While SDHCI claims to support 64-bit DMA on MSM8916 it does not seem to
be properly functional. It is not immediately obvious because SDHCI is
usually used with IOMMU bypassed on this SoC, and all physical memory
has 32-bit addresses. But when trying to enable the IOMMU it quickly
fails with an error such as the following:
arm-smmu 1e00000.iommu: Unhandled context fault:
fsr=0x402, iova=0xfffff200, fsynr=0xe0000, cbfrsynra=0x140, cb=3
mmc1: ADMA error: 0x02000000
mmc1: sdhci: ============ SDHCI REGISTER DUMP ===========
mmc1: sdhci: Sys addr: 0x00000000 | Version: 0x00002e02
mmc1: sdhci: Blk size: 0x00000008 | Blk cnt: 0x00000000
mmc1: sdhci: Argument: 0x00000000 | Trn mode: 0x00000013
mmc1: sdhci: Present: 0x03f80206 | Host ctl: 0x00000019
mmc1: sdhci: Power: 0x0000000f | Blk gap: 0x00000000
mmc1: sdhci: Wake-up: 0x00000000 | Clock: 0x00000007
mmc1: sdhci: Timeout: 0x0000000a | Int stat: 0x00000001
mmc1: sdhci: Int enab: 0x03ff900b | Sig enab: 0x03ff100b
mmc1: sdhci: ACmd stat: 0x00000000 | Slot int: 0x00000000
mmc1: sdhci: Caps: 0x322dc8b2 | Caps_1: 0x00008007
mmc1: sdhci: Cmd: 0x0000333a | Max curr: 0x00000000
mmc1: sdhci: Resp[0]: 0x00000920 | Resp[1]: 0x5b590000
mmc1: sdhci: Resp[2]: 0xe6487f80 | Resp[3]: 0x0a404094
mmc1: sdhci: Host ctl2: 0x00000008
mmc1: sdhci: ADMA Err: 0x00000001 | ADMA Ptr: 0x0000000ffffff224
mmc1: sdhci_msm: ----------- VENDOR REGISTER DUMP -----------
mmc1: sdhci_msm: DLL sts: 0x00000000 | DLL cfg: 0x60006400 | DLL cfg2: 0x00000000
mmc1: sdhci_msm: DLL cfg3: 0x00000000 | DLL usr ctl: 0x00000000 | DDR cfg: 0x00000000
mmc1: sdhci_msm: Vndr func: 0x00018a9c | Vndr func2 : 0xf88018a8 Vndr func3: 0x00000000
mmc1: sdhci: ============================================
mmc1: sdhci: fffffffff200: DMA 0x0000ffffffffe100, LEN 0x0008, Attr=0x21
mmc1: sdhci: fffffffff20c: DMA 0x0000000000000000, LEN 0x0000, Attr=0x03
Looking closely it's obvious that only the 32-bit part of the address
(0xfffff200) arrives at the SMMU, the higher 16-bit (0xffff...) get
lost somewhere. This might not be a limitation of the SDHCI itself but
perhaps the bus/interconnect it is connected to, or even the connection
to the SMMU.
Work around this by setting SDHCI_QUIRK2_BROKEN_64_BIT_DMA to avoid
using 64-bit addresses.
Signed-off-by: Stephan Gerhold <stephan@gerhold.net>
Acked-by: Adrian Hunter <adrian.hunter@intel.com>
Cc: stable@vger.kernel.org
Link: https://lore.kernel.org/r/20230518-msm8916-64bit-v1-1-5694b0f35211@gerhold.net
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
e6f9e590b7