(1 << 8);
+ break;
+ case RCOMP_SMR_01:
+ dword |= (1 << 10) | (1 << 8);
+ break;
+ }
+ write32(RCOMP_MMIO + SMRCTL, dword);
+}
+
+/*-----------------------------------------------------------------------------
+Serial presence detect (SPD) functions:
+-----------------------------------------------------------------------------*/
+
+static void die_on_spd_error(int spd_return_value)
+{
+ if (spd_return_value < 0)
+ die("Error reading SPD info\n");
+}
+
+/**
+ * Calculate the page size for each physical bank of the DIMM:
+ * log2(page size) = (# columns) + log2(data width)
+ *
+ * NOTE: Page size is the total number of data bits in a row.
+ *
+ * @param dimm_socket_address SMBus address of DIMM socket to interrogate.
+ * @return log2(page size) for each side of the DIMM.
+ */
+static struct dimm_size sdram_spd_get_page_size(uint16_t dimm_socket_address)
+{
+ uint16_t module_data_width;
+ int value;
+ struct dimm_size pgsz;
+
+ pgsz.side1 = 0;
+ pgsz.side2 = 0;
+
+ // Side 1
+ value = smbus_read_byte(dimm_socket_address, SPD_NUM_COLUMNS);
+ if (value < 0)
+ goto hw_err;
+ pgsz.side1 = value & 0xf; // # columns in bank 1
+
+ /* Get the module data width and convert it to a power of two */
+ value = smbus_read_byte(dimm_socket_address, SPD_MODULE_DATA_WIDTH_MSB);
+ if (value < 0)
+ goto hw_err;
+ module_data_width = (value & 0xff) << 8;
+
+ value = smbus_read_byte(dimm_socket_address, SPD_MODULE_DATA_WIDTH_LSB);
+ if (value < 0)
+ goto hw_err;
+ module_data_width |= (value & 0xff);
+
+ pgsz.side1 += log2(module_data_width);
+
+ /* side two */
+ value = smbus_read_byte(dimm_socket_address, SPD_NUM_DIMM_BANKS);
+ if (value < 0)
+ goto hw_err;
+ if (value > 2)
+ die("Bad SPD value\n");
+ if (value == 2) {
+
+ pgsz.side2 = pgsz.side1; // Assume symmetric banks until we know differently
+ value = smbus_read_byte(dimm_socket_address, SPD_NUM_COLUMNS);
+ if (value < 0)
+ goto hw_err;
+ if ((value & 0xf0) != 0) {
+ // Asymmetric banks
+ pgsz.side2 -= value & 0xf; /* Subtract out columns on side 1 */
+ pgsz.side2 += (value >> 4) & 0xf; /* Add in columns on side 2 */
+ }
+ }
+
+ return pgsz;
+
+hw_err:
+ die(SPD_ERROR);
+ return pgsz; // Never reached
+}
+
+/**
+ * Read the width in bits of each DIMM side's DRAMs via SPD (i.e. 4, 8, 16).
+ *
+ * @param dimm_socket_address SMBus address of DIMM socket to interrogate.
+ * @return Width in bits of each DIMM side's DRAMs.
+ */
+static struct dimm_size sdram_spd_get_width(uint16_t dimm_socket_address)
+{
+ int value;
+ struct dimm_size width;
+
+ width.side1 = 0;
+ width.side2 = 0;
+
+ value = smbus_read_byte(dimm_socket_address, SPD_PRIMARY_SDRAM_WIDTH);
+ die_on_spd_error(value);
+
+ width.side1 = value & 0x7f; // Mask off bank 2 flag
+
+ if (value & 0x80) {
+ width.side2 = width.side1 << 1; // Bank 2 exists and is double-width
+ } else {
+ // If bank 2 exists, it's the same width as bank 1
+ value = smbus_read_byte(dimm_socket_address, SPD_NUM_DIMM_BANKS);
+ die_on_spd_error(value);
+
+ if (value == 2)
+ width.side2 = width.side1;
+ }
+
+ return width;
+}
+
+/**
+ * Calculate the log base 2 size in bits of both DIMM sides.
+ *
+ * log2(# bits) = (# columns) + log2(data width) +
+ * (# rows) + log2(banks per SDRAM)
+ *
+ * Note that it might be easier to use SPD byte 31 here, it has the DIMM size
+ * as a multiple of 4MB. The way we do it now we can size both sides of an
+ * asymmetric DIMM.
+ *
+ * @param dimm_socket_address SMBus address of DIMM socket to interrogate.
+ * @return log2(number of bits) for each side of the DIMM.
+ */
+static struct dimm_size spd_get_dimm_size(unsigned int dimm_socket_address)
+{
+ int value;
+
+ // Start with log2(page size)
+ struct dimm_size sz = sdram_spd_get_page_size(dimm_socket_address);
+
+ if (sz.side1 > 0) {
+
+ value = smbus_read_byte(dimm_socket_address, SPD_NUM_ROWS);
+ die_on_spd_error(value);
+
+ sz.side1 += value & 0xf;
+
+ if (sz.side2 > 0) {
+
+ // Double-sided DIMM
+ if (value & 0xF0)
+ sz.side2 += value >> 4; // Asymmetric
+ else
+ sz.side2 += value; // Symmetric
+ }
+
+ value = smbus_read_byte(dimm_socket_address,
+ SPD_NUM_BANKS_PER_SDRAM);
+ die_on_spd_error(value);
+
+ value = log2(value);
+ sz.side1 += value;
+ if (sz.side2 > 0)
+ sz.side2 += value;
+ }
+
+ return sz;
+}
+
+/**
+ * Determine whether two DIMMs have the same value for an SPD parameter.
+ *
+ * @param spd_byte_number The SPD byte number to compare in both DIMMs.
+ * @param dimm0_address SMBus address of the 1st DIMM socket to interrogate.
+ * @param dimm1_address SMBus address of the 2nd DIMM socket to interrogate.
+ * @return 1 if both DIMM sockets report the same value for the specified
+ * SPD parameter, 0 if the values differed or an error occurred.
+ */
+static uint8_t are_spd_values_equal(uint8_t spd_byte_number,
+ uint16_t dimm0_address,
+ uint16_t dimm1_address)
+{
+ uint8_t bEqual = 0;
+ int dimm0_value = smbus_read_byte(dimm0_address, spd_byte_number);
+ int dimm1_value = smbus_read_byte(dimm1_address, spd_byte_number);
+
+ if ((dimm0_value >= 0) && (dimm1_value >= 0)
+ && (dimm0_value == dimm1_value))
+ bEqual = 1;
+
+ return bEqual;
+}
+
+/**
+ * Scan for compatible DIMMs.
+ *
+ * The code in this module only supports dual-channel operation, so we test
+ * that compatible DIMMs are paired.
+ *
+ * @param ctrl PCI addresses of memory controller functions, and SMBus
+ * addresses of DIMM slots on the mainboard.
+ * @return A bitmask indicating which of the possible sockets for each channel
+ * was found to contain a compatible DIMM.
+ * Bit 0 corresponds to the closest socket for channel 0
+ * Bit 1 to the next socket for channel 0
+ * ...
+ * Bit MAX_DIMM_SOCKETS_PER_CHANNEL-1 to the last socket for channel 0
+ * Bit MAX_DIMM_SOCKETS_PER_CHANNEL is the closest socket for channel 1
+ * ...
+ * Bit 2*MAX_DIMM_SOCKETS_PER_CHANNEL-1 is the last socket for channel 1
+ */
+static uint8_t spd_get_supported_dimms(const struct mem_controller *ctrl)
+{
+ int i;
+ uint8_t dimm_mask = 0;
+
+ // Have to increase size of dimm_mask if this assertion is violated
+ ASSERT(MAX_DIMM_SOCKETS_PER_CHANNEL <= 4);
+
+ // Find DIMMs we can support on channel 0.
