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-rw-r--r--src/northbridge/intel/e7505/raminit.c478
1 files changed, 97 insertions, 381 deletions
diff --git a/src/northbridge/intel/e7505/raminit.c b/src/northbridge/intel/e7505/raminit.c
index e98a04258a..b06f81d3d6 100644
--- a/src/northbridge/intel/e7505/raminit.c
+++ b/src/northbridge/intel/e7505/raminit.c
@@ -100,229 +100,38 @@ static const uint8_t dual_channel_parameters[] = {
SPD_NUM_BANKS_PER_SDRAM
};
- /*
- * Table: constant_register_values
- */
-static const long constant_register_values[] = {
- /* SVID - Subsystem Vendor Identification Register
- * 0x2c - 0x2d
- * [15:00] Subsytem Vendor ID (Indicates system board vendor)
+ /* Comments here are remains of e7501 or even 855PM.
+ * They might be partially (in)correct for e7505.
*/
- /* SID - Subsystem Identification Register
- * 0x2e - 0x2f
- * [15:00] Subsystem ID
- */
- // Not everyone wants to be Super Micro Computer, Inc.
- // The mainboard should set this if desired.
- // 0x2c, 0, (0x15d9 << 0) | (0x3580 << 16),
- /* Undocumented
- * (DRAM Read Timing Control, if similar to 855PM?)
- * 0x80 - 0x81
+ /* (DRAM Read Timing Control, if similar to 855PM?)
+ * 0x80 - 0x81 documented differently for e7505
* This register has something to do with CAS latencies,
* possibily 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
+ *
+ * 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
+ *
+ * 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
+ /* 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
- *
- * PAM - Programmable Attribute Map
- * 0x59 [1:0] Reserved
- * 0x59 [5:4] 0xF0000 - 0xFFFFF
- * 0x5A [1:0] 0xC0000 - 0xC3FFF
- * 0x5A [5:4] 0xC4000 - 0xC7FFF
- * 0x5B [1:0] 0xC8000 - 0xCBFFF
- * 0x5B [5:4] 0xCC000 - 0xCFFFF
- * 0x5C [1:0] 0xD0000 - 0xD3FFF
- * 0x5C [5:4] 0xD4000 - 0xD7FFF
- * 0x5D [1:0] 0xD8000 - 0xDBFFF
- * 0x5D [5:4] 0xDC000 - 0xDFFFF
- * 0x5E [1:0] 0xE0000 - 0xE3FFF
- * 0x5E [5:4] 0xE4000 - 0xE7FFF
- * 0x5F [1:0] 0xE8000 - 0xEBFFF
- * 0x5F [5:4] 0xEC000 - 0xEFFFF
- * 00 == DRAM Disabled (All Access go to memory mapped I/O space)
- * 01 == Read Only (Reads to DRAM, Writes to memory mapped I/O space)
- * 10 == Write Only (Writes to DRAM, Reads to memory mapped I/O space)
- * 11 == Normal (All Access go to DRAM)
- */
-
- // Map all legacy ranges to DRAM
- 0x58, 0xcccccf7f, (0x00 << 0) | (0x30 << 8) | (0x33 << 16) | (0x33 << 24),
- 0x5C, 0xcccccccc, (0x33 << 0) | (0x33 << 8) | (0x33 << 16) | (0x33 << 24),
-
- /* DRB - DRAM Row Boundary Registers
- * 0x60 - 0x6F
- * An array of 8 byte registers, which hold the ending
- * memory address assigned to each pair of DIMMS, in 64MB
- * granularity.
- */
- // Conservatively say each row has 64MB of ram, we will fix this up later
- // NOTE: These defaults allow us to prime all of the DIMMs on the board
- // without jumping through 36-bit adddressing hoops, even if the
- // total memory is > 4 GB. Changing these values may break do_ram_command()!
