The capacity calculation for high-capacity SD cards (SDHC/SDXC/SDUC) used an incorrect bit shift (10 bits instead of 19 or 22), leading to severely underestimated storage capacities. - For SDHC/SDXC (CSD structure version 1), the capacity is defined as: `(C_SIZE + 1) * 512 KiB` (SD Physical Layer Spec v3.01, section 5.3.3). This requires a left shift by 19 bits (2^19 = 512 KiB). - For SDUC (CSD structure version 2), the capacity is: `(C_SIZE + 1) * 4096 KiB` (SD Physical Layer Spec v7.10, section 5.3.3), requiring a left shift by 22 bits (2^22 = 4096 KiB). Update the shifts to 19 and 22 bits for versions 1 and 2 respectively, ensuring accurate capacity reporting. This resolves issues where cards (e.g., 64GB) were incorrectly identified as 1-4GB. Signed-off-by: sooraj <sooraj20636@xxxxxxxxx> --- drivers/mmc/core/sd.c | 6 +++++- 1 file changed, 5 insertions(+), 1 deletion(-) diff --git a/drivers/mmc/core/sd.c b/drivers/mmc/core/sd.c index cc757b850e79..b60de859e978 100644 --- a/drivers/mmc/core/sd.c +++ b/drivers/mmc/core/sd.c @@ -172,7 +172,11 @@ static int mmc_decode_csd(struct mmc_card *card, bool is_sduc) else if (csd->c_size >= 0xFFFF) mmc_card_set_ext_capacity(card); - csd->capacity = (1 + (typeof(sector_t))m) << 10; + /* Correct the capacity calculation based on CSD structure version */ + if (csd_struct == 1) + csd->capacity = (1 + (typeof(sector_t))m) << 19; /* SDHC/SDXC: (C_SIZE + 1) * 512KB */ + else + csd->capacity = (1 + (typeof(sector_t))m) << 22; /* SDUC: (C_SIZE + 1) * 4096KB */ csd->read_blkbits = 9; csd->read_partial = 0; -- 2.45.2