+ // Then see if the corresponding channel 1 DIMM has the same parameters,
+ // since we only support dual-channel.
+
+ for (i = 0; i < MAX_DIMM_SOCKETS_PER_CHANNEL; i++) {
+
+ uint16_t channel0_dimm = ctrl->channel0[i];
+ uint16_t channel1_dimm = ctrl->channel1[i];
+ uint8_t bDualChannel = 1;
+ struct dimm_size page_size;
+ struct dimm_size sdram_width;
+ int spd_value;
+
+ if (channel0_dimm == 0)
+ continue; // No such socket on this mainboard
+
+ if (smbus_read_byte(channel0_dimm, SPD_MEMORY_TYPE) !=
+ SPD_MEMORY_TYPE_SDRAM_DDR)
+ continue;
+
+ if (smbus_read_byte(channel0_dimm, SPD_MODULE_VOLTAGE) !=
+ SPD_VOLTAGE_SSTL2)
+ continue; // Unsupported voltage
+
+ // E7501 does not support unregistered DIMMs
+ spd_value = smbus_read_byte(channel0_dimm, SPD_MODULE_ATTRIBUTES);
+ if (!(spd_value & MODULE_REGISTERED) || (spd_value < 0))
+ continue;
+
+ // Must support burst = 4 for dual-channel operation on E7501
+ // NOTE: for single-channel, burst = 8 is required
+ spd_value = smbus_read_byte(channel0_dimm,
+ SPD_SUPPORTED_BURST_LENGTHS);
+ if (!(spd_value & SPD_BURST_LENGTH_4) || (spd_value < 0))
+ continue;
+
+ page_size = sdram_spd_get_page_size(channel0_dimm);
+ sdram_width = sdram_spd_get_width(channel0_dimm);
+
+ // Validate DIMM page size
+ // The E7501 only supports page sizes of 4, 8, 16, or 32 KB per channel
+ // NOTE: 4 KB = 32 Kb = 2^15
+ // 32 KB = 262 Kb = 2^18
+
+ if ((page_size.side1 < 15) || (page_size.side1 > 18))
+ continue;
+
+ // If DIMM is double-sided, verify side2 page size
+ if (page_size.side2 != 0) {
+ if ((page_size.side2 < 15)
+ || (page_size.side2 > 18))
+ continue;
+ }
+ // Validate SDRAM width
+ // The E7501 only supports x4 and x8 devices
+
+ if ((sdram_width.side1 != 4) && (sdram_width.side1 != 8))
+ continue;
+
+ // If DIMM is double-sided, verify side2 width
+ if (sdram_width.side2 != 0) {
+ if ((sdram_width.side2 != 4)
+ && (sdram_width.side2 != 8))
+ continue;
+ }
+
+ // Channel 0 DIMM looks compatible.
+ // Now see if it is paired with the proper DIMM on channel 1.
+
+ ASSERT(channel1_dimm != 0); // No such socket on this mainboard??
+
+ // NOTE: unpopulated DIMMs cause read to fail
+ spd_value = smbus_read_byte(channel1_dimm, SPD_MODULE_ATTRIBUTES);
+ if (!(spd_value & MODULE_REGISTERED) || (spd_value < 0)) {
+
+ printk(BIOS_DEBUG, "Skipping un-matched DIMMs - only dual-channel operation supported\n");
+ continue;
+ }
+
+ spd_value = smbus_read_byte(channel1_dimm,
+ SPD_SUPPORTED_BURST_LENGTHS);
+ if (!(spd_value & SPD_BURST_LENGTH_4) || (spd_value < 0))
+ continue;
+
+ int j;
+ for (j = 0; j < sizeof(dual_channel_parameters); ++j) {
+ if (!are_spd_values_equal
+ (dual_channel_parameters[j], channel0_dimm,
+ channel1_dimm)) {
+
+ bDualChannel = 0;
+ break;
+ }
+ }
+
+ if (bDualChannel) {
+ // This DIMM pair is usable
+ dimm_mask |= 1 << i;
+ dimm_mask |= 1 << (MAX_DIMM_SOCKETS_PER_CHANNEL + i);
+ } else
+ printk(BIOS_DEBUG, "Skipping un-matched DIMMs - only dual-channel operation supported\n");
+ }
+
+ return dimm_mask;
+}
+
+/*-----------------------------------------------------------------------------
+SDRAM configuration functions:
+-----------------------------------------------------------------------------*/
+
+/**
+ * Send the specified command to all DIMMs.
+ *
+ * @param command Specifies the command to be sent to the DIMMs.
+ * @param jedec_mode_bits For the MRS & EMRS commands, bits 0-12 contain the
+ * register value in JEDEC format.
+ */
+static void do_ram_command(uint8_t command, uint16_t jedec_mode_bits)
+{
+ uint8_t dimm_start_64M_multiple;
+ uintptr_t dimm_start_address;
+ uint32_t dram_controller_mode;
+ uint8_t i;
+
+ // Configure the RAM command
+ dram_controller_mode = pci_read_config32(MCHDEV, DRC);
+ dram_controller_mode &= 0xFFFFFF8F;
+ dram_controller_mode |= command;
+ pci_write_config32(MCHDEV, DRC, dram_controller_mode);
+
+ // RAM_COMMAND_NORMAL is an exception.
+ // It affects only the memory controller and does not need to be "sent" to the DIMMs.
+ if (command == RAM_COMMAND_NORMAL) {
+ EXTRA_DELAY;
+ return;
+ }
+
+ // NOTE: for mode select commands, some of the location address bits are part of the command
+ // Map JEDEC mode bits to E7505
+ if (command == RAM_COMMAND_MRS) {
+ // Host address lines [25:18] map to DIMM address lines [7:0]
+ // Host address lines [17:16] map to DIMM address lines [9:8]
+ // Host address lines [15:4] map to DIMM address lines [11:0]
+ dimm_start_address = (jedec_mode_bits & 0x00ff) << 18;
+ dimm_start_address |= (jedec_mode_bits & 0x0300) << 8;
+ dimm_start_address |= (jedec_mode_bits & 0x0fff) << 4;
+ } else if (command == RAM_COMMAND_EMRS) {
+ // Host address lines [15:4] map to DIMM address lines [11:0]
+ dimm_start_address = (jedec_mode_bits << 4);
+ } else {
+ ASSERT(jedec_mode_bits == 0);
+ dimm_start_address = 0;
+ }
+
+ // Send the command to all DIMMs by accessing a memory location within each
+
+ dimm_start_64M_multiple = 0;
+
+ /* FIXME: Only address the number of rows present in the system?
+ * Seems like rows 4-7 overlap with 0-3.
+ */
+ for (i = 0; i < (MAX_NUM_CHANNELS * MAX_DIMM_SOCKETS_PER_CHANNEL); ++i) {
+
+ uint8_t dimm_end_64M_multiple = pci_read_config8(MCHDEV, DRB_ROW_0 + i);
+
+ if (dimm_end_64M_multiple > dimm_start_64M_multiple) {
+ dimm_start_address &= 0x3ffffff;
+ dimm_start_address |= dimm_start_64M_multiple << 26;
+ read32((void *)dimm_start_address);
+ // Set the start of the next DIMM
+ dimm_start_64M_multiple = dimm_end_64M_multiple;
+ }
+ }
+ EXTRA_DELAY;
+}
+
+/**
+ * Set the mode register of all DIMMs.
+ *
+ * The proper CAS# latency setting is added to the mode bits specified
+ * by the caller.