- 0x60, 0x00000000, (0x01 << 0) | (0x02 << 8) | (0x03 << 16) | (0x04 << 24),
-// 0x64, 0x00000000, (0x05 << 0) | (0x06 << 8) | (0x07 << 16) | (0x08 << 24),
- 0x64, 0x00000000, (0x04 << 0) | (0x04 << 8) | (0x04 << 16) | (0x04 << 24),
-
- /* DRA - DRAM Row Attribute Register
- * 0x70 Row 0,1
- * 0x71 Row 2,3
- * 0x72 Row 4,5
- * 0x73 Row 6,7
- * [7:7] Device width for Odd numbered rows
- * 0 == 8 bits wide x8
- * 1 == 4 bits wide x4
- * [6:4] Row Attributes for Odd numbered rows
- * 010 == 8KB (for dual-channel)
- * 011 == 16KB (for dual-channel)
- * 100 == 32KB (for dual-channel)
- * 101 == 64KB (for dual-channel)
- * Others == Reserved
- * [3:3] Device width for Even numbered rows
- * 0 == 8 bits wide x8
- * 1 == 4 bits wide x4
- * [2:0] Row Attributes for Even numbered rows
- * 010 == 8KB (for dual-channel)
- * 011 == 16KB (for dual-channel)
- * 100 == 32KB (for dual-channel)
- * 101 == 64KB (This page size appears broken)
- * Others == Reserved
- */
- // NOTE: overridden by configure_e7501_row_attributes(), later
- 0x70, 0x00000000, 0,
-
- /* DRT - DRAM Timing Register
- * 0x78
- * [31:30] Reserved
- * [29:29] Back to Back Write-Read Turn Around
- * 0 == 3 clocks between WR-RD commands
- * 1 == 2 clocks between WR-RD commands
- * [28:28] Back to Back Read-Write Turn Around
- * 0 == 5 clocks between RD-WR commands
- * 1 == 4 clocks between RD-WR commands
- * [27:27] Back to Back Read Turn Around
- * 0 == 4 clocks between RD commands
- * 1 == 3 clocks between RD commands
- * [26:24] Read Delay (tRD)
- * 000 == 7 clocks
- * 001 == 6 clocks
- * 010 == 5 clocks
- * Others == Reserved
- * [23:19] Reserved
- * [18:16] DRAM idle timer
- * 000 == infinite
- * 011 == 16 dram clocks
- * 001 == 0 clocks
- * [15:11] Reserved
- * [10:09] Active to Precharge (tRAS)
- * 00 == 7 clocks
- * 01 == 6 clocks
- * 10 == 5 clocks
- * 11 == Reserved
- * [08:06] Reserved
- * [05:04] Cas Latency (tCL)
- * 00 == 2.5 Clocks
- * 01 == 2.0 Clocks
- * 10 == Reserved (was 1.5 Clocks for E7500)
- * 11 == Reserved
- * [03:03] Write Ras# to Cas# Delay (tRCD)
- * 0 == 3 DRAM Clocks
- * 1 == 2 DRAM Clocks
- * [02:01] Read RAS# to CAS# Delay (tRCD)
- * 00 == reserved
- * 01 == reserved
- * 10 == 3 DRAM Clocks
- * 11 == 2 DRAM Clocks
- * [00:00] DRAM RAS# to Precharge (tRP)
- * 0 == 3 DRAM Clocks
- * 1 == 2 DRAM Clocks
*/
- // Some earlier settings:
- /* Most aggressive settings possible */
-// 0x78, 0xc0fff8c4, (1<<29)|(1<<28)|(1<<27)|(2<<24)|(2<<9)|CAS_LATENCY|(1<<3)|(1<<1)|(1<<0),
-// 0x78, 0xc0f8f8c0, (1<<29)|(1<<28)|(1<<27)|(1<<24)|(1<<16)|(2<<9)|CAS_LATENCY|(1<<3)|(3<<1)|(1<<0),
-// 0x78, 0xc0f8f9c0, (1<<29)|(1<<28)|(1<<27)|(1<<24)|(1<<16)|(2<<9)|CAS_LATENCY|(1<<3)|(3<<1)|(1<<0),
-
- // 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.
