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Diffstat (limited to 'src/northbridge/intel/i440lx/raminit.c')
-rw-r--r-- | src/northbridge/intel/i440lx/raminit.c | 455 |
1 files changed, 455 insertions, 0 deletions
diff --git a/src/northbridge/intel/i440lx/raminit.c b/src/northbridge/intel/i440lx/raminit.c new file mode 100644 index 0000000000..4c171ef92d --- /dev/null +++ b/src/northbridge/intel/i440lx/raminit.c @@ -0,0 +1,455 @@ +/* + * This file is part of the coreboot project. + * + * Copyright (C) 2007-2008 Uwe Hermann <uwe@hermann-uwe.de> + * Copyright (C) 2009 Maciej Pijanka <maciej.pijanka@gmail.com> + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License as published by + * the Free Software Foundation; either version 2 of the License, or + * (at your option) any later version. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + * + * You should have received a copy of the GNU General Public License + * along with this program; if not, write to the Free Software + * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA + */ + +#include <spd.h> +#include <sdram_mode.h> +#include <delay.h> +#include <stdlib.h> +#include "i440lx.h" + +/*----------------------------------------------------------------------------- +Macros and definitions. +-----------------------------------------------------------------------------*/ + +/* Uncomment this to enable debugging output. */ + +/* Debugging macros. */ +#if defined(DEBUG_RAM_SETUP) +#define PRINT_DEBUG(x) print_debug(x) +#define PRINT_DEBUG_HEX8(x) print_debug_hex8(x) +#define PRINT_DEBUG_HEX16(x) print_debug_hex16(x) +#define PRINT_DEBUG_HEX32(x) print_debug_hex32(x) +#define DUMPNORTH() dump_pci_device(PCI_DEV(0, 0, 0)) +#else +#define PRINT_DEBUG(x) +#define PRINT_DEBUG_HEX8(x) +#define PRINT_DEBUG_HEX16(x) +#define PRINT_DEBUG_HEX32(x) +#define DUMPNORTH() +#endif + +#define NB PCI_DEV(0, 0, 0) + +/* DRAMXC[7:5] - DRAM extended control register (SMS). */ +#define RAM_COMMAND_NORMAL 0x0 +#define RAM_COMMAND_NOP 0x1 // (NOPCE) +#define RAM_COMMAND_PRECHARGE 0x2 // ABPCE +#define RAM_COMMAND_MRS 0x3 // MRSCE +#define RAM_COMMAND_CBR 0x4 // CBRC +// rest are reserved + +/* Table format: register, bitmask, value. */ +static const long register_values[] = { + // ~0x02 == bit 9 + // 0x04 == bit 10 + // BASE is 0x8A but we dont want bit 9 or 10 have ENABLED so 0x8C + PACCFG + 1, 0x38, 0x8c, + + DBC, 0x00, 0xC3, + + DRT, 0x00, 0xFF, + DRT+1, 0x00, 0xFF, + + DRAMC, 0x00, 0x00, /* disable refresh for now. */ + DRAMT, 0x00, 0x00, + + PAM0, 0x00, 0x30, // everything is a mem + PAM1, 0x00, 0x33, + PAM2, 0x00, 0x33, + PAM3, 0x00, 0x33, + PAM4, 0x00, 0x33, + PAM5, 0x00, 0x33, + PAM6, 0x00, 0x33, + + /* Set the DRBs to zero for now, this will be fixed later. */ + DRB0, 0x00, 0x00, + DRB1, 0x00, 0x00, + DRB2, 0x00, 0x00, + DRB3, 0x00, 0x00, + DRB4, 0x00, 0x00, + DRB5, 0x00, 0x00, + DRB6, 0x00, 0x00, + DRB7, 0x00, 0x00, + + /* No memory holes. */ + FDHC, 0x00, 0x00, +}; + +/*----------------------------------------------------------------------------- +SDRAM