+ *
+ * @param jedec_mode_bits For the MRS & EMRS commands, bits 0-12 contain the
+ * register value in JEDEC format.
+ */
+static void set_ram_mode(uint16_t jedec_mode_bits)
+{
+ ASSERT(!(jedec_mode_bits & SDRAM_CAS_MASK));
+
+ uint32_t dram_cas_latency =
+ pci_read_config32(MCHDEV, DRT) & DRT_CAS_MASK;
+
+ switch (dram_cas_latency) {
+ case DRT_CAS_2_5:
+ jedec_mode_bits |= SDRAM_CAS_2_5;
+ break;
+
+ case DRT_CAS_2_0:
+ jedec_mode_bits |= SDRAM_CAS_2_0;
+ break;
+
+ default:
+ BUG();
+ break;
+ }
+
+ do_ram_command(RAM_COMMAND_MRS, jedec_mode_bits);
+}
+
+/*-----------------------------------------------------------------------------
+DIMM-independent configuration functions:
+-----------------------------------------------------------------------------*/
+
+/**
+ * Configure the E7501's DRAM Row Boundary (DRB) registers for the memory
+ * present in the specified DIMM.
+ *
+ * @param dimm_log2_num_bits Specifies log2(number of bits) for each side of
+ * the DIMM.
+ * @param total_dram_64M_multiple Total DRAM in the system (as a multiple of
+ * 64 MB) for DIMMs < dimm_index.
+ * @param dimm_index Which DIMM pair is being processed
+ * (0..MAX_DIMM_SOCKETS_PER_CHANNEL).
+ * @return New multiple of 64 MB total DRAM in the system.
+ */
+static uint8_t configure_dimm_row_boundaries(struct dimm_size dimm_log2_num_bits, uint8_t total_dram_64M_multiple, unsigned int dimm_index)
+{
+ int i;
+
+ ASSERT(dimm_index < MAX_DIMM_SOCKETS_PER_CHANNEL);
+
+ // DIMM sides must be at least 32 MB
+ ASSERT(dimm_log2_num_bits.side1 >= 28);
+ ASSERT((dimm_log2_num_bits.side2 == 0)
+ || (dimm_log2_num_bits.side2 >= 28));
+
+ // In dual-channel mode, we are called only once for each pair of DIMMs.
+ // Each time we process twice the capacity of a single DIMM.
+
+ // Convert single DIMM capacity to paired DIMM capacity
+ // (multiply by two ==> add 1 to log2)
+ dimm_log2_num_bits.side1++;
+ if (dimm_log2_num_bits.side2 > 0)
+ dimm_log2_num_bits.side2++;
+
+ // Add the capacity of side 1 this DIMM pair (as a multiple of 64 MB)
+ // to the total capacity of the system
+ // NOTE: 64 MB == 512 Mb, and log2(512 Mb) == 29
+
+ total_dram_64M_multiple += (1 << (dimm_log2_num_bits.side1 - 29));
+
+ // Configure the boundary address for the row on side 1
+ pci_write_config8(MCHDEV, DRB_ROW_0 + (dimm_index << 1),
+ total_dram_64M_multiple);
+
+ // If the DIMMs are double-sided, add the capacity of side 2 this DIMM pair
+ // (as a multiple of 64 MB) to the total capacity of the system
+ if (dimm_log2_num_bits.side2 >= 29)
+ total_dram_64M_multiple +=
+ (1 << (dimm_log2_num_bits.side2 - 29));
+
+ // Configure the boundary address for the row (if any) on side 2
+ pci_write_config8(MCHDEV, DRB_ROW_1 + (dimm_index << 1),
+ total_dram_64M_multiple);
+
+ // Update boundaries for rows subsequent to these.
+ // These settings will be overridden by a subsequent call if a populated physical slot exists
+
+ for (i = dimm_index + 1; i < MAX_DIMM_SOCKETS_PER_CHANNEL; i++) {
+ pci_write_config8(MCHDEV, DRB_ROW_0 + (i << 1),
+ total_dram_64M_multiple);
+ pci_write_config8(MCHDEV, DRB_ROW_1 + (i << 1),
+ total_dram_64M_multiple);
+ }
+
+ return total_dram_64M_multiple;
+}
+
+/**
+ * Set the E7501's DRAM row boundary addresses & its Top Of Low Memory (TOLM).
+ *
+ * If necessary, set up a remap window so we don't waste DRAM that ordinarily
+ * would lie behind addresses reserved for memory-mapped I/O.
+ *
+ * @param ctrl PCI addresses of memory controller functions, and SMBus
+ * addresses of DIMM slots on the mainboard.
+ * @param dimm_mask Bitmask of populated DIMMs, see spd_get_supported_dimms().
+ */
+static void configure_e7501_ram_addresses(const struct mem_controller
+ *ctrl, uint8_t dimm_mask)
+{
+ int i;
+ uint8_t total_dram_64M_multiple = 0;
+ uint64_t tolm, tom;
+ uint16_t reg;
+
+ /* FIXME: Is there standard presence detect bit somewhere. */
+ const int agp_slot_disabled = 1;
+
+ /* Start with disabled remap range. */
+ uint16_t remapbase_r = 0x3ff;
+ uint16_t remaplimit_r = 0;
+
+ // Configure the E7501's DRAM row boundaries
+ // Start by zeroing out the temporary initial configuration
+ pci_write_config32(MCHDEV, DRB_ROW_0, 0);
+ pci_write_config32(MCHDEV, DRB_ROW_4, 0);
+
+ for (i = 0; i < MAX_DIMM_SOCKETS_PER_CHANNEL; i++) {
+
+ uint16_t dimm_socket_address = ctrl->channel0[i];
+ struct dimm_size sz;
+
+ if (!(dimm_mask & (1 << i)))
+ continue; // This DIMM not present
+
+ sz = spd_get_dimm_size(dimm_socket_address);
+
+ RAM_DEBUG_MESSAGE("dimm size =");
+ RAM_DEBUG_HEX32((u32)sz.side1);
+ RAM_DEBUG_MESSAGE(" ");
+ RAM_DEBUG_HEX32((u32)sz.side2);
+ RAM_DEBUG_MESSAGE("\n");
+
+ if (sz.side1 == 0)
+ die("Bad SPD value\n");
+
+ total_dram_64M_multiple =
+ configure_dimm_row_boundaries(sz, total_dram_64M_multiple, i);
+ }
+
+ tom = total_dram_64M_multiple * 64ULL * MiB;
+
+ /* Reserve MMIO space. */
+ tolm = 4ULL * GiB - 512 * MiB;
+ if (agp_slot_disabled) {
+ /* Reduce apertures to 2 x 4 MiB. */
+ pci_write_config8(MCHDEV, APSIZE, 0x3F);
+ pci_write_config16(AGPDEV, APSIZE1, 0x3F);
+ } else {
+ /* Add MMIO reserve for 2 x 256 MiB apertures. */
+ tolm -= 512 * MiB;
+ }
+ tolm = MIN(tolm, tom);
+
+ /* The PCI memory hole overlaps memory setup the remap window. */
+ if (tolm < tom) {
+ uint64_t remapbase = MAX(tom, 4ULL * GiB);
+ uint64_t remaplimit = remapbase + (4ULL * GiB - tolm);
+
+ remapbase_r = remapbase / (64 * MiB);
+ remaplimit_r = remaplimit / (64 * MiB);
+
+ /* Limit register is inclusive. */
+ remaplimit_r -= 1;
+ }
+
+ /* Write the RAM configuration registers,
+ preserving the reserved bits. */
+ reg = pci_read_config16(MCHDEV, TOLM) & 0x7ff;
+ reg |= (tolm / (128 * MiB)) << 11;
+ pci_write_config16(MCHDEV, TOLM, reg);
+
+ reg = pci_read_config16(MCHDEV, REMAPBASE) & 0xfc00;
+ reg |= remapbase_r;
+ pci_write_config16(MCHDEV, REMAPBASE, reg);
+
+ reg = pci_read_config16(MCHDEV, REMAPLIMIT) & 0xfc00;
+ reg |= remaplimit_r;
+ pci_write_config16(MCHDEV, REMAPLIMIT, reg);
+}
+
+/**
+ * Program the DRAM Timing register (DRT) of the E7501 (except for CAS#
+ * latency, which is assumed to have been programmed already), based on the
+ * parameters of the various installed DIMMs.
