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author | Douglas Anderson <dianders@chromium.org> | 2023-06-16 18:14:40 +0300 |
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committer | Bjorn Andersson <andersson@kernel.org> | 2023-06-22 22:20:12 +0300 |
commit | a54b7fa6b9ab6b4ecb7d9aba6b1a0ce1bcc961e3 (patch) | |
tree | 13097ed00f007c913b3a403d79af81098f8d3a09 | |
parent | 9a5f0b11e49e27f0a01a73c31d05df4a95bea3fa (diff) | |
download | linux-a54b7fa6b9ab6b4ecb7d9aba6b1a0ce1bcc961e3.tar.xz |
arm64: dts: qcom: sc7180: Mark SCM as dma-coherent for trogdor
Trogdor devices use firmware backed by TF-A instead of Qualcomm's
normal TZ. On TF-A we end up mapping memory as cacheable.
Specifically, you can see in Trogdor's TF-A code [1] in
qti_sip_mem_assign() that we call qti_mmap_add_dynamic_region() with
MT_RO_DATA. This translates down to MT_MEMORY instead of
MT_NON_CACHEABLE or MT_DEVICE. Apparently Qualcomm's normal TZ
implementation maps the memory as non-cacheable.
Let's add the "dma-coherent" attribute to the SCM for trogdor.
Adding "dma-coherent" like this fixes WiFi on sc7180-trogdor
devices. WiFi was broken as of commit 7bd6680b47fa ("Revert "Revert
"arm64: dma: Drop cache invalidation from
arch_dma_prep_coherent()"""). Specifically at bootup we'd get:
qcom_scm firmware:scm: Assign memory protection call failed -22
qcom_rmtfs_mem 94600000.memory: assign memory failed
qcom_rmtfs_mem: probe of 94600000.memory failed with error -22
From discussion on the mailing lists [2] and over IRC [3], it was
determined that we should always have been tagging the SCM as
dma-coherent on trogdor but that the old "invalidate" happened to make
things work most of the time. Tagging it properly like this is a much
more robust solution.
[1] https://chromium.googlesource.com/chromiumos/third_party/arm-trusted-firmware/+/refs/heads/firmware-trogdor-13577.B/plat/qti/common/src/qti_syscall.c
[2] https://lore.kernel.org/r/20230614165904.1.I279773c37e2c1ed8fbb622ca6d1397aea0023526@changeid
[3] https://oftc.irclog.whitequark.org/linux-msm/2023-06-15
Fixes: 7bd6680b47fa ("Revert "Revert "arm64: dma: Drop cache invalidation from arch_dma_prep_coherent()""")
Fixes: 7ec3e67307f8 ("arm64: dts: qcom: sc7180-trogdor: add initial trogdor and lazor dt")
Reviewed-by: Konrad Dybcio <konrad.dybcio@linaro.org>
Signed-off-by: Douglas Anderson <dianders@chromium.org>
Link: https://lore.kernel.org/r/20230616081440.v2.3.Ic62daa649b47b656b313551d646c4de9a7da4bd4@changeid
Signed-off-by: Bjorn Andersson <andersson@kernel.org>
-rw-r--r-- | arch/arm64/boot/dts/qcom/sc7180-trogdor.dtsi | 5 |
1 files changed, 5 insertions, 0 deletions
diff --git a/arch/arm64/boot/dts/qcom/sc7180-trogdor.dtsi b/arch/arm64/boot/dts/qcom/sc7180-trogdor.dtsi index ca6920de7ea8..1472e7f10831 100644 --- a/arch/arm64/boot/dts/qcom/sc7180-trogdor.dtsi +++ b/arch/arm64/boot/dts/qcom/sc7180-trogdor.dtsi @@ -892,6 +892,11 @@ hp_i2c: &i2c9 { qcom,spare-regs = <&tcsr_regs_2 0xb3e4>; }; +&scm { + /* TF-A firmware maps memory cached so mark dma-coherent to match. */ + dma-coherent; +}; + &sdhc_1 { status = "okay"; |