diff --git a/src/include/spd_cache.h b/src/include/spd_cache.h new file mode 100644 index 0000000000..3270defba8 --- /dev/null +++ b/src/include/spd_cache.h @@ -0,0 +1,23 @@ +/* SPDX-License-Identifier: GPL-2.0-only */ +/* This file is part of the coreboot project. */ + +#ifndef __SPD_CACHE_H +#define __SPD_CACHE_H + +#include + +#define SPD_CACHE_FMAP_NAME "RW_SPD_CACHE" +#define SC_SPD_NUMS (CONFIG_DIMM_MAX) +#define SC_SPD_OFFSET(n) (CONFIG_DIMM_SPD_SIZE * n) +#define SC_CRC_OFFSET (CONFIG_DIMM_MAX * CONFIG_DIMM_SPD_SIZE) +#define SC_SPD_TOTAL_LEN (CONFIG_DIMM_MAX * CONFIG_DIMM_SPD_SIZE) +#define SC_SPD_LEN (CONFIG_DIMM_SPD_SIZE) +#define SC_CRC_LEN (sizeof(uint16_t)) + +enum cb_err update_spd_cache(struct spd_block *blk); +enum cb_err load_spd_cache(uint8_t **spd_cache, size_t *spd_cache_sz); +bool spd_cache_is_valid(uint8_t *spd_cache, size_t spd_cache_sz); +bool check_if_dimm_changed(u8 *spd_cache, struct spd_block *blk); +enum cb_err spd_fill_from_cache(uint8_t *spd_cache, struct spd_block *blk); + +#endif diff --git a/src/lib/Makefile.inc b/src/lib/Makefile.inc index 1fed543f70..b6d318e7a3 100644 --- a/src/lib/Makefile.inc +++ b/src/lib/Makefile.inc @@ -345,3 +345,5 @@ spd.bin-type := spd endif ramstage-y += uuid.c + +romstage-$(CONFIG_ROMSTAGE_SPD_SMBUS) += spd_cache.c diff --git a/src/lib/spd_cache.c b/src/lib/spd_cache.c new file mode 100644 index 0000000000..71dfaf1024 --- /dev/null +++ b/src/lib/spd_cache.c @@ -0,0 +1,221 @@ +/* SPDX-License-Identifier: GPL-2.0-only */ +/* This file is part of the coreboot project. */ + +#include +#include +#include +#include +#include +#include +#include + +/* + * SPD_CACHE layout + * +==========+ offset 0x00 + * |DIMM 1 SPD| SPD data length is CONFIG_DIMM_SPD_SIZE. + * +----------+ offset CONFIG_DIMM_SPD_SIZE * 1 + * |DIMM 2 SPD| + * +----------+ offset CONFIG_DIMM_SPD_SIZE * 2 + * ... + * +----------+ offset CONFIG_DIMM_SPD_SIZE * (N -1) + * |DIMM N SPD| N = CONFIG_DIMM_MAX + * +----------+ offset CONFIG_DIMM_SPD_SIZE * CONFIG_DIMM_MAX + * | CRC 16 | Use to verify the data correctness. + * +==========+ + * + * The size of the RW_SPD_CACHE needs to be aligned with 4KiB. + */ + +/* + * Use to update SPD cache. + * *blk : the new SPD data will be stash into the cache. + * + * return CB_SUCCESS , update SPD cache successfully. + * return CB_ERR , update SPD cache unsuccessfully and the cache is invalid + */ +enum cb_err update_spd_cache(struct spd_block *blk) +{ + struct region_device rdev; + uint16_t data_crc = 0; + int i, j; + + assert(blk->len <= SC_SPD_LEN); + + if (fmap_locate_area_as_rdev_rw(SPD_CACHE_FMAP_NAME, &rdev)) { + printk(BIOS_ERR, "SPD_CACHE: Cannot access %s region\n", SPD_CACHE_FMAP_NAME); + return CB_ERR; + } + + /* Erase whole area, it's for align with 4KiB which is the size of SPI rom sector. */ + if (rdev_eraseat(&rdev, 0, region_device_sz(&rdev)) < 0) { + printk(BIOS_ERR, "SPD_CACHE: Cannot erase %s region\n", SPD_CACHE_FMAP_NAME); + return CB_ERR; + } + + /* Write SPD data */ + for (i = 0; i < SC_SPD_NUMS; i++) { + if (blk->spd_array[i] == NULL) { + /* If DIMM is not present, we calculate the CRC with 0xff. */ + for (j = 0; j < SC_SPD_LEN; j++) + data_crc = crc16_byte(data_crc, 0xff); + } else { + if (rdev_writeat(&rdev, blk->spd_array[i], SC_SPD_OFFSET(i), blk->len) + < 0) { + printk(BIOS_ERR, "SPD_CACHE: Cannot write SPD data at %d\n", + SC_SPD_OFFSET(i)); + return CB_ERR; + } + + for (j = 0; j < blk->len; j++) + data_crc = crc16_byte(data_crc, blk->spd_array[i][j]); + + /* If the blk->len < SC_SPD_LEN, we calculate the CRC with 0xff. */ + if (blk->len < SC_SPD_LEN) + for (j = 0; j < (SC_SPD_LEN - (blk->len)); j++) + data_crc = crc16_byte(data_crc, 0xff); + } + } + + /* Write the crc16 */ + /* It must be the last step to ensure that the data is written correctly */ + if (rdev_writeat(&rdev, &data_crc, SC_CRC_OFFSET, SC_CRC_LEN) < 