configuration functions. +-----------------------------------------------------------------------------*/ + +/** + * Send the specified RAM command to all DIMMs. + * + * @param command The RAM command to send to the DIMM(s). + */ +static void do_ram_command(u32 command) +{ + int i, caslatency; + u8 dimm_start, dimm_end; + u16 reg16; + u32 addr, addr_offset; + + /* Configure the RAM command. */ + reg16 = pci_read_config16(NB, DRAMXC); + reg16 &= 0xff1f; /* Clear bits 7-5. */ + reg16 |= (u16) (command << 5); /* Write command into bits 7-5. */ + pci_write_config16(NB, DRAMXC, reg16); + + /* + * RAM_COMMAND_NORMAL affects only the memory controller and + * doesn't need to be "sent" to the DIMMs. + */ + if (command == RAM_COMMAND_NORMAL) + return; + + /* Send the RAM command to each row of memory. */ + dimm_start = 0; + for (i = 0; i < (DIMM_SOCKETS * 2); i++) { + addr_offset = 0; + caslatency = 3; /* TODO: Dynamically get CAS latency later. */ + + /* before translation it is + * + * M[02:00] Burst Length + * M[03:03] Burst Type + * M[06:04] Cas Latency + * 000 - Reserved + * 001 - Reserved + * 010 - CAS 2 + * 011 - CAS 3 + * 100 - Reserved + * 101 - Reserved + * 110 - Reserved + * 111 - Reserved + * M[08:07] Op Mode + * Must Be 00b (Defined mode) + * M[09:09] Write Burst Mode + * 0 - Programmed burst length + * 1 - Single location access + * M[11:10] Reserved + * write 0 to ensure compatibility with.... + */ + + /* seems constructed value will be right shifted by 3 bit, thus constructed value + * must be left shifted by 3 + * so possible formula is (caslatency <<4)|(burst_type << 1)|(burst length) + * then << 3 shift to compensate shift in Memory Controller + */ + if (command == RAM_COMMAND_MRS) { + if (caslatency == 3) + addr_offset = 0x1d0; + if (caslatency == 2) + addr_offset = 0x150; + } + + dimm_end = pci_read_config8(NB, DRB + i); + + addr = (dimm_start * 8 * 1024 * 1024) + addr_offset; + if (dimm_end > dimm_start) { +#if 0 + PRINT_DEBUG(" Sending RAM command 0x"); + PRINT_DEBUG_HEX16(reg16); + PRINT_DEBUG(" to 0x"); + PRINT_DEBUG_HEX32(addr); + PRINT_DEBUG("\r\n"); +#endif + + read32(addr); + } + + /* Set the start of the next DIMM. */ + dimm_start = dimm_end; + } +} + +/*----------------------------------------------------------------------------- +DIMM-independant configuration functions. +-----------------------------------------------------------------------------*/ + +static void spd_enable_refresh(void) +{ + uint8_t reg; + + reg = pci_read_config8(NB, DRAMC); + + /* this chipset offer only two choices regarding refresh + * refresh disabled, or refresh normal + */ + + pci_write_config8(NB, DRAMC, reg | 0x01); + reg = pci_read_config8(NB, DRAMC); + + PRINT_DEBUG("spd_enable_refresh: dramc = 0x"); + PRINT_DEBUG_HEX8(reg); + PRINT_DEBUG("\r\n"); +} + +/*----------------------------------------------------------------------------- +Public interface. +-----------------------------------------------------------------------------*/ + +static void northbridge_init(void) +{ + uint32_t