-// 0x78, 0xD7F8FFFF, (1 << 29) | (1 << 27) | (1 << 16),
- 0x78, 0xC7F8FFFF, (0x03<<16)|(0x28<<24),
-
- /* FIXME why was I attempting to set a reserved bit? */
- /* 0x0100040f */
-
- /* DRC - DRAM Contoller Mode Register
- * 0x7c
- * [31:30] Reserved
- * [29:29] Initialization Complete
- * 0 == Not Complete
- * 1 == Complete
- * [28:23] Reserved
- * [22:22] Channels
- * 0 == Single channel
- * 1 == Dual Channel
- * [21:20] DRAM Data Integrity Mode
- * 00 == Disabled, no ECC
- * 01 == Reserved
- * 10 == Error checking, using chip-kill, with correction
- * 11 == Reserved
- * [19:18] DRB Granularity (Read-Only)
- * 00 == 32 MB quantities (single channel mode)
- * 01 == 64 MB quantities (dual-channel mode)
- * 10 == Reserved
- * 11 == Reserved
- * [17:17] (Intel Undocumented) should always be set to 1 (SJM: comment inconsistent with current setting, below)
- * [16:16] Command Per Clock - Address/Control Assertion Rule (CPC)
- * 0 == 2n Rule
- * 1 == 1n rule
- * [15:11] Reserved
- * [10:08] Refresh mode select
- * 000 == Refresh disabled
- * 001 == Refresh interval 15.6 usec
- * 010 == Refresh interval 7.8 usec
- * 011 == Refresh interval 64 usec
- * 111 == Refresh every 64 clocks (fast refresh)
- * [07:07] Reserved
- * [06:04] Mode Select (SMS)
- * 000 == Reserved (was Self Refresh Mode in E7500)
- * 001 == NOP Command
- * 010 == All Banks Precharge
- * 011 == Mode Register Set
- * 100 == Extended Mode Register Set
- * 101 == Reserved
- * 110 == CBR Refresh
- * 111 == Normal Operation
- * [03:00] Reserved
- */
-// .long 0x7c, 0xffcefcff, (1<<22)|(2 << 20)|(1 << 16)| (0 << 8),
-// .long 0x7c, 0xff8cfcff, (1<<22)|(2 << 20)|(1 << 17)|(1 << 16)| (0 << 8),
-// .long 0x7c, 0xff80fcff, (1<<22)|(2 << 20)|(1 << 18)|(1 << 17)|(1 << 16)| (0 << 8),
-
- // Default to dual-channel mode, ECC, 1-clock address/cmd hold
- // NOTE: configure_e7501_dram_controller_mode() configures further
-// 0x7c, 0xff8ef8ff, (1 << 22) | (2 << 20) | (1 << 16) | (0 << 8),
- 0x7c, 0xffcef8f7, 0x00210008,
-
/* Another Intel undocumented register
* 0x88 - 0x8B
* [31:31] Purpose unknown
@@ -336,118 +145,8 @@ static const long constant_register_values[] = {
* 0 == Normal operation?
* 1 == Reset?
*/
- // NOTE: Some factory BIOSs don't do this.
- // Doesn't seem to matter either way.
- 0x88, 0xffffff00, 0x80,
-
- /* CLOCK_DIS - CK/CK# Disable Register
- * 0x8C
- * [7:7] DDR Frequency
- * 0 == 100 MHz (200 MHz data rate)
- * 1 == 133 MHz (266 MHz data rate)
- * [6:4] Reserved
- * [3:3] CK3
- * 0 == Enable
- * 1 == Disable
- * [2:2] CK2
- * 0 == Enable
- * 1 == Disable
- * [1:1] CK1
- * 0 == Enable
- * 1 == Disable
- * [0:0] CK0
- * 0 == Enable
- * 1 == Disable
- */
- // NOTE: Disable all clocks initially; turn ones we need back on
- // in enable_e7501_clocks()
- 0x8C, 0xfffffff0, 0xf,
-
- /* TOLM - Top of Low Memory Register
- * 0xC4 - 0xC5
- * [15:11] Top of low memory (TOLM)
- * The address below 4GB that should be treated as RAM,
- * on a 128MB granularity.
- * [10:00] Reserved
- */
- /* REMAPBASE - Remap Base Address Regsiter
- * 0xC6 - 0xC7
- * [15:10] Reserved
- * [09:00] Remap Base Address [35:26] 64M aligned
- * Bits [25:0] are assumed to be 0.
