On 15/11/2021 16:54, Ulf Hansson wrote:
> On Mon, 15 Nov 2021 at 09:24, Adrian Hunter <adrian.hunter@xxxxxxxxx> wrote:
>>
>> The block layer forces a minimum segment size of PAGE_SIZE, so a segment
>> can be too big for the ADMA table, if PAGE_SIZE >= 64KiB. Fix by writing
>> multiple descriptors, noting that the ADMA table is sized for 4KiB chunks
>> anyway, so it will be big enough.
>>
>> Reported-and-tested-by: Bough Chen <haibo.chen@xxxxxxx>
>> Signed-off-by: Adrian Hunter <adrian.hunter@xxxxxxxxx>
>
> Applied for next, thanks!
>
> Should we perhaps tag this for stable and/or queue it as a fix for v5.16?
Could do. I thought I would leave it up to Haibo Chen.
>
> Kind regards
> Uffe
>
>
>
>> ---
>> drivers/mmc/host/sdhci.c | 21 ++++++++++++++++++---
>> drivers/mmc/host/sdhci.h | 4 +++-
>> 2 files changed, 21 insertions(+), 4 deletions(-)
>>
>> diff --git a/drivers/mmc/host/sdhci.c b/drivers/mmc/host/sdhci.c
>> index 269c86569402..07c6da1f2f0f 100644
>> --- a/drivers/mmc/host/sdhci.c
>> +++ b/drivers/mmc/host/sdhci.c
>> @@ -771,7 +771,19 @@ static void sdhci_adma_table_pre(struct sdhci_host *host,
>> len -= offset;
>> }
>>
>> - BUG_ON(len > 65536);
>> + /*
>> + * The block layer forces a minimum segment size of PAGE_SIZE,
>> + * so 'len' can be too big here if PAGE_SIZE >= 64KiB. Write
>> + * multiple descriptors, noting that the ADMA table is sized
>> + * for 4KiB chunks anyway, so it will be big enough.
>> + */
>> + while (len > host->max_adma) {
>> + int n = 32 * 1024; /* 32KiB*/
>> +
>> + __sdhci_adma_write_desc(host, &desc, addr, n, ADMA2_TRAN_VALID);
>> + addr += n;
>> + len -= n;
>> + }
>>
>> /* tran, valid */
>> if (len)
>> @@ -3968,6 +3980,7 @@ struct sdhci_host *sdhci_alloc_host(struct device *dev,
>> * descriptor for each segment, plus 1 for a nop end descriptor.
>> */
>> host->adma_table_cnt = SDHCI_MAX_SEGS * 2 + 1;
>> + host->max_adma = 65536;
>>
>> host->max_timeout_count = 0xE;
>>
>> @@ -4633,10 +4646,12 @@ int sdhci_setup_host(struct sdhci_host *host)
>> * be larger than 64 KiB though.
>> */
>> if (host->flags & SDHCI_USE_ADMA) {
>> - if (host->quirks & SDHCI_QUIRK_BROKEN_ADMA_ZEROLEN_DESC)
>> + if (host->quirks & SDHCI_QUIRK_BROKEN_ADMA_ZEROLEN_DESC) {
>> + host->max_adma = 65532; /* 32-bit alignment */
>> mmc->max_seg_size = 65535;
>> - else
>> + } else {
>> mmc->max_seg_size = 65536;
>> + }
>> } else {
>> mmc->max_seg_size = mmc->max_req_size;
>> }
>> diff --git a/drivers/mmc/host/sdhci.h b/drivers/mmc/host/sdhci.h
>> index bb883553d3b4..d7929d725730 100644
>> --- a/drivers/mmc/host/sdhci.h
>> +++ b/drivers/mmc/host/sdhci.h
>> @@ -340,7 +340,8 @@ struct sdhci_adma2_64_desc {
>>
>> /*
>> * Maximum segments assuming a 512KiB maximum requisition size and a minimum
>> - * 4KiB page size.
>> + * 4KiB page size. Note this also allows enough for multiple descriptors in
>> + * case of PAGE_SIZE >= 64KiB.
>> */
>> #define SDHCI_MAX_SEGS 128
>>
>> @@ -543,6 +544,7 @@ struct sdhci_host {
>> unsigned int blocks; /* remaining PIO blocks */
>>
>> int sg_count; /* Mapped sg entries */
>> + int max_adma; /* Max. length in ADMA descriptor */
>>
>> void *adma_table; /* ADMA descriptor table */
>> void *align_buffer; /* Bounce buffer */
>> --
>> 2.25.1
>>
