On 2021-01-21 02:04, Leizhen (ThunderTown) wrote:
On 2021/1/20 23:02, Robin Murphy wrote:
On 2021-01-19 01:59, Zhen Lei wrote:
This reverts commit 52f3fab0067d6fa9e99c1b7f63265dd48ca76046.
This problem has been fixed by another patch. The original method had side
effects, it was not mapped to the user-specified resource size. The code
will become more complex when ECMDQ is supported later.
FWIW I don't think that's a significant issue either way - there could be any
number of imp-def pages between SMMU page 0 and the ECMDQ control pages, so it
will still be logical to map them as another separate thing anyway.
Yes, so now I'm thinking of preserving the SMMUv3 resources and eliminating the
imp-def area. Then use another devm_ioremap() to cover the entire resource，assign
it to smmu->base.
Otherwise, a base pointer needs to be defined for each separated register
space，or call a function to convert each time.
But we'll almost certainly want to maintain a pointer to start of the
ECMDQ control page block anyway, since that's not fixed relative to
smmu->base. Therefore what's the harm in handling that via a dedicated
mapping, once we've determined that we *do* intend to use ECMDQs?
Otherwise we end up with in the complicated dance of trying to map
"everything" up-front in order to be able to read the ID registers to
determine what the actual extent of "everything" is supposed to be.
(also this reminds me that I was going to remove arm_smmu_page1_fixup()
entirely - I'd totally forgotten about that...)
Robin.
Signed-off-by: Zhen Lei <thunder.leiz...@huawei.com>
---
drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.c | 32
++++-------------------------
drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.h | 3 ---
2 files changed, 4 insertions(+), 31 deletions(-)
diff --git a/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.c
b/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.c
index 8ca7415d785d9bf..477f473842e5272 100644
--- a/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.c
+++ b/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.c
@@ -91,8 +91,9 @@ struct arm_smmu_option_prop {
static inline void __iomem *arm_smmu_page1_fixup(unsigned long offset,
struct arm_smmu_device *smmu)
{
- if (offset > SZ_64K)
- return smmu->page1 + offset - SZ_64K;
+ if ((offset > SZ_64K) &&
+ (smmu->options & ARM_SMMU_OPT_PAGE0_REGS_ONLY))
+ offset -= SZ_64K;
return smmu->base + offset;
}
@@ -3486,18 +3487,6 @@ static int arm_smmu_set_bus_ops(struct iommu_ops *ops)
return err;
}
-static void __iomem *arm_smmu_ioremap(struct device *dev, resource_size_t
start,
- resource_size_t size)
-{
- struct resource res = {
- .flags = IORESOURCE_MEM,
- .start = start,
- .end = start + size - 1,
- };
-
- return devm_ioremap_resource(dev, &res);
-}
-
static int arm_smmu_device_probe(struct platform_device *pdev)
{
int irq, ret;
@@ -3533,23 +3522,10 @@ static int arm_smmu_device_probe(struct platform_device
*pdev)
}
ioaddr = res->start;
- /*
- * Don't map the IMPLEMENTATION DEFINED regions, since they may contain
- * the PMCG registers which are reserved by the PMU driver.
- */
- smmu->base = arm_smmu_ioremap(dev, ioaddr, ARM_SMMU_REG_SZ);
+ smmu->base = devm_ioremap_resource(dev, res);
if (IS_ERR(smmu->base))
return PTR_ERR(smmu->base);
- if (arm_smmu_resource_size(smmu) > SZ_64K) {
- smmu->page1 = arm_smmu_ioremap(dev, ioaddr + SZ_64K,
- ARM_SMMU_REG_SZ);
- if (IS_ERR(smmu->page1))
- return PTR_ERR(smmu->page1);
- } else {
- smmu->page1 = smmu->base;
- }
-
/* Interrupt lines */
irq = platform_get_irq_byname_optional(pdev, "combined");
diff --git a/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.h
b/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.h
index 96c2e9565e00282..0c3090c60840c22 100644
--- a/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.h
+++ b/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.h
@@ -152,8 +152,6 @@
#define ARM_SMMU_PRIQ_IRQ_CFG1 0xd8
#define ARM_SMMU_PRIQ_IRQ_CFG2 0xdc
-#define ARM_SMMU_REG_SZ 0xe00
-
/* Common MSI config fields */
#define MSI_CFG0_ADDR_MASK GENMASK_ULL(51, 2)
#define MSI_CFG2_SH GENMASK(5, 4)
@@ -584,7 +582,6 @@ struct arm_smmu_strtab_cfg {
struct arm_smmu_device {
struct device *dev;
void __iomem *base;
- void __iomem *page1;
#define ARM_SMMU_FEAT_2_LVL_STRTAB (1 << 0)
#define ARM_SMMU_FEAT_2_LVL_CDTAB (1 << 1)
.