0) { + printk(BIOS_ERR, "SPD_CACHE: Cannot write crc at 0x%04x\n", SC_CRC_OFFSET); + return CB_ERR; + } + return CB_SUCCESS; +} + +/* + * Locate the RW_SPD_CACHE area in the fmap and read SPD_CACHE data. + * return CB_SUCCESS ,if the SPD_CACHE data is ready and the pointer return at *spd_cache. + * return CB_ERR ,if it cannot locate RW_SPD_CACHE area in the fmap or data cannot be read. + */ +enum cb_err load_spd_cache(uint8_t **spd_cache, size_t *spd_cache_sz) +{ + struct region_device rdev; + + if (fmap_locate_area_as_rdev(SPD_CACHE_FMAP_NAME, &rdev) < 0) { + printk(BIOS_ERR, "SPD_CACHE: Cannot find %s region\n", SPD_CACHE_FMAP_NAME); + return CB_ERR; + } + + /* Assume boot device is memory mapped. */ + assert(CONFIG(BOOT_DEVICE_MEMORY_MAPPED)); + *spd_cache = rdev_mmap_full(&rdev); + + if (*spd_cache == NULL) + return CB_ERR; + + *spd_cache_sz = region_device_sz(&rdev); + + /* SPD cache found */ + printk(BIOS_INFO, "SPD_CACHE: cache found, size 0x%zx\n", *spd_cache_sz); + + return CB_SUCCESS; +} + +/* Use to verify the cache data is valid. */ +bool spd_cache_is_valid(uint8_t *spd_cache, size_t spd_cache_sz) +{ + uint16_t data_crc = 0; + int i; + + if (spd_cache_sz < SC_SPD_TOTAL_LEN + SC_CRC_LEN) + return false; + + /* Check the spd_cache crc */ + for (i = 0; i < SC_SPD_TOTAL_LEN; i++) + data_crc = crc16_byte(data_crc, *(spd_cache + i)); + + return *(uint16_t *)(spd_cache + SC_CRC_OFFSET) == data_crc; +} + +/* + * Check if the DIMM is preset in cache. + * return true , DIMM is present. + * return false, DIMM is not present. + */ +static bool get_cached_dimm_present(uint8_t *spd_cache, uint8_t idx) +{ + if (*(uint16_t *)(spd_cache + SC_SPD_OFFSET(idx)) == 0xffff) + return false; + else + return true; +} + +/* + * Use to check if the SODIMM is changed. + * spd_cache : it's a valid SPD cache. + * blk : it must include the smbus addresses of SODIMM. + */ +bool check_if_dimm_changed(u8 *spd_cache, struct spd_block *blk) +{ + int i; + u32 sn; + bool dimm_present_in_cache; + bool dimm_changed = false; + /* Check if the dimm is the same with last system boot. */ + for (i = 0; i < SC_SPD_NUMS && dimm_changed == false; i++) { + /* Return true if any error happened here. */ + if (get_spd_sn(blk->addr_map[i], &sn) == CB_ERR) + return true; + dimm_present_in_cache = get_cached_dimm_present(spd_cache, i); + /* Dimm is not present now. */ + if (sn == 0xffffffff) { + if (dimm_present_in_cache == false) + printk(BIOS_NOTICE, "SPD_CACHE: DIMM%d is not present\n", i); + else { + printk(BIOS_NOTICE, "SPD_CACHE: DIMM%d lost\n", i); + dimm_changed = true; + } + } else { /* Dimm is present now. */ + if (dimm_present_in_cache == true) { + if (memcmp(&sn, spd_cache + SC_SPD_OFFSET(i) + DDR4_SPD_SN_OFF, + SPD_SN_LEN) == 0) + printk(BIOS_NOTICE, "SPD_CACHE: DIMM%d is the same\n", + i); + else { + printk(BIOS_NOTICE, "SPD_CACHE: DIMM%d is new one\n", + i); + dimm_changed = true; + } + } else { + printk(BIOS_NOTICE, "SPD_CACHE: DIMM%d is new one\n", i); + dimm_changed = true; + } + } + } + return dimm_changed; +} + +/* Use to fill the struct spd_block with cache data.*/ +enum cb_err spd_fill_from_cache(uint8_t *spd_cache, struct spd_block *blk) +{ + int i; + u8 dram_type; + + /* Find the first present SPD */ + for (i = 0; i < SC_SPD_NUMS; i++) + if (get_cached_dimm_present(spd_cache, i) == true) + break; + + if (i == SC_SPD_NUMS) { + printk(BIOS_ERR, "SPD_CACHE: No DIMM is present.\n"); + return CB_ERR; + } + + dram_type = *(spd_cache + SC_SPD_OFFSET(i) + SPD_DRAM_TYPE); + + if (dram_type == SPD_DRAM_DDR4) + blk->len = SPD_PAGE_LEN_DDR4; + else + blk->len = SPD_PAGE_LEN; + + for (i = 0; i < SC_SPD_NUMS; i++) + if (get_cached_dimm_present(spd_cache, i) == true) + blk->spd_array[i] = spd_cache + SC_SPD_OFFSET(i); + else + blk->spd_array[i] = NULL; + + return CB_SUCCESS; +}