reg32; + + reg32 = pci_read_config32(NB, APBASE); + reg32 &= 0xe8000000U; + pci_write_config32(NB, APBASE, reg32); + + #ifdef DEBUG_RAM_SETUP + /* + * apbase dont get set still, no idea what i have doing wrong yet, + * i am almost sure that somehow i set it by mistake once, but can't + * repeat that. + */ + reg32 = pci_read_config32(NB, APBASE); + PRINT_DEBUG("APBASE "); + PRINT_DEBUG_HEX32(reg32); + PRINT_DEBUG("\r\n"); + #endif +} + + +/** + * This routine sets RAM controller inside northbridge to known state + * + */ +static void sdram_set_registers(void) +{ + int i, max; + + /* nice banner with FSB shown? do we have + * any standart policy about such things? + */ +#if 0 + uint16_t reg16; + reg16 = pci_read_config16(NB, PACCFG); + printk_debug("i82443LX Host Freq: 6%C MHz\r\n", (reg16 & 0x4000) ? '0' : '6'); +#endif + + PRINT_DEBUG("Northbridge prior to SDRAM init:\r\n"); + DUMPNORTH(); + + northbridge_init(); + + max = ARRAY_SIZE(register_values); + + /* Set registers as specified in the register_values[] array. */ + for (i = 0; i < max; i += 3) { + uint8_t reg,tmp; + reg = pci_read_config8(NB, register_values[i]); + reg &= register_values[i + 1]; + reg |= register_values[i + 2] & ~(register_values[i + 1]); + pci_write_config8(NB, register_values[i], reg); + + /* + * i am not sure if that is needed, but was usefull + * for me to confirm what got written + */ +#ifdef DEBUG_RAM_SETUP + PRINT_DEBUG(" Set register 0x"); + PRINT_DEBUG_HEX8(register_values[i]); + PRINT_DEBUG(" to 0x"); + PRINT_DEBUG_HEX8(reg); + tmp = pci_read_config8(NB, register_values[i]); + PRINT_DEBUG(" readed 0x"); + PRINT_DEBUG_HEX8(tmp); + if (tmp == reg) { + PRINT_DEBUG(" OK "); + } else { + PRINT_DEBUG(" FAIL "); + } + PRINT_DEBUG("\r\n"); +#endif + } + + PRINT_DEBUG("Northbridge atexit sdram set registers\r\n"); + DUMPNORTH(); +} + + +static void sdram_set_spd_registers(void) +{ + int i; + u16 memsize = 0; + + for (i = 0; i < DIMM_SOCKETS; i++) { + uint16_t ds = 0; // dimm size + int j; + /* this code skips second bank on each socket (no idea how to fix it now) + */ + + PRINT_DEBUG("DIMM"); + PRINT_DEBUG_HEX8(i); + PRINT_DEBUG(" rows: "); + PRINT_DEBUG_HEX8(spd_read_byte(DIMM_SPD_BASE + i, SPD_NUM_DIMM_BANKS) & 0xFF); + PRINT_DEBUG(" rowsize: "); + PRINT_DEBUG_HEX8(spd_read_byte(DIMM_SPD_BASE + i, SPD_DENSITY_OF_EACH_ROW_ON_MODULE) & 0xFF); + PRINT_DEBUG(" modulesize: "); + + j = spd_read_byte(DIMM_SPD_BASE + i, SPD_NUM_DIMM_BANKS); + if (j < 0) + j = 0; + else + ds = j; + + j = spd_read_byte(DIMM_SPD_BASE + i, SPD_DENSITY_OF_EACH_ROW_ON_MODULE); + + if (j < 0) + j = 0; + else + ds = ds * (j >> 1); // convert from 4MB to 8MB units in place + + + /* This is more or less crude hack + * allowing to run this target under qemu (even if that is not really + * same hardware emulated), + * probably some kconfig expert option should be added to enable/disable + * this nicelly + */ +#if 0 + if (ds == 0 && memsize == 0) + ds = 0x8; +#endif + + + // todo: support for bank with not equal sizes as per jedec standart? + + /* + * because density