+ *
+ * @param ctrl PCI addresses of memory controller functions, and SMBus
+ * addresses of DIMM slots on the mainboard.
+ * @param dimm_mask Bitmask of populated DIMMs, see spd_get_supported_dimms().
+ */
+static void configure_e7501_dram_timing(const struct mem_controller *ctrl,
+ uint8_t dimm_mask)
+{
+ int i;
+ uint32_t dram_timing;
+ int value;
+ uint8_t slowest_row_precharge = 0;
+ uint8_t slowest_ras_cas_delay = 0;
+ uint8_t slowest_active_to_precharge_delay = 0;
+ uint32_t current_cas_latency =
+ pci_read_config32(MCHDEV, DRT) & DRT_CAS_MASK;
+
+ // CAS# latency must be programmed beforehand
+ ASSERT((current_cas_latency == DRT_CAS_2_0)
+ || (current_cas_latency == DRT_CAS_2_5));
+
+ // Each timing parameter is determined by the slowest DIMM
+
+ for (i = 0; i < MAX_DIMM_SOCKETS; i++) {
+ uint16_t dimm_socket_address;
+
+ if (!(dimm_mask & (1 << i)))
+ continue; // This DIMM not present
+
+ if (i < MAX_DIMM_SOCKETS_PER_CHANNEL)
+ dimm_socket_address = ctrl->channel0[i];
+ else
+ dimm_socket_address =
+ ctrl->channel1[i - MAX_DIMM_SOCKETS_PER_CHANNEL];
+
+ value = smbus_read_byte(dimm_socket_address,
+ SPD_MIN_ROW_PRECHARGE_TIME);
+ if (value < 0)
+ goto hw_err;
+ if (value > slowest_row_precharge)
+ slowest_row_precharge = value;
+
+ value = smbus_read_byte(dimm_socket_address,
+ SPD_MIN_RAS_TO_CAS_DELAY);
+ if (value < 0)
+ goto hw_err;
+ if (value > slowest_ras_cas_delay)
+ slowest_ras_cas_delay = value;
+
+ value = smbus_read_byte(dimm_socket_address,
+ SPD_MIN_ACTIVE_TO_PRECHARGE_DELAY);
+ if (value < 0)
+ goto hw_err;
+ if (value > slowest_active_to_precharge_delay)
+ slowest_active_to_precharge_delay = value;
+ }
+
+ // NOTE for timing parameters:
+ // At 133 MHz, 1 clock == 7.52 ns
+
+ /* Read the initial state */
+ dram_timing = pci_read_config32(MCHDEV, DRT);
+
+ /* Trp */
+
+ // E7501 supports only 2 or 3 clocks for tRP
+ if (slowest_row_precharge > ((22 << 2) | (2 << 0)))
+ die("unsupported DIMM tRP"); // > 22.5 ns: 4 or more clocks
+ else if (slowest_row_precharge > (15 << 2))
+ dram_timing &= ~(1 << 0); // > 15.0 ns: 3 clocks
+ else
+ dram_timing |= (1 << 0); // <= 15.0 ns: 2 clocks
+
+ /* Trcd */
+
+ // E7501 supports only 2 or 3 clocks for tRCD
+ // Use the same value for both read & write
+ dram_timing &= ~((1 << 3) | (3 << 1));
+ if (slowest_ras_cas_delay > ((22 << 2) | (2 << 0)))
+ die("unsupported DIMM tRCD"); // > 22.5 ns: 4 or more clocks
+ else if (slowest_ras_cas_delay > (15 << 2))
+ dram_timing |= (2 << 1); // > 15.0 ns: 3 clocks
+ else
+ dram_timing |= ((1 << 3) | (3 << 1)); // <= 15.0 ns: 2 clocks
+
+ /* Tras */
+
+ // E7501 supports only 5, 6, or 7 clocks for tRAS
+ // 5 clocks ~= 37.6 ns, 6 clocks ~= 45.1 ns, 7 clocks ~= 52.6 ns
+ dram_timing &= ~(3 << 9);
+
+ if (slowest_active_to_precharge_delay > 52)
+ die("unsupported DIMM tRAS"); // > 52 ns: 8 or more clocks
+ else if (slowest_active_to_precharge_delay > 45)
+ dram_timing |= (0 << 9); // 46-52 ns: 7 clocks
+ else if (slowest_active_to_precharge_delay > 37)
+ dram_timing |= (1 << 9); // 38-45 ns: 6 clocks
+ else
+ dram_timing |= (2 << 9); // < 38 ns: 5 clocks
+
+ /* Trd */
+
+ /* Set to a 7 clock read delay. This is for 133MHz
+ * with a CAS latency of 2.5 if 2.0 a 6 clock
+ * delay is good */
+
+ dram_timing &= ~(7 << 24); // 7 clocks
+ if (current_cas_latency == DRT_CAS_2_0)
+ dram_timing |= (1 << 24); // 6 clocks
+
+ /*
+ * Back to Back Read-Write Turn Around
+ */
+ /* Set to a 5 clock back to back read to write turn around.
+ * 4 is a good delay if the CAS latency is 2.0 */
+
+ dram_timing &= ~(1 << 28); // 5 clocks
+ if (current_cas_latency == DRT_CAS_2_0)
+ dram_timing |= (1 << 28); // 4 clocks
+
+ pci_write_config32(MCHDEV, DRT, dram_timing);
+
+ return;
+
+hw_err:
+ die(SPD_ERROR);
+}
+
+/**
+ * Determine the shortest CAS# latency that the E7501 and all DIMMs have in
+ * common, and program the E7501 to use it.
+ *
+ * @param ctrl PCI addresses of memory controller functions, and SMBus
+ * addresses of DIMM slots on the mainboard.
+ * @param dimm_mask Bitmask of populated DIMMs, spd_get_supported_dimms().
+ */
+static void configure_e7501_cas_latency(const struct mem_controller *ctrl,
+ uint8_t dimm_mask)
+{
+ int i;
+ int value;
+ uint32_t dram_timing;
+ uint16_t dram_read_timing;
+ uint32_t dword;
+
+ // CAS# latency bitmasks in SPD_ACCEPTABLE_CAS_LATENCIES format
+ // NOTE: E7501 supports only 2.0 and 2.5
+ uint32_t system_compatible_cas_latencies =
+ SPD_CAS_LATENCY_2_0 | SPD_CAS_LATENCY_2_5;
+ uint32_t current_cas_latency;
+ uint32_t dimm_compatible_cas_latencies;
+
+ for (i = 0; i < MAX_DIMM_SOCKETS; i++) {
+
+ uint16_t dimm_socket_address;
+
+ if (!(dimm_mask & (1 << i)))
+ continue; // This DIMM not usable
+
+ if (i < MAX_DIMM_SOCKETS_PER_CHANNEL)
+ dimm_socket_address = ctrl->channel0[i];
+ else
+ dimm_socket_address =
+ ctrl->channel1[i - MAX_DIMM_SOCKETS_PER_CHANNEL];
+
+ value = smbus_read_byte(dimm_socket_address,
+ SPD_ACCEPTABLE_CAS_LATENCIES);
+ if (value < 0)
+ goto hw_err;
+
+ dimm_compatible_cas_latencies = value & 0x7f; // Start with all supported by DIMM
+ current_cas_latency = 1 << log2(dimm_compatible_cas_latencies); // Max supported by DIMM
+
+ // Can we support the highest CAS# latency?