- */
-
- // NOTE: TOLM overridden by configure_e7501_ram_addresses()
- 0xc4, 0xfc0007ff, (0x2000 << 0) | (0x3ff << 16),
-
- /* REMAPLIMIT - Remap Limit Address Register
- * 0xC8 - 0xC9
- * [15:10] Reserved
- * [09:00] Remap Limit Address [35:26] 64M aligned
- * When remaplimit < remapbase the remap window is disabled.
- */
- 0xc8, 0xfffffc00, 0,
-
- /* DVNP - Device Not Present Register
- * 0xE0 - 0xE1
- * [15:05] Reserved
- * [04:04] Device 4 Function 1 Present
- * 0 == Present
- * 1 == Absent
- * [03:03] Device 3 Function 1 Present
- * 0 == Present
- * 1 == Absent
- * [02:02] Device 2 Function 1 Present
- * 0 == Present
- * 1 == Absent
- * [01:01] Reserved
- * [00:00] Device 0 Function 1 Present
- * 0 == Present
- * 1 == Absent
- */
-
- // Enable D0:D1, disable D2:F1, D3:F1, D4:F1
-// 0xe0, 0xffffffe2, (1 << 4) | (1 << 3) | (1 << 2) | (0 << 0),
- 0xe0, 0xfffffffa, 0x0,
-
- // Undocumented
- 0xd8, 0xffff9fff, 0x00000000,
-
- // Undocumented - this is pure conjecture based on similarity to 855PM
- /* MCHTST - MCH Test Register
- * 0xF4 - 0xF7
- * [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?
- */
-
-// 0xf4, 0x3f8ffffd, 0x40300002,
-
-#ifdef SUSPICIOUS_LOOKING_CODE
- // SJM: Undocumented.
- // This will access D2:F0:0x50, is this correct??
- 0x1050, 0xffffffcf, 0x00000030,
-#endif
-};
-
- /* DDR RECOMP tables */
-#if 0
-// Slew table for 1x drive?
-static const uint32_t 1x_slew_table[] = {
- 0x44332211, 0xc9776655, 0xffffffff, 0xffffffff,
- 0x22111111, 0x55444332, 0xfffca876, 0xffffffff,
-};
-#endif
+/* DDR RECOMP tables */
// Slew table for 2x drive?
static const uint32_t slew_2x[] = {
0x00000000, 0x76543210, 0xffffeca8, 0xffffffff,
@@ -466,21 +165,13 @@ Delay functions:
/* Estimate that SLOW_DOWN_IO takes about 1 us */
#define SLOW_DOWN_IO inb(0x80)
-static inline void local_udelay(int i)
+static void local_udelay(int i)
{
while (i--) {
SLOW_DOWN_IO;
}
}
-static inline void local_mdelay(int i)
-{
- i *= 1000;
- while (i--) {
- SLOW_DOWN_IO;
- }
-}
-
/* delay for 200us */
#define DO_DELAY local_udelay(200)
#define EXTRA_DELAY DO_DELAY
@@ -524,7 +215,7 @@ typedef enum {
* 1 == Enable
* [00:00] Unknown - not used?
*/
-static inline void mchtest_control(mchtst_cc cmd)
+static void mchtest_control(mchtst_cc cmd)
{
uint32_t dword = pci_read_config32(MCHDEV, MCHTST);
switch (cmd) {
@@ -551,7 +242,7 @@ static inline void mchtest_control(mchtst_cc cmd)
/**
*
*/
-static inline void d060_control(d060_cc cmd)
+static void d060_control(d060_cc cmd)
{
mchtest_control(D060_ENABLE);
uint32_t dword = pci_read_config32(D060DEV, 0xf0);
@@ -570,7 +261,7 @@ static inline void d060_control(d060_cc cmd)
/**
*
*/
-static inline void rcomp_smr_control(rcomp_smr_cc cmd)
+static void rcomp_smr_control(rcomp_smr_cc cmd)
{
uint32_t dword = read32(RCOMP_MMIO + SMRCTL);
switch (cmd) {
@@ -995,6 +686,9 @@ static void do_ram_command(uint8_t command, uint16_t jedec_mode_bits)
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);
@@ -1003,7 +697,7 @@ static void do_ram_command(uint8_t command, uint16_t jedec_mode_bits)
dimm_start_address &= 0x3ffffff;
dimm_start_address |= dimm_start_64M_multiple << 26;
read32(dimm_start_address);
- // Set the start of the next DIMM
+ // Set the start of the next DIMM
dimm_start_64M_multiple = dimm_end_64M_multiple;
}
}
@@ -1756,47 +1450,6 @@ static void RAM_RESET_DDR_PTR(void)
}
/**
- * Set E7501 registers that are either independent of DIMM specifics, or
- * establish default settings that will be overridden when we learn the
- * specifics.
