紀錄一下 uboot 讀到的 ocr csd register:

• mmc ocr: 80FF8080
• csd : D00F0032 F5A03A6 FFFFFCFF 92404000

CSD 的 byte order是相反的：

• D00F0032 : 96-127
• 0F5A03A6 : 64-95
• FFFFFCFF: 32-63
• 92404000 : 0-31

跟micro sd 讀到的一樣。 很麻煩，還是用 linux 的 code: #define UNSTUFF_BITS(resp,start,size) \ ({ \ const int __size = size; \ const u32 __mask = (__size < 32 ? 1 << __size : 0) - 1; \ const int __off = 3 - ((start) / 32); \ const int __shft = (start) & 31; \ u32 __res; \ \ __res = resp[__off] >> __shft; \ if (__size + __shft > 32) \ __res |= resp[__off-1] << ((32 - __shft) % 32); \ __res & __mask; \ }) 這樣就可以用比較漂亮的方式： csd_struct = UNSTUFF_BITS(resp, 126, 2); m = UNSTUFF_BITS(resp, 115, 4); e = UNSTUFF_BITS(resp, 112, 3); csd->tacc_ns = (tacc_exp[e] * tacc_mant[m] + 9) / 10; csd->tacc_clks = UNSTUFF_BITS(resp, 104, 8) * 100; m = UNSTUFF_BITS(resp, 99, 4); e = UNSTUFF_BITS(resp, 96, 3); csd->max_dtr = tran_exp[e] * tran_mant[m]; csd->cmdclass = UNSTUFF_BITS(resp, 84, 12); e = UNSTUFF_BITS(resp, 47, 3); m = UNSTUFF_BITS(resp, 62, 12); csd->capacity = (1 + m) << (e + 2); csd->read_blkbits = UNSTUFF_BITS(resp, 80, 4); csd->read_partial = UNSTUFF_BITS(resp, 79, 1); csd->write_misalign = UNSTUFF_BITS(resp, 78, 1); csd->read_misalign = UNSTUFF_BITS(resp, 77, 1); csd->r2w_factor = UNSTUFF_BITS(resp, 26, 3); csd->write_blkbits = UNSTUFF_BITS(resp, 22, 4); csd->write_partial = UNSTUFF_BITS(resp, 21, 1); host->read_bl_len = (1<<9); host->write_bl_len = (1<<9); host->capacity = csd->capacity<<(csd->read_blkbits - 9); CSD 的內榮要看 JEDEC 84-A43 : (http://www.solutioninside.com/~jackiekan/lib/exe/fetch.php?id=dsd2008%3Aindex&cache=cache&media=dsd2008:jedsd84-a43.pdf) command class 在 linux header 有定義： /* * Card Command Classes (CCC) */ #define CCC_BASIC (1<<0) /* (0) Basic protocol functions */ /* (CMD0,1,2,3,4,7,9,10,12,13,15) */ /* (and for SPI, CMD58,59) */ #define CCC_STREAM_READ (1<<1) /* (1) Stream read commands */ /* (CMD11) */ #define CCC_BLOCK_READ (1<<2) /* (2) Block read commands */ /* (CMD16,17,18) */ #define CCC_STREAM_WRITE (1<<3) /* (3) Stream write commands */ /* (CMD20) */ #define CCC_BLOCK_WRITE (1<<4) /* (4) Block write commands */ /* (CMD16,24,25,26,27) */ #define CCC_ERASE (1<<5) /* (5) Ability to erase blocks */ /* (CMD32,33,34,35,36,37,38,39) */ #define CCC_WRITE_PROT (1<<6) /* (6) Able to write protect blocks */ /* (CMD28,29,30) */ #define CCC_LOCK_CARD (1<<7) /* (7) Able to lock down card */ /* (CMD16,CMD42) */ #define CCC_APP_SPEC (1<<8) /* (8) Application specific */ /* (CMD55,56,57,ACMD*) */ #define CCC_IO_MODE (1<<9) /* (9) I/O mode */ /* (CMD5,39,40,52,53) */ #define CCC_SWITCH (1<<10) /* (10) High speed switch */ /* (CMD6,34,35,36,37,50) */ /* (11) Reserved */ /* (CMD?) */ EXT_CSD 的資料更多。 在 linux kernel 的 source code : include/linux/mmc/mmc.h 有一些定義： 用到的 field 也有定義： #define EXT_CSD_BOOT_BUS_WIDTH 177 /* R/W */ #define EXT_CSD_BOOT_CONFIG 179 /* R/W */ #define EXT_CSD_BUS_WIDTH 183 /* R/W */ #define EXT_CSD_BUS_WIDTH_1 0 /* Card is in 1 bit mode */ #define EXT_CSD_BUS_WIDTH_4 1 /* Card is in 4 bit mode */ #define EXT_CSD_BUS_WIDTH_8 2 /* Card is in 8 bit mode */ #define EXT_CSD_BUS_WIDTH_4_DDR 5 /* Card is in 4 bit ddr mode */ #define EXT_CSD_BUS_WIDTH_8_DDR 6 /* Card is in 8 bit ddr mode */ #define EXT_CSD_HS_TIMING 185 /* R/W */ #define EXT_CSD_CARD_TYPE 196 /* RO */ #define EXT_CSD_CARD_TYPE_26 (1<<0) /* Card can run at 26MHz */ #define EXT_CSD_CARD_TYPE_52 (1<<1) /* Card can run at 52MHz */ #define EXT_CSD_CARD_TYPE_DDR_52 (2<<1) /* Card can run at DDR 52MHz */ #define EXT_CSD_REV 192 /* RO */ #define EXT_CSD_SEC_CNT 212 /* RO, 4 bytes */ #define EXT_CSD_BOOT_SIZE_MULT 226 /* RO, 1 bytes */ #define EXT_CSD_BOOT_INFO 228 /* RO, 1 bytes */