+
+ value = smbus_read_byte(dimm_socket_address,
+ SPD_MIN_CYCLE_TIME_AT_CAS_MAX);
+ if (value < 0)
+ goto hw_err;
+
+ // NOTE: At 133 MHz, 1 clock == 7.52 ns
+ if (value > 0x75) {
+ // Our bus is too fast for this CAS# latency
+ // Remove it from the bitmask of those supported by the DIMM that are compatible
+ dimm_compatible_cas_latencies &= ~current_cas_latency;
+ }
+ // Can we support the next-highest CAS# latency (max - 0.5)?
+
+ current_cas_latency >>= 1;
+ if (current_cas_latency != 0) {
+ value = smbus_read_byte(dimm_socket_address,
+ SPD_SDRAM_CYCLE_TIME_2ND);
+ if (value < 0)
+ goto hw_err;
+ if (value > 0x75)
+ dimm_compatible_cas_latencies &=
+ ~current_cas_latency;
+ }
+ // Can we support the next-highest CAS# latency (max - 1.0)?
+ current_cas_latency >>= 1;
+ if (current_cas_latency != 0) {
+ value = smbus_read_byte(dimm_socket_address,
+ SPD_SDRAM_CYCLE_TIME_3RD);
+ if (value < 0)
+ goto hw_err;
+ if (value > 0x75)
+ dimm_compatible_cas_latencies &=
+ ~current_cas_latency;
+ }
+ // Restrict the system to CAS# latencies compatible with this DIMM
+ system_compatible_cas_latencies &=
+ dimm_compatible_cas_latencies;
+
+ /* go to the next DIMM */
+ }
+
+ /* After all of the arduous calculation setup with the fastest
+ * cas latency I can use.
+ */
+
+ dram_timing = pci_read_config32(MCHDEV, DRT);
+ dram_timing &= ~(DRT_CAS_MASK);
+
+ dram_read_timing =
+ pci_read_config16(MCHDEV, DRDCTL);
+ dram_read_timing &= 0xF000;
+
+ if (system_compatible_cas_latencies & SPD_CAS_LATENCY_2_0) {
+ dram_timing |= DRT_CAS_2_0;
+ dram_read_timing |= 0x0222;
+ } else if (system_compatible_cas_latencies & SPD_CAS_LATENCY_2_5) {
+
+ uint32_t dram_row_attributes =
+ pci_read_config32(MCHDEV, DRA);
+
+ dram_timing |= DRT_CAS_2_5;
+
+ // At CAS# 2.5, DRAM Read Timing (if that's what it its) appears to need a slightly
+ // different value if all DIMM slots are populated
+
+ if ((dram_row_attributes & 0xff)
+ && (dram_row_attributes & 0xff00)
+ && (dram_row_attributes & 0xff0000)
+ && (dram_row_attributes & 0xff000000)) {
+
+ // All slots populated
+ dram_read_timing |= 0x0882;
+ } else {
+ // Some unpopulated slots
+ dram_read_timing |= 0x0662;
+ }
+ } else
+ die("No CAS# latencies compatible with all DIMMs!!\n");
+
+ pci_write_config32(MCHDEV, DRT, dram_timing);
+
+ /* set master DLL reset */
+ dword = pci_read_config32(MCHDEV, 0x88);
+ dword |= (1 << 26);
+ pci_write_config32(MCHDEV, 0x88, dword);
+ /* patch try register 88 is undocumented tnz */
+ dword &= 0x0ca17fff;
+ dword |= 0xd14a5000;
+ pci_write_config32(MCHDEV, 0x88, dword);
+
+ pci_write_config16(MCHDEV, DRDCTL,
+ dram_read_timing);
+
+ /* clear master DLL reset */
+ dword = pci_read_config32(MCHDEV, 0x88);
+ dword &= ~(1 << 26);
+ pci_write_config32(MCHDEV, 0x88, dword);
+
+ return;
+
+hw_err:
+ die(SPD_ERROR);
+}
+
+/**
+ * Configure the refresh interval so that we refresh no more often than
+ * required by the "most needy" DIMM. Also disable ECC if any of the DIMMs
+ * don't support it.
+ *
+ * @param ctrl PCI addresses of memory controller functions, and SMBus
+ * addresses of DIMM slots on the mainboard.
+ * @param dimm_mask Bitmask of populated DIMMs, spd_get_supported_dimms().
+ */
+static void configure_e7501_dram_controller_mode(const struct mem_controller *ctrl,
+ uint8_t dimm_mask)
+{
+ int i;
+
+ // Initial settings
+ uint32_t controller_mode = pci_read_config32(MCHDEV, DRC);
+ uint32_t system_refresh_mode = (controller_mode >> 8) & 7;
+
+ // Code below assumes that most aggressive settings are in
+ // force when we are called, either via E7501 reset defaults
+ // or by sdram_set_registers():
+ // - ECC enabled
+ // - No refresh
+
+ ASSERT((controller_mode & (3 << 20)) == (2 << 20)); // ECC
+ ASSERT(!(controller_mode & (7 << 8))); // Refresh
+
+ /* Walk through _all_ dimms and find the least-common denominator for:
+ * - ECC support
+ * - refresh rates
+ */
+
+ for (i = 0; i < MAX_DIMM_SOCKETS; i++) {
+
+ uint32_t dimm_refresh_mode;
+ int value;
+ uint16_t dimm_socket_address;
+
+ if (!(dimm_mask & (1 << i))) {
+ continue; // This DIMM not usable
+ }
+
+ if (i < MAX_DIMM_SOCKETS_PER_CHANNEL)
+ dimm_socket_address = ctrl->channel0[i];
+ else
+ dimm_socket_address =
+ ctrl->channel1[i -
+ MAX_DIMM_SOCKETS_PER_CHANNEL];
+
+ // Disable ECC mode if any one of the DIMMs does not support ECC
+ // SJM: Should we just die here? E7501 datasheet says non-ECC DIMMs aren't supported.
+
+ value = smbus_read_byte(dimm_socket_address,
+ SPD_DIMM_CONFIG_TYPE);
+ die_on_spd_error(value);
+ if (value != ERROR_SCHEME_ECC) {
+ controller_mode &= ~(3 << 20);
+ }
+
+ value = smbus_read_byte(dimm_socket_address, SPD_REFRESH);
+ die_on_spd_error(value);
+ value &= 0x7f; // Mask off self-refresh bit
+ if (value > MAX_SPD_REFRESH_RATE) {
+ printk(BIOS_ERR, "unsupported refresh rate\n");
+ continue;
+ }
+ // Get the appropriate E7501 refresh mode for this DIMM
+ dimm_refresh_mode = refresh_rate_map[value];
+ if (dimm_refresh_mode > 7) {
+ printk(BIOS_ERR, "unsupported refresh rate\n");
+ continue;
+ }
+ // If this DIMM requires more frequent refresh than others,
+ // update the system setting
+ if (refresh_frequency[dimm_refresh_mode] >
+ refresh_frequency[system_refresh_mode])
+ system_refresh_mode = dimm_refresh_mode;
+
+ /* go to the next DIMM */
+ }
+
+ controller_mode |= (system_refresh_mode << 8);
+
+ // Configure the E7501
+ pci_write_config32(MCHDEV, DRC, controller_mode);
+}
+
+/**
+ * Configure the E7501's DRAM Row Attributes (DRA) registers based on DIMM
+ * parameters read via SPD. This tells the controller the width of the SDRAM
+ * chips on each DIMM side (x4 or x8) and the page size of each DIMM side
+ * (4, 8, 16, or 32 KB).
