Hi Ulf,
On Thu, Aug 29, 2019 at 10:27 PM Ulf Hansson ulf.hansson@linaro.org wrote:
On Thu, 29 Aug 2019 at 14:05, Masahiro Yamada yamada.masahiro@socionext.com wrote:
On Thu, Aug 29, 2019 at 8:48 PM Ulf Hansson ulf.hansson@linaro.org wrote:
On Thu, 29 Aug 2019 at 12:49, Masahiro Yamada yamada.masahiro@socionext.com wrote:
The IP datasheet says this controller is compatible with SD Host Specification Version v4.00.
As it turned out, the ADMA of this IP does not work with 64-bit mode when it is in the Version 3.00 compatible mode; it understands the old 64-bit descriptor table (as defined in SDHCI v2), but the ADMA System Address Register (SDHCI_ADMA_ADDRESS) cannot point to the 64-bit address.
I noticed this issue only after commit bd2e75633c80 ("dma-contiguous: use fallback alloc_pages for single pages"). Prior to that commit, dma_set_mask_and_coherent() returned the dma address that fits in 32-bit range, at least for the default arm64 configuration (arch/arm64/configs/defconfig). Now the host->adma_addr exceeds the 32-bit limit, causing the real problem for the Socionext SoCs. (As a side-note, I was also able to reproduce the issue for older kernels by turning off CONFIG_DMA_CMA.)
Call sdhci_enable_v4_mode() to fix this.
I think it is better to back-port this, but only possible for v4.20+.
When this driver was merged (v4.10), the v4 mode support did not exist. It was added by commit b3f80b434f72 ("mmc: sdhci: Add sd host v4 mode") i.e. v4.20.
Cc: stable@vger.kernel.org # v4.20+ Signed-off-by: Masahiro Yamada yamada.masahiro@socionext.com
Applied for fixes, by adding below tag, thanks!
Fixes: b3f80b434f72 ("mmc: sdhci: Add sd host v4 mode")
This is not a bug commit.
Right, but it can't be applied before this commit, hence why I added it. Not sure that it matters, but I can remove the tag if you insists!?
I hesitate to add Fixes to the commit that did nothing wrong.
I added "Cc: stable@vger.kernel.org # v4.20+" so this is enough for the stable kernel maintainers.