On Thu, Mar 25, 2021 at 05:07:52PM +0000, Robin Murphy wrote: > On 2021-03-25 17:02, Bjorn Andersson wrote: > > On Thu 25 Mar 09:59 CDT 2021, Will Deacon wrote: > > > > > [+ Lorenzo] > > > > > > On Mon, Mar 01, 2021 at 03:40:21PM +0800, Shawn Guo wrote: > > > > Though qcom_adreno_smmu_impl is not used by ACPI boot right now, > > > > qcom_smmu_impl is already required at least to boot up Lenovo Flex 5G > > > > laptop. Let's check asl_compiler_id in IORT header to ensure we are > > > > running a QCOM SMMU and create qcom_smmu_impl for it. > > > > > > > > !np is used to check ACPI boot, because fwnode of SMMU device is > > > > a static allocation and thus has_acpi_companion() doesn't work here. > > > > > > > > Signed-off-by: Shawn Guo <shawn.guo@xxxxxxxxxx> > > > > --- > > > > drivers/iommu/arm/arm-smmu/arm-smmu-qcom.c | 33 ++++++++++++++++++++++ > > > > 1 file changed, 33 insertions(+) > > > > > > I don't know what a "asl_compiler_id" is, but it doesn't sound like it > > > has an awful lot to do with the SMMU. > > > > > > > I would prefer that we somehow relate this to the particular board, > > rather than all Qualcomm-related ACPI tables. E.g. by relying on the > > SMMU devices having a _HID of QCOM0409. > > > > Shawn, any reason for this wouldn't be possible? > > To do something broadly similar to identify HiSilicon's SMMU PMCG > implementation, we use acpi_match_platform_list() - could we do the same for > this? Thanks for the suggestion, Robin! Yes, acpi_platform_list is useful for our problem as well. But we will need multiple entries even for a single Snapdragon SoC. For example, both Lenovo Flex 5G and Microsoft Surface Pro X are powered by Snapdragon SC8180X, but their IORT tables have different fields that acpi_match_platform_list() is looking at. If this is not a problem, yeah, acpi_platform_list is a better way out, and I will start updating the patch. Shawn * Lenovo Flex 5G [000h 0000 4] Signature : "IORT" [IO Remapping Table] [004h 0004 4] Table Length : 00001943 [008h 0008 1] Revision : 00 [009h 0009 1] Checksum : DA [00Ah 0010 6] Oem ID : "LENOVO" [010h 0016 8] Oem Table ID : "CB-01 " [018h 0024 4] Oem Revision : 00008180 [01Ch 0028 4] Asl Compiler ID : "QCOM" [020h 0032 4] Asl Compiler Revision : 00000001 * Microsoft Surface Pro X [000h 0000 4] Signature : "IORT" [IO Remapping Table] [004h 0004 4] Table Length : 0000169C [008h 0008 1] Revision : 00 [009h 0009 1] Checksum : 3A [00Ah 0010 6] Oem ID : "QCOM " [010h 0016 8] Oem Table ID : "QCOMEDK2" [018h 0024 4] Oem Revision : 00008180 [01Ch 0028 4] Asl Compiler ID : "QCOM" [020h 0032 4] Asl Compiler Revision : 00000001