+ *
+ * @param ctrl PCI addresses of memory controller functions, and SMBus
+ * addresses of DIMM slots on the mainboard.
+ * @param dimm_mask Bitmask of populated DIMMs, spd_get_supported_dimms().
+ */
+static void configure_e7501_row_attributes(const struct mem_controller
+ *ctrl, uint8_t dimm_mask)
+{
+ int i;
+ uint32_t row_attributes = 0;
+
+ for (i = 0; i < MAX_DIMM_SOCKETS_PER_CHANNEL; i++) {
+
+ uint16_t dimm_socket_address = ctrl->channel0[i];
+ struct dimm_size page_size;
+ struct dimm_size sdram_width;
+
+ if (!(dimm_mask & (1 << i)))
+ continue; // This DIMM not usable
+
+ // Get the relevant parameters via SPD
+ page_size = sdram_spd_get_page_size(dimm_socket_address);
+ sdram_width = sdram_spd_get_width(dimm_socket_address);
+
+ // Update the DRAM Row Attributes.
+ // Page size is encoded as log2(page size in bits) - log2(8 Kb)
+ // NOTE: 8 Kb = 2^13
+ row_attributes |= (page_size.side1 - 13) << (i << 3); // Side 1 of each DIMM is an EVEN row
+
+ if (sdram_width.side2 > 0)
+ row_attributes |= (page_size.side2 - 13) << ((i << 3) + 4); // Side 2 is ODD
+
+ // Set x4 flags if appropriate
+ if (sdram_width.side1 == 4) {
+ row_attributes |= 0x08 << (i << 3);
+ }
+
+ if (sdram_width.side2 == 4) {
+ row_attributes |= 0x08 << ((i << 3) + 4);
+ }
+
+ /* go to the next DIMM */
+ }
+
+ /* Write the new row attributes register */
+ pci_write_config32(MCHDEV, DRA, row_attributes);
+}
+
+/*
+ * Enable clock signals for populated DIMM sockets and disable them for
+ * unpopulated sockets (to reduce EMI).
+ *
+ * @param dimm_mask Bitmask of populated DIMMs, see spd_get_supported_dimms().
+ */
+static void enable_e7501_clocks(uint8_t dimm_mask)
+{
+ int i;
+ uint8_t clock_disable = pci_read_config8(MCHDEV, CKDIS);
+
+ pci_write_config8(MCHDEV, 0x8e, 0xb0);
+
+ for (i = 0; i < MAX_DIMM_SOCKETS_PER_CHANNEL; i++) {
+
+ uint8_t socket_mask = 1 << i;
+
+ if (dimm_mask & socket_mask)
+ clock_disable &= ~socket_mask; // DIMM present, enable clock
+ else
+ clock_disable |= socket_mask; // DIMM absent, disable clock
+ }
+
+ pci_write_config8(MCHDEV, CKDIS, clock_disable);
+}
+
+/* DIMM-dependent configuration functions */
+
+/**
+ * DDR Receive FIFO RE-Sync (?)
+ */
+static void RAM_RESET_DDR_PTR(void)
+{
+ uint8_t byte;
+ byte = pci_read_config8(MCHDEV, 0x88);
+ byte |= (1 << 4);
+ pci_write_config8(MCHDEV, 0x88, byte);
+
+ byte = pci_read_config8(MCHDEV, 0x88);
+ byte &= ~(1 << 4);
+ pci_write_config8(MCHDEV, 0x88, byte);
+}
+
+/**
+ * Copy 64 bytes from one location to another.
+ *
+ * @param src_addr TODO
+ * @param dst_addr TODO
+ */
+static void write_8dwords(const uint32_t *src_addr, u8 *dst_addr)
+{
+ int i;
+ for (i = 0; i < 8; i++) {
+ write32(dst_addr, *src_addr);
+ src_addr++;
+ dst_addr += sizeof(uint32_t);
+ }
+}
+
+/**
+ * Set the E7501's (undocumented) RCOMP registers.
+ *
+ * Per the 855PM datasheet and IXP2800 HW Initialization Reference Manual,
+ * RCOMP registers appear to affect drive strength, pullup/pulldown offset,
+ * and slew rate of various signal groups.
+ *
+ * Comments below are conjecture based on apparent similarity between the
+ * E7501 and these two chips.
+ */
+static void rcomp_copy_registers(void)
+{
+ uint32_t dword;
+ uint8_t strength_control;
+
+ RAM_DEBUG_MESSAGE("Setting RCOMP registers.\n");
+
+ /* Begin to write the RCOMP registers */
+ write8(RCOMP_MMIO + 0x2c, 0x0);
+
+ // Set CMD and DQ/DQS strength to 2x (?)
+ strength_control = read8(RCOMP_MMIO + DQCMDSTR) & 0x88;
+ strength_control |= 0x40;
+ write8(RCOMP_MMIO + DQCMDSTR, strength_control);
+ write_8dwords(slew_2x, RCOMP_MMIO + 0x80);
+ write16(RCOMP_MMIO + 0x42, 0);
+
+ // Set CMD and DQ/DQS strength to 2x (?)
+ strength_control = read8(RCOMP_MMIO + DQCMDSTR) & 0xF8;
+ strength_control |= 0x04;
+ write8(RCOMP_MMIO + DQCMDSTR, strength_control);
+ write_8dwords(slew_2x, RCOMP_MMIO + 0x60);
+ write16(RCOMP_MMIO + 0x40, 0);
+
+ // Set RCVEnOut# strength to 2x (?)
+ strength_control = read8(RCOMP_MMIO + RCVENSTR) & 0xF8;
+ strength_control |= 0x04;
+ write8(RCOMP_MMIO + RCVENSTR, strength_control);
+ write_8dwords(slew_2x, RCOMP_MMIO + 0x1c0);
+ write16(RCOMP_MMIO + 0x50, 0);
+
+ // Set CS# strength for x4 SDRAM to 2x (?)
+ strength_control = read8(RCOMP_MMIO + CSBSTR) & 0x88;
+ strength_control |= 0x04;
+ write8(RCOMP_MMIO + CSBSTR, strength_control);
+ write_8dwords(slew_2x, RCOMP_MMIO + 0x140);
+ write16(RCOMP_MMIO + 0x48, 0);
+
+ // Set CS# strength for x4 SDRAM to 2x (?)
+ strength_control = read8(RCOMP_MMIO + CSBSTR) & 0x8F;
+ strength_control |= 0x40;
+ write8(RCOMP_MMIO + CSBSTR, strength_control);
+ write_8dwords(slew_2x, RCOMP_MMIO + 0x160);
+ write16(RCOMP_MMIO + 0x4a, 0);
+
+ // Set CKE strength for x4 SDRAM to 2x (?)
+ strength_control = read8(RCOMP_MMIO + CKESTR) & 0x88;
+ strength_control |= 0x04;
+ write8(RCOMP_MMIO + CKESTR, strength_control);
+ write_8dwords(slew_2x, RCOMP_MMIO + 0xa0);
+ write16(RCOMP_MMIO + 0x44, 0);
+
+ // Set CKE strength for x4 SDRAM to 2x (?)
