On Sat, Jan 30, 2021 at 03:14:13PM +0800, Zhen Lei wrote: > According to the SMMUv3 specification: > Each PMCG counter group is represented by one 4KB page (Page 0) with one > optional additional 4KB page (Page 1), both of which are at IMPLEMENTATION > DEFINED base addresses. > > This means that the PMCG register spaces may be within the 64KB pages of > the SMMUv3 register space. When both the SMMU and PMCG drivers reserve > their own resources, a resource conflict occurs. > > To avoid this conflict, don't reserve the PMCG regions. > > Suggested-by: Robin Murphy <robin.mur...@arm.com> > Signed-off-by: Zhen Lei <thunder.leiz...@huawei.com> > --- > drivers/perf/arm_smmuv3_pmu.c | 25 +++++++++++++++++++------ > 1 file changed, 19 insertions(+), 6 deletions(-) > > diff --git a/drivers/perf/arm_smmuv3_pmu.c b/drivers/perf/arm_smmuv3_pmu.c > index 74474bb322c3f26..5e894f957c7b935 100644 > --- a/drivers/perf/arm_smmuv3_pmu.c > +++ b/drivers/perf/arm_smmuv3_pmu.c > @@ -793,17 +793,30 @@ static int smmu_pmu_probe(struct platform_device *pdev) > .capabilities = PERF_PMU_CAP_NO_EXCLUDE, > }; > > - smmu_pmu->reg_base = devm_platform_get_and_ioremap_resource(pdev, 0, > &res_0); > - if (IS_ERR(smmu_pmu->reg_base)) > - return PTR_ERR(smmu_pmu->reg_base); > + /* > + * The register spaces of the PMCG may be in the register space of > + * other devices. For example, SMMU. Therefore, the PMCG resources are > + * not reserved to avoid resource conflicts with other drivers. > + */ > + res_0 = platform_get_resource(pdev, IORESOURCE_MEM, 0); > + if (!res_0) > + return ERR_PTR(-EINVAL);
I tried to apply this, but you've got your return type in a muddle: @@ @@ +drivers/perf/arm_smmuv3_pmu.c: In function ‘smmu_pmu_probe’: +drivers/perf/arm_smmuv3_pmu.c:803:10: warning: returning ‘void *’ from a function with return type ‘int’ makes integer from pointer without a cast [-Wint-conversion] + 803 | return ERR_PTR(-EINVAL); + | ^~~~~~~~~~~~~~~~ +drivers/perf/arm_smmuv3_pmu.c:803:31: warning: incorrect type in return expression (different base types) [sparse] +drivers/perf/arm_smmuv3_pmu.c:803:31: expected int [sparse] +drivers/perf/arm_smmuv3_pmu.c:803:31: got void * [sparse] +drivers/perf/arm_smmuv3_pmu.c:806:10: warning: returning ‘void *’ from a function with return type ‘int’ makes integer from pointer without a cast [-Wint-conversion] + 806 | return ERR_PTR(-ENOMEM); + | ^~~~~~~~~~~~~~~~ +drivers/perf/arm_smmuv3_pmu.c:806:31: warning: incorrect type in return expression (different base types) [sparse] +drivers/perf/arm_smmuv3_pmu.c:806:31: expected int [sparse] +drivers/perf/arm_smmuv3_pmu.c:806:31: got void * [sparse] +drivers/perf/arm_smmuv3_pmu.c:816:11: warning: returning ‘void *’ from a function with return type ‘int’ makes integer from pointer without a cast [-Wint-conversion] + 816 | return ERR_PTR(-EINVAL); + | ^~~~~~~~~~~~~~~~ +drivers/perf/arm_smmuv3_pmu.c:816:39: warning: incorrect type in return expression (different base types) [sparse] +drivers/perf/arm_smmuv3_pmu.c:816:39: expected int [sparse] +drivers/perf/arm_smmuv3_pmu.c:816:39: got void * [sparse] +drivers/perf/arm_smmuv3_pmu.c:819:11: warning: returning ‘void *’ from a function with return type ‘int’ makes integer from pointer without a cast [-Wint-conversion] + 819 | return ERR_PTR(-ENOMEM); + | ^~~~~~~~~~~~~~~~ +drivers/perf/arm_smmuv3_pmu.c:819:39: warning: incorrect type in return expression (different base types) [sparse] +drivers/perf/arm_smmuv3_pmu.c:819:39: expected int [sparse] +drivers/perf/arm_smmuv3_pmu.c:819:39: got void * [sparse] Will