is reported in units of 4Mbyte + * and rows in device are just value, + * and for setting registers we need value in 8Mbyte units + */ + + PRINT_DEBUG_HEX16(ds); + PRINT_DEBUG("\r\n"); + + memsize += ds; + + pci_write_config8(NB, DRB + (2*i), memsize); + pci_write_config8(NB, DRB + (2*i) + 1, memsize); + if (ds > 0) { + /* i have no idea why pci_read_config16 not work for + * me correctly here + */ + ds = pci_read_config8(NB, DRT+1); + ds <<=8; + ds |= pci_read_config8(NB, DRT); + + PRINT_DEBUG("DRT "); + PRINT_DEBUG_HEX16(ds); + + ds &= ~(0x01 << (4 * i)); + + PRINT_DEBUG(" "); + PRINT_DEBUG_HEX16(ds); + PRINT_DEBUG("\r\n"); + + /* + * modify DRT register if current row isn't empty + * code assume its SDRAM plugged (should check if its sdram or EDO, + * edo would have 0x00 as constand instead 0x10 for SDRAM + * also this code is buggy because ignores second row of each dimm socket + */ + + /* and as above write_config16 not work here too) + * pci_write_config16(NB, DRT, j); + */ + + pci_write_config8(NB, DRT+1, ds >> 8); + pci_write_config8(NB, DRT, ds & 0xFF); + } + } + +#if 0 + PRINT_DEBUG("Mem: 0x"); + PRINT_DEBUG_HEX16(memsize * 8); + PRINT_DEBUG(" MB\r\n"); + + if (memsize == 0) { + /* maybe we should use some nice die/hlt sequence with printing on console + * that no memory found, get lost, i can't run? + * maybe such event_handler can be commonly defined routine to decrease + * code duplication? + */ + PRINT_DEBUG("No memory detected via SPD\r\n"); + PRINT_DEBUG("Reverting to hardcoded 64M single side dimm in first bank\r\n"); + } +#endif + + /* Set DRAMC. Don't enable refresh for now. */ + pci_write_config8(NB, DRAMC, 0x00); + + /* Cas latency 3, and other shouldbe properly from spd too */ + pci_write_config8(NB, DRAMT, 0xAC); + + /* TODO? */ + pci_write_config8(NB, PCI_LATENCY_TIMER, 0x40); + + // set drive strength + pci_write_config32(NB, MBSC, 0x00000000); +} + +static void sdram_enable(void) +{ + int i; + + /* 0. Wait until power/voltages and clocks are stable (200us). */ + udelay(200); + + /* 1. Apply NOP. Wait 200 clock cycles (clock might be 60 or 66 Mhz). */ + PRINT_DEBUG("RAM Enable 1: Apply NOP\r\n"); + do_ram_command(RAM_COMMAND_NOP); + udelay(200); + + /* 2. Precharge all. Wait tRP. */ + PRINT_DEBUG("RAM Enable 2: Precharge all\r\n"); + do_ram_command(RAM_COMMAND_PRECHARGE); + udelay(1); + + /* 3. Perform 8 refresh cycles. Wait tRC each time. */ + PRINT_DEBUG("RAM Enable 3: CBR\r\n"); + for (i = 0; i < 8; i++) { + do_ram_command(RAM_COMMAND_CBR); + udelay(1); + } + + /* 4. Mode register set. Wait two memory cycles. */ + PRINT_DEBUG("RAM Enable 4: Mode register set\r\n"); + do_ram_command(RAM_COMMAND_MRS); + udelay(2); + + /* 5. Normal operation. */ + PRINT_DEBUG("RAM Enable 5: Normal operation\r\n"); + do_ram_command(RAM_COMMAND_NORMAL); + udelay(1); + + /* 6. Finally enable refresh. */ + PRINT_DEBUG("RAM Enable 6: Enable refresh\r\n"); + pci_write_config8(NB, DRAMC, 0x01); + spd_enable_refresh(); + udelay(1); + + PRINT_DEBUG("Northbridge following SDRAM init:\r\n"); +} + |