diff options
author | Nico Huber <nico.h@gmx.de> | 2019-08-11 13:56:30 +0200 |
---|---|---|
committer | Felix Held <felix-coreboot@felixheld.de> | 2023-01-26 13:28:41 +0000 |
commit | 0c314f9c7e1b3c39ad8b4c1f7cf0f72bdcaf8ff1 (patch) | |
tree | d56d5916781b64e7045cc350283973cff5c73136 /src/northbridge/intel | |
parent | df4fa45ce4fe59ddd339e7837fefa504fb34cc40 (diff) |
nb/intel/gm45: Wedge DDR2 SPD support in
Add initial support for DDR2. This also changes GM45 raminit to
internally work in units of 1/256 ns for both DDR2 and DDR3 instead of
the 1/8 ns MTB assumed for DDR3, which simplifies the handling of time
values. DDR3 time values are thus scaled by a factor of 32 accordingly.
TODO:
- DDR2 JEDEC init
- Memory IO init
- Register programming
TEST: DDR2 systems boot (with the rest of the patch train)
- Tested on a Dell Latitude E6400
- Tested on a Compal JHL90
TEST: Ensure DDR3 systems still boot
- Tested on a Thinkpad X200
Change-Id: I265938d58c30264fd5d4f7b89da7b689058b8cf8
Signed-off-by: Nico Huber <nico.h@gmx.de>
Reviewed-on: https://review.coreboot.org/c/coreboot/+/34826
Reviewed-by: Angel Pons <th3fanbus@gmail.com>
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>
Diffstat (limited to 'src/northbridge/intel')
-rw-r--r-- | src/northbridge/intel/gm45/gm45.h | 2 | ||||
-rw-r--r-- | src/northbridge/intel/gm45/raminit.c | 198 |
2 files changed, 181 insertions, 19 deletions
diff --git a/src/northbridge/intel/gm45/gm45.h b/src/northbridge/intel/gm45/gm45.h index d610f317e4..c5c17a6a0d 100644 --- a/src/northbridge/intel/gm45/gm45.h +++ b/src/northbridge/intel/gm45/gm45.h @@ -111,7 +111,7 @@ typedef struct { int txt_enabled; int cores; gmch_gfx_t gfx_type; - int max_ddr2_mhz; + int max_ddr2_mt; int max_ddr3_mt; fsb_clock_t max_fsb; int max_fsb_mhz; diff --git a/src/northbridge/intel/gm45/raminit.c b/src/northbridge/intel/gm45/raminit.c index 4196edf440..62785d3735 100644 --- a/src/northbridge/intel/gm45/raminit.c +++ b/src/northbridge/intel/gm45/raminit.c @@ -57,8 +57,8 @@ void get_gmch_info(sysinfo_t *sysinfo) printk(BIOS_SPEW, "AMT enabled\n"); } - sysinfo->max_ddr2_mhz = (capid & (1<<(53-32)))?667:800; - printk(BIOS_SPEW, "capable of DDR2 of %d MHz or lower\n", sysinfo->max_ddr2_mhz); + sysinfo->max_ddr2_mt = (capid & (1<<(53-32)))?667:800; + printk(BIOS_SPEW, "capable of DDR2 of %d MHz or lower\n", sysinfo->max_ddr2_mt); if (!(capid & (1<<(48-32)))) { printk(BIOS_SPEW, "VT-d enabled\n"); @@ -224,6 +224,58 @@ static int test_dimm(sysinfo_t *const sysinfo, } /* This function dies if dimm is unsuitable for the chipset. */ +static void verify_ddr2_dimm(sysinfo_t *const sysinfo, int dimm) +{ + if (!test_dimm(sysinfo, dimm, 20, 0x04, 0x04)) + die("Chipset only supports SO-DIMM\n"); + + if (!test_dimm(sysinfo, dimm, 6, 0xff, 0x40) || + !test_dimm(sysinfo, dimm, 11, 0xff, 0x00)) + die("Chipset doesn't support ECC RAM\n"); + + if (!test_dimm(sysinfo, dimm, 5, 0x07, 0) && + !test_dimm(sysinfo, dimm, 5, 0x07, 1)) + die("Chipset wants single or dual ranked DIMMs\n"); + + /* + * Generally supports: + * x8/x16 + * 4 or 8 banks + * 10 column address bits + * 13, 14 or 15 (x8 only) row address bits + * + * FIXME: There seems to be an exception for 256Gb x16 chips. Not + * covered by the numbers above (9 column address bits?). + */ + if (!test_dimm(sysinfo, dimm, 13, 0xff, 8) && + !test_dimm(sysinfo, dimm, 13, 0xff, 16)) + die("Chipset requires x8 or x16 width\n"); + + if (!test_dimm(sysinfo, dimm, 17, 0xff, 4) && + !test_dimm(sysinfo, dimm, 17, 0xff, 8)) + die("Chipset requires 4 or 8 banks\n"); + + if (!test_dimm(sysinfo, dimm, 4, 0xff, 10)) + die("Chipset requires 10 column address bits\n"); + + if (!test_dimm(sysinfo, dimm, 3, 0xff, 13) && + !test_dimm(sysinfo, dimm, 3, 0xff, 14) && + !(test_dimm(sysinfo, dimm, 3, 0xff, 15) && + test_dimm(sysinfo, dimm, 13, 0xff, 8))) + die("Chipset requires 13, 14 or 15 (with x8) row address bits"); +} + +/* For every detected DIMM, test if it's suitable for the chipset. */ +static void verify_ddr2(sysinfo_t *const sysinfo, int mask) +{ + int cur; + for (cur = 0; mask; mask >>= 1, ++cur) { + if (mask & 1) + verify_ddr2_dimm(sysinfo, cur); + } +} + +/* This function dies if dimm is unsuitable for the chipset. */ static void verify_ddr3_dimm(sysinfo_t *const sysinfo, int dimm) { if (!test_dimm(sysinfo, dimm, 3, 15, 3)) @@ -281,7 +333,7 @@ static void verify_ddr3(sysinfo_t *const sysinfo, int mask) typedef struct { int dimm_mask; - struct { + struct spd_dimminfo { unsigned int rows; unsigned int cols; unsigned int chip_capacity; @@ -299,6 +351,105 @@ typedef struct { unsigned int raw_card; } channel[2]; } spdinfo_t; +/** + * \brief Decode SPD tck cycle time + * + * Decodes a raw SPD data from a DDR2 DIMM. + * Returns cycle time in 1/256th ns. + */ +static unsigned int spd_decode_tck_time(u8 c) +{ + u8 high, low; + + high = c >> 4; + + switch (c & 0xf) { + case 0xa: + low = 25; + break; + case 0xb: + low = 33; + break; + case 0xc: + low = 66; + break; + case 0xd: + low = 75; + break; + case 0xe: + case 0xf: + die("Invalid tck setting. lower nibble is 0x%x\n", c & 0xf); + default: + low = (c & 0xf) * 10; + } + + return ((high * 100 + low) << 8) / 100; +} +static void collect_ddr2_dimm(struct spd_dimminfo *const di, const int smb_addr) +{ + static const int tCK_offsets[] = { 9, 23, 25 }; + + di->rows = smbus_read_byte(smb_addr, 3); + di->cols = smbus_read_byte(smb_addr, 4); + di->banks = smbus_read_byte(smb_addr, 17); + di->width = smbus_read_byte(smb_addr, 13) / 8; /* in bytes */ + + /* 0: 256Mb .. 3: 2Gb */ + di->chip_capacity = + di->rows + di->cols + + (di->width == 1 ? 3 : 4) /* 1B: 2^3 bits, 2B: 2^4 bits */ + + (di->banks == 4 ? 2 : 3) /* 4 banks: 2^2, 8 banks: 2^3 */ + - 28; + + di->page_size = di->width * (1 << di->cols); /* in bytes */ + + di->ranks = (smbus_read_byte(smb_addr, 5) & 7) + 1; + + di->cas_latencies = smbus_read_byte(smb_addr, 18); + /* assuming tCKmin for the highest CAS is the absolute minimum */ + di->tCKmin = spd_decode_tck_time(smbus_read_byte(smb_addr, 9)); + + /* try to reconstruct tAAmin from available data (I hate DDR2 SPDs) */ + unsigned int i; + unsigned int cas = 7; + di->tAAmin = UINT32_MAX; /* we don't have UINT_MAX? */ + for (i = 0; i < ARRAY_SIZE(tCK_offsets); ++i, --cas) { + for (; cas > 1; --cas) + if (di->cas_latencies & (1 << cas)) + break; + if (cas <= 1) + break; + + const unsigned int tCK_enc = + smbus_read_byte(smb_addr, tCK_offsets[i]); + const unsigned int tAA = spd_decode_tck_time(tCK_enc) * cas; + if (tAA < di->tAAmin) + di->tAAmin = tAA; + } + + /* convert to 1/256ns */ + di->tRAS = smbus_read_byte(smb_addr, 30) << 8; /* given in ns */ + di->tRP = smbus_read_byte(smb_addr, 27) << 6; /* given in 1/4ns */ + di->tRCD = smbus_read_byte(smb_addr, 29) << 6; /* given in 1/4ns */ + di->tWR = smbus_read_byte(smb_addr, 36) << 6; /* given in 1/4ns */ + + di->raw_card = 0; /* Use same path as for DDR3 type A. */ +} +/* + * This function collects RAM characteristics from SPD, assuming that RAM + * is generally within chipset's requirements, since verify_ddr2() passed. + */ +static void collect_ddr2(sysinfo_t *const sysinfo, spdinfo_t *const config) +{ + int cur; + for (cur = 0; cur < 2; ++cur) { + if (config->dimm_mask & (1 << (2 * cur))) { + collect_ddr2_dimm(&config->channel[cur], + sysinfo->spd_map[2 * cur]); + } + } +} + /* * This function collects RAM characteristics from SPD, assuming that RAM * is generally within chipset's requirements, since verify_ddr3() passed. @@ -325,18 +476,18 @@ static void collect_ddr3(sysinfo_t *const sysinfo, spdinfo_t *const config) config->channel[cur].cas_latencies = ((smbus_read_byte(smb_addr, 15) << 8) | smbus_read_byte(smb_addr, 14)) << 4; /* so bit x is CAS x */ - config->channel[cur].tAAmin = smbus_read_byte(smb_addr, 16); /* in MTB */ - config->channel[cur].tCKmin = smbus_read_byte(smb_addr, 12); /* in MTB */ + config->channel[cur].tAAmin = smbus_read_byte(smb_addr, 16) * 32; /* convert from MTB to 1/256 ns */ + config->channel[cur].tCKmin = smbus_read_byte(smb_addr, 12) * 32; /* convert from MTB to 1/256 ns */ config->channel[cur].width = smbus_read_byte(smb_addr, 7) & 7; config->channel[cur].page_size = config->channel[cur].width * (1 << config->channel[cur].cols); /* in Bytes */ tmp = smbus_read_byte(smb_addr, 21); - config->channel[cur].tRAS = smbus_read_byte(smb_addr, 22) | ((tmp & 0xf) << 8); - config->channel[cur].tRP = smbus_read_byte(smb_addr, 20); - config->channel[cur].tRCD = smbus_read_byte(smb_addr, 18); - config->channel[cur].tWR = smbus_read_byte(smb_addr, 17); + config->channel[cur].tRAS = (smbus_read_byte(smb_addr, 22) | ((tmp & 0xf) << 8)) * 32; + config->channel[cur].tRP = smbus_read_byte(smb_addr, 20) * 32; + config->channel[cur].tRCD = smbus_read_byte(smb_addr, 18) * 32; + config->channel[cur].tWR = smbus_read_byte(smb_addr, 17) * 32; config->channel[cur].raw_card = smbus_read_byte(smb_addr, 62) & 0x1f; } @@ -418,10 +569,13 @@ static unsigned int find_common_clock_cas(sysinfo_t *const sysinfo, case FSB_CLOCK_667MHz: fsb_mhz = 667; break; } - unsigned int clock = 8000 / tCKmin; - if ((clock > sysinfo->max_ddr3_mt / 2) || (clock > fsb_mhz / 2)) { - int new_clock = MIN(sysinfo->max_ddr3_mt / 2, fsb_mhz / 2); - printk(BIOS_SPEW, "DIMMs support %d MHz, but chipset only runs at up to %d. Limiting...