+ strength_control = read8(RCOMP_MMIO + CKESTR) & 0x8F;
+ strength_control |= 0x40;
+ write8(RCOMP_MMIO + CKESTR, strength_control);
+ write_8dwords(slew_2x, RCOMP_MMIO + 0xc0);
+ write16(RCOMP_MMIO + 0x46, 0);
+
+ // Set CK strength for x4 SDRAM to 1x (?)
+ strength_control = read8(RCOMP_MMIO + CKSTR) & 0x88;
+ strength_control |= 0x01;
+ write8(RCOMP_MMIO + CKSTR, strength_control);
+ write_8dwords(pull_updown_offset_table, RCOMP_MMIO + 0x180);
+ write16(RCOMP_MMIO + 0x4c, 0);
+
+ // Set CK strength for x4 SDRAM to 1x (?)
+ strength_control = read8(RCOMP_MMIO + CKSTR) & 0x8F;
+ strength_control |= 0x10;
+ write8(RCOMP_MMIO + CKSTR, strength_control);
+ write_8dwords(pull_updown_offset_table, RCOMP_MMIO + 0x1a0);
+ write16(RCOMP_MMIO + 0x4e, 0);
+
+ dword = read32(RCOMP_MMIO + 0x400);
+ dword &= 0x7f7fffff;
+ write32(RCOMP_MMIO + 0x400, dword);
+
+ dword = read32(RCOMP_MMIO + 0x408);
+ dword &= 0x7f7fffff;
+ write32(RCOMP_MMIO + 0x408, dword);
+}
+
+static void ram_set_rcomp_regs(void)
+{
+ /* Set the RCOMP MMIO base address */
+ mchtest_control(RCOMP_BAR_ENABLE);
+ pci_write_config32(MCHDEV, SMRBASE, (uintptr_t)RCOMP_MMIO);
+
+ /* Block RCOMP updates while we configure the registers */
+ rcomp_smr_control(RCOMP_HOLD);
+ rcomp_copy_registers();
+ d060_control(D060_CMD_0);
+ mchtest_control(MCHTST_CMD_0);
+
+ uint8_t revision = pci_read_config8(MCHDEV, 0x08);
+ if (revision >= 3) {
+ rcomp_smr_control(RCOMP_SMR_00);
+ rcomp_smr_control(RCOMP_SMR_01);
+ }
+ rcomp_smr_control(RCOMP_RELEASE);
+
+ /* Wait 40 usec */
+ SLOW_DOWN_IO;
+
+ /* Clear the RCOMP MMIO base address */
+ pci_write_config32(MCHDEV, SMRBASE, 0);
+ mchtest_control(RCOMP_BAR_DISABLE);
+}
+
+/*-----------------------------------------------------------------------------
+Public interface:
+-----------------------------------------------------------------------------*/
+
+/**
+ * Go through the JEDEC initialization sequence for all DIMMs, then enable
+ * refresh and initialize ECC and memory to zero. Upon exit, SDRAM is up
+ * and running.
+ *
+ * @param ctrl PCI addresses of memory controller functions, and SMBus
+ * addresses of DIMM slots on the mainboard.
+ */
+static void sdram_enable(const struct mem_controller *ctrl)
+{
+ uint8_t dimm_mask = pci_read_config16(MCHDEV, SKPD);
+ uint32_t dram_controller_mode;
+
+ if (dimm_mask == 0)
+ return;
+
+ /* 1 & 2 Power up and start clocks */
+ RAM_DEBUG_MESSAGE("Ram Enable 1\n");
+ RAM_DEBUG_MESSAGE("Ram Enable 2\n");
+
+ /* A 200us delay is needed */
+ DO_DELAY; EXTRA_DELAY;
+
+ /* 3. Apply NOP */
+ RAM_DEBUG_MESSAGE("Ram Enable 3\n");
+ do_ram_command(RAM_COMMAND_NOP, 0);
+
+ /* 4 Precharge all */
+ RAM_DEBUG_MESSAGE("Ram Enable 4\n");
+ do_ram_command(RAM_COMMAND_PRECHARGE, 0);
+ /* wait until the all banks idle state... */
+
+ /* 5. Issue EMRS to enable DLL */
+ RAM_DEBUG_MESSAGE("Ram Enable 5\n");
+ do_ram_command(RAM_COMMAND_EMRS,
+ SDRAM_EXTMODE_DLL_ENABLE |
+ SDRAM_EXTMODE_DRIVE_NORMAL);
+
+ /* 6. Reset DLL */
+ RAM_DEBUG_MESSAGE("Ram Enable 6\n");
+ set_ram_mode(E7501_SDRAM_MODE | SDRAM_MODE_DLL_RESET);
+ EXTRA_DELAY;
+ /* Ensure a 200us delay between the DLL reset in step 6 and the final
+ * mode register set in step 9.
+ * Infineon needs this before any other command is sent to the ram.
+ */
+ DO_DELAY; EXTRA_DELAY;
+
+ /* 7 Precharge all */
+ RAM_DEBUG_MESSAGE("Ram Enable 7\n");
+ do_ram_command(RAM_COMMAND_PRECHARGE, 0);
+
+ /* 8 Now we need 2 AUTO REFRESH / CBR cycles to be performed */
+ /* And for good luck 6 more CBRs */
+ RAM_DEBUG_MESSAGE("Ram Enable 8\n");
+ int i;
+ for (i = 0; i < 8; i++)
+ do_ram_command(RAM_COMMAND_CBR, 0);
+
+ /* 9 mode register set */
+ RAM_DEBUG_MESSAGE("Ram Enable 9\n");
+ set_ram_mode(E7501_SDRAM_MODE | SDRAM_MODE_NORMAL);
+
+ /* 10 DDR Receive FIFO RE-Sync */
+ RAM_DEBUG_MESSAGE("Ram Enable 10\n");
+ RAM_RESET_DDR_PTR();
+ EXTRA_DELAY;
+
+ /* 11 normal operation */
+ RAM_DEBUG_MESSAGE("Ram Enable 11\n");
+ do_ram_command(RAM_COMMAND_NORMAL, 0);
+
+ // Reconfigure the row boundaries and Top of Low Memory
+ // to match the true size of the DIMMs
+ configure_e7501_ram_addresses(ctrl, dimm_mask);
+
+ /* Finally enable refresh */
+ dram_controller_mode = pci_read_config32(MCHDEV, DRC);
+ dram_controller_mode |= (1 << 29);
+ pci_write_config32(MCHDEV, DRC, dram_controller_mode);
+ EXTRA_DELAY;
+}
+
+/**
+ * @param ctrl PCI addresses of memory controller functions, and SMBus
+ * addresses of DIMM slots on the mainboard.
+ */
+static void sdram_post_ecc(const struct mem_controller *ctrl)
+{
+ /* Fast CS# Enable. */
+ uint32_t dram_controller_mode = pci_read_config32(MCHDEV, DRC);
+ dram_controller_mode = pci_read_config32(MCHDEV, DRC);
+ dram_controller_mode |= (1 << 17);
+ pci_write_config32(MCHDEV, DRC, dram_controller_mode);
+}
+
+/**
+ * Configure SDRAM controller parameters that depend on characteristics of the
+ * DIMMs installed in the system. These characteristics are read from the
+ * DIMMs via the standard Serial Presence Detect (SPD) interface.
+ *
+ * @param ctrl PCI addresses of memory controller functions, and SMBus
+ * addresses of DIMM slots on the mainboard.