- *
- * This sets PCI configuration registers to known good values based on the
- * table 'constant_register_values', which are a triple of configuration
- * register offset, mask, and bits to set.
- */
-static void ram_set_d0f0_regs(void)
-{
- int i;
- int num_values = ARRAY_SIZE(constant_register_values);
-
- ASSERT((num_values % 3) == 0); // Bad table?
-
- for (i = 0; i < num_values; i += 3) {
-
- uint32_t register_offset = constant_register_values[i];
- uint32_t bits_to_mask = constant_register_values[i + 1];
- uint32_t bits_to_set = constant_register_values[i + 2];
- uint32_t register_value;
-
- // It's theoretically possible to set values for something other than D0:F0,
- // but it's not typically done here
- ASSERT(!(register_offset & 0xFFFFFF00));
-
- // bits_to_mask and bits_to_set should not reference the same bits
- // Again, not strictly an error, but flagged as a potential bug
- ASSERT((bits_to_mask & bits_to_set) == 0);
-
- register_value =
- pci_read_config32(MCHDEV, register_offset);
- register_value &= bits_to_mask;
- register_value |= bits_to_set;
-
- pci_write_config32(MCHDEV, register_offset,
- register_value);
- }
-}
-
-/**
* Copy 64 bytes from one location to another.
*
* @param src_addr TODO
@@ -1822,20 +1475,13 @@ static void write_8dwords(const uint32_t *src_addr, uint32_t dst_addr)
* Comments below are conjecture based on apparent similarity between the
* E7501 and these two chips.
*/
-static void ram_set_rcomp_regs(void)
+static void rcomp_copy_registers(void)
{
uint32_t dword;
- uint8_t strength_control, revision;
+ uint8_t strength_control;
RAM_DEBUG_MESSAGE("Setting RCOMP registers.\n");
- /* Set the RCOMP MMIO base address */
- mchtest_control(RCOMP_BAR_ENABLE);
- pci_write_config32(MCHDEV, SMRBASE, RCOMP_MMIO);
-
- /* Block RCOMP updates while we configure the registers */
- rcomp_smr_control(RCOMP_HOLD);
-
/* Begin to write the RCOMP registers */
write8(RCOMP_MMIO + 0x2c, 0x0);
@@ -1902,7 +1548,6 @@ static void ram_set_rcomp_regs(void)
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);
@@ -1910,18 +1555,27 @@ static void ram_set_rcomp_regs(void)
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, 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);
- revision = pci_read_config8(MCHDEV, 0x08);
+ 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;
@@ -2084,11 +1738,73 @@ static void sdram_set_spd_registers(const struct mem_controller *ctrl)
*/
static void sdram_set_registers(const struct mem_controller *ctrl)
{
- RAM_DEBUG_MESSAGE("Northbridge prior to SDRAM init:\n");
- DUMPNORTH();
+ uint32_t dword;
+ uint16_t word;
+ uint8_t byte;
ram_set_rcomp_regs();
- ram_set_d0f0_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);
+
+#ifdef SUSPICIOUS_LOOKING_CODE
+ /* This will access D2:F0:0x50, is this correct??
+ * Vendor BIOS reads Device ID before this is set.
+ * Undocumented in the p64h2 PCI-X bridge datasheet.
+ */
+ byte = pci_read_config8(PCI_DEV(0,2,0), 0x50);
+ byte &= 0xcf;
+ byte |= 0x30
+ pci_write_config8(PCI_DEV(0,2,0), 0x50, byte);
+#endif
uint8_t revision = pci_read_config8(MCHDEV, 0x08);
if (revision >= 3)