\n", + unsigned int clock = 256000 / tCKmin; + const unsigned int max_ddr_clock = (sysinfo->spd_type == DDR2) + ? sysinfo->max_ddr2_mt / 2 + : sysinfo->max_ddr3_mt / 2; + if ((clock > max_ddr_clock) || (clock > fsb_mhz / 2)) { + int new_clock = MIN(max_ddr_clock, fsb_mhz / 2); + printk(BIOS_INFO, "DIMMs support %d MHz, but chipset only runs at up to %d. Limiting...\n", clock, new_clock); clock = new_clock; } @@ -433,13 +587,13 @@ static unsigned int find_common_clock_cas(sysinfo_t *const sysinfo, while (1) { if (!clock) die("Couldn't find compatible clock / CAS settings.\n"); - tCKproposed = 8000 / clock; + tCKproposed = 256000 / clock; CAS = DIV_ROUND_UP(tAAmin, tCKproposed); printk(BIOS_SPEW, "Trying CAS %u, tCK %u.\n", CAS, tCKproposed); for (; CAS <= DDR3_MAX_CAS; ++CAS) if (cas_latencies & (1 << CAS)) break; - if ((CAS <= DDR3_MAX_CAS) && (CAS * tCKproposed < 160)) { + if ((CAS <= DDR3_MAX_CAS) && (CAS * tCKproposed < 32 * 160)) { /* Found good CAS. */ printk(BIOS_SPEW, "Found compatible clock / CAS pair: %u / %u.\n", clock, CAS); break; @@ -533,7 +687,9 @@ static void calculate_derived_timings(sysinfo_t *const sysinfo, /* Refresh rate is fixed. */ unsigned int tWL; - if (sysinfo->selected_timings.mem_clock == MEM_CLOCK_1067MT) { + if (sysinfo->spd_type == DDR2) { + tWL = sysinfo->selected_timings.CAS - 1; + } else if (sysinfo->selected_timings.mem_clock == MEM_CLOCK_1067MT) { tWL = 6; } else { tWL = 5; @@ -594,7 +750,8 @@ static void collect_dimm_config(sysinfo_t *const sysinfo) printk(BIOS_SPEW, "DDR mask %x, DDR %d\n", spdinfo.dimm_mask, sysinfo->spd_type); if (sysinfo->spd_type == DDR2) { - die("DDR2 not supported at this time.\n"); + verify_ddr2(sysinfo, spdinfo.dimm_mask); + collect_ddr2(sysinfo, &spdinfo); } else if (sysinfo->spd_type == DDR3) { verify_ddr3(sysinfo, spdinfo.dimm_mask); collect_ddr3(sysinfo, &spdinfo); @@ -621,7 +778,7 @@ static void collect_dimm_config(sysinfo_t *const sysinfo) spdinfo.channel[i].width, spdinfo.channel[i].page_size, spdinfo.channel[i].banks, spdinfo.channel[i].ranks, spdinfo.channel[i].tAAmin, spdinfo.channel[i].tCKmin, - 8000 / spdinfo.channel[i].tCKmin, spdinfo.channel[i].cas_latencies); + 256000 / spdinfo.channel[i].tCKmin, spdinfo.channel[i].cas_latencies); } } @@ -660,6 +817,9 @@ static void collect_dimm_config(sysinfo_t *const sysinfo) sysinfo->selected_timings.channel_mode = CHANNEL_MODE_DUAL_INTERLEAVED; else sysinfo->selected_timings.channel_mode = CHANNEL_MODE_SINGLE; + + if (sysinfo->spd_type == DDR2) + die("DDR2 support not complete yet\n"); } static void reset_on_bad_warmboot(void) @@ -825,6 +985,7 @@ static void configure_dram_control_mode(const timings_t *const timings, const di cxdrc |= CxDRC0_RANKEN(r); cxdrc = (cxdrc & ~CxDRC0_RMS_MASK) | /* Always 7.8us for DDR3: */ + /* FIXME DDR2: SPD+12? */ CxDRC0_RMS_78US; mchbar_write32(mchbar, cxdrc); @@ -992,6 +1153,7 @@ static void dram_program_timings(const timings_t *const timings) mchbar_write32(CxDRT5_MCHBAR(i), reg); reg = mchbar_read32(CxDRT6_MCHBAR(i)); + /* FIXME DDR2: SPD+12? */ reg = (reg & ~(0xffff << 16)) | (0x066a << 16); /* always 7.8us refresh rate for DDR3 */ reg |= (1 << 2); mchbar_write32(CxDRT6_MCHBAR(i), reg); |