+ */
+static void sdram_set_spd_registers(const struct mem_controller *ctrl)
+{
+ uint8_t dimm_mask;
+
+ RAM_DEBUG_MESSAGE("Reading SPD data...\n");
+
+ dimm_mask = spd_get_supported_dimms(ctrl);
+
+ if (dimm_mask == 0) {
+ printk(BIOS_DEBUG, "No usable memory for this controller\n");
+ } else {
+ enable_e7501_clocks(dimm_mask);
+
+ RAM_DEBUG_MESSAGE("setting based on SPD data...\n");
+
+ configure_e7501_row_attributes(ctrl, dimm_mask);
+ configure_e7501_dram_controller_mode(ctrl, dimm_mask);
+ configure_e7501_cas_latency(ctrl, dimm_mask);
+ RAM_RESET_DDR_PTR();
+
+ configure_e7501_dram_timing(ctrl, dimm_mask);
+ DO_DELAY;
+ RAM_DEBUG_MESSAGE("done\n");
+ }
+
+ /* NOTE: configure_e7501_ram_addresses() is NOT called here.
+ * We want to keep the default 64 MB/row mapping until sdram_enable() is called,
+ * even though the default mapping is almost certainly incorrect.
+ * The default mapping makes it easy to initialize all of the DIMMs
+ * even if the total system memory is > 4 GB.
+ *
+ * Save the dimm_mask for when sdram_enable is called, so it can call
+ * configure_e7501_ram_addresses() without having to regenerate the bitmask
+ * of usable DIMMs.
+ */
+ pci_write_config16(MCHDEV, SKPD, dimm_mask);
+}
+
+/**
+ * Do basic RAM setup that does NOT depend on serial presence detect
+ * information (i.e. independent of DIMM specifics).
+ *
+ * @param ctrl PCI addresses of memory controller functions, and SMBus
+ * addresses of DIMM slots on the mainboard.
+ */
+static void sdram_set_registers(const struct mem_controller *ctrl)
+{
+ uint32_t dword;
+ uint16_t word;
+ uint8_t byte;
+
+ ram_set_rcomp_regs();
+
+ /* Enable 0:0.1, 0:2.1 */
+ word = pci_read_config16(MCHDEV, DVNP);
+ word &= ~0x05;
+ pci_write_config16(MCHDEV, DVNP, word);
+
+ /* Disable high-memory remap (power-on defaults, really) */
+ pci_write_config16(MCHDEV, REMAPBASE, 0x03ff);
+ pci_write_config16(MCHDEV, REMAPLIMIT, 0x0);
+
+ /* Disable legacy MMIO (0xC0000-0xEFFFF is DRAM) */
+ int i;
+ pci_write_config8(MCHDEV, PAM_0, 0x30);
+ for (i = 1; i <= 6; i++)
+ pci_write_config8(MCHDEV, PAM_0 + i, 0x33);
+
+ /* Conservatively say each row has 64MB of ram, we will fix this up later
+ * Initial TOLM 8 rows 64MB each (1<<3 * 1<<26) >> 16 = 1<<13
+ *
+ * FIXME: Hard-coded limit to first four rows to prevent overlap!
+ */
+ pci_write_config32(MCHDEV, DRB_ROW_0, 0x04030201);
+ pci_write_config32(MCHDEV, DRB_ROW_4, 0x04040404);
+ //pci_write_config32(MCHDEV, DRB_ROW_4, 0x08070605);
+ pci_write_config16(MCHDEV, TOLM, (1<<13));
+
+ /* DIMM clocks off */
+ pci_write_config8(MCHDEV, CKDIS, 0xff);
+
+ /* reset row attributes */
+ pci_write_config32(MCHDEV, DRA, 0x0);
+
+ // The only things we need to set here are DRAM idle timer, Back-to-Back Read Turnaround, and
+ // Back-to-Back Write-Read Turnaround. All others are configured based on SPD.
+ dword = pci_read_config32(MCHDEV, DRT);
+ dword &= 0xC7F8FFFF;
+ dword |= (0x28<<24)|(0x03<<16);
+ pci_write_config32(MCHDEV, DRT, dword);
+
+ dword = pci_read_config32(MCHDEV, DRC);
+ dword &= 0xffcef8f7;
+ dword |= 0x00210008;
+ pci_write_config32(MCHDEV, DRC, dword);
+
+ /* Undocumented */
+ pci_write_config8(MCHDEV, 0x88, 0x80);
+
+ /* Undocumented. Set much later in vendor BIOS. */
+ byte = pci_read_config8(MCHDEV, 0xd9);
+ byte &= ~0x60;
+ pci_write_config8(MCHDEV, 0xd9, byte);
+
+ uint8_t revision = pci_read_config8(MCHDEV, 0x08);
+ if (revision >= 3)
+ d060_control(D060_CMD_1);
+}
+
+static int e7505_mch_is_ready(void)
+{
+ uint32_t dword = pci_read_config32(MCHDEV, DRC);
+ return !!(dword & DRC_DONE);
+}
+
+void sdram_initialize(void)
+{
+ static const struct mem_controller memctrl[] = {
+ {
+ .d0 = PCI_DEV(0, 0, 0),
+ .d0f1 = PCI_DEV(0, 0, 1),
+ .channel0 = { 0x50, 0x52, 0, 0 },
+ .channel1 = { 0x51, 0x53, 0, 0 },
+ },
+ };
+
+ /* If this is a warm boot, some initialisation can be skipped */
+ if (!e7505_mch_is_ready()) {
+
+ /* The real MCH initialisation. */
+ timestamp_add_now(TS_INITRAM_START);
+
+ sdram_set_registers(memctrl);
+ sdram_set_spd_registers(memctrl);
+ sdram_enable(memctrl);
+
+ /* Hook for post ECC scrub settings and debug. */
+ sdram_post_ecc(memctrl);
+
+ timestamp_add_now(TS_INITRAM_END);
+ }
+
+ printk(BIOS_DEBUG, "SDRAM is up.\n");
+}
diff --git a/src/northbridge/intel/e7505/raminit.h b/src/northbridge/intel/e7505/raminit.h
new file mode 100644
index 0000000000..1e0128ce72
--- /dev/null
+++ b/src/northbridge/intel/e7505/raminit.h
@@ -0,0 +1,24 @@
+/* SPDX-License-Identifier: GPL-2.0-only */
+
+#ifndef RAMINIT_H
+#define RAMINIT_H
+
+#include <stdint.h>
+
+#define MAX_DIMM_SOCKETS_PER_CHANNEL 4
+#define MAX_NUM_CHANNELS 2
+#define MAX_DIMM_SOCKETS (MAX_NUM_CHANNELS * MAX_DIMM_SOCKETS_PER_CHANNEL)
+
+struct mem_controller {
+ pci_devfn_t d0, d0f1; // PCI bus/device/fcns of E7501 memory controller
+
+ // SMBus addresses of DIMM slots for each channel,
+ // in order from closest to MCH to furthest away
+ // 0 == not present
+ uint16_t channel0[MAX_DIMM_SOCKETS_PER_CHANNEL];
+ uint16_t channel1[MAX_DIMM_SOCKETS_PER_CHANNEL];
+};
+
+void sdram_initialize(void);
+
+#endif /* RAMINIT_H */
diff --git a/src/northbridge/intel/e7505/romstage.c b/src/northbridge/intel/e7505/romstage.c
new file mode 100644
index 0000000000..df10f9dbcf
--- /dev/null
+++ b/src/northbridge/intel/e7505/romstage.c
@@ -0,0 +1,19 @@
+/* SPDX-License-Identifier: GPL-2.0-only */
+
+#include <cbmem.h>
+#include <arch/romstage.h>
+
+#include <southbridge/intel/i82801dx/i82801dx.h>
+#include <northbridge/intel/e7505/raminit.h>
+
+void mainboard_romstage_entry(void)
+{
+ /* Perform some early chipset initialization required
+ * before RAM initialization can work
+ */
+ i82801dx_early_init();
+
+ sdram_initialize();
+
+ cbmem_recovery(0);
+}