Reset is an activity rife with implementation-defined poking. Add a
corresponding hook, and use it to encapsulate the existing MMU-500
details.
Signed-off-by: Robin Murphy <robin.mur...@arm.com>
---
drivers/iommu/arm-smmu-impl.c | 49 +++++++++++++++++++++++++++++++++++
drivers/iommu/arm-smmu.c | 39 +++-------------------------
drivers/iommu/arm-smmu.h | 1 +
3 files changed, 54 insertions(+), 35 deletions(-)
diff --git a/drivers/iommu/arm-smmu-impl.c b/drivers/iommu/arm-smmu-impl.c
index 696417908793..4dc8b1c4befb 100644
--- a/drivers/iommu/arm-smmu-impl.c
+++ b/drivers/iommu/arm-smmu-impl.c
@@ -4,6 +4,7 @@
#define pr_fmt(fmt) "arm-smmu: " fmt
+#include <linux/bitfield.h>
#include <linux/of.h>
#include "arm-smmu.h"
@@ -67,6 +68,51 @@ const struct arm_smmu_impl cavium_impl = {
};
+#define ARM_MMU500_ACTLR_CPRE (1 << 1)
+
+#define ARM_MMU500_ACR_CACHE_LOCK (1 << 26)
+#define ARM_MMU500_ACR_S2CRB_TLBEN (1 << 10)
+#define ARM_MMU500_ACR_SMTNMB_TLBEN (1 << 8)
+
+static int arm_mmu500_reset(struct arm_smmu_device *smmu)
+{
+ u32 reg, major;
+ int i;
+ /*
+ * On MMU-500 r2p0 onwards we need to clear ACR.CACHE_LOCK before
+ * writes to the context bank ACTLRs will stick. And we just hope that
+ * Secure has also cleared SACR.CACHE_LOCK for this to take effect...
+ */
+ reg = arm_smmu_gr0_read(smmu, ARM_SMMU_GR0_ID7);
+ major = FIELD_GET(ID7_MAJOR, reg);
+ reg = arm_smmu_gr0_read(smmu, ARM_SMMU_GR0_sACR);
+ if (major >= 2)
+ reg &= ~ARM_MMU500_ACR_CACHE_LOCK;
+ /*
+ * Allow unmatched Stream IDs to allocate bypass
+ * TLB entries for reduced latency.
+ */
+ reg |= ARM_MMU500_ACR_SMTNMB_TLBEN | ARM_MMU500_ACR_S2CRB_TLBEN;
+ arm_smmu_gr0_write(smmu, ARM_SMMU_GR0_sACR, reg);
+
+ /*
+ * Disable MMU-500's not-particularly-beneficial next-page
+ * prefetcher for the sake of errata #841119 and #826419.
+ */
+ for (i = 0; i < smmu->num_context_banks; ++i) {
+ reg = arm_smmu_cb_read(smmu, i, ARM_SMMU_CB_ACTLR);
+ reg &= ~ARM_MMU500_ACTLR_CPRE;
+ arm_smmu_cb_write(smmu, i, ARM_SMMU_CB_ACTLR, reg);
+ }
+
+ return 0;
+}
+
+const struct arm_smmu_impl arm_mmu500_impl = {
+ .reset = arm_mmu500_reset,
+};
+
+
struct arm_smmu_device *arm_smmu_impl_init(struct arm_smmu_device *smmu)
{
/*
@@ -76,6 +122,9 @@ struct arm_smmu_device *arm_smmu_impl_init(struct
arm_smmu_device *smmu)
* mutually-exclusive assignments.
*/
switch (smmu->model) {
+ case ARM_MMU500:
+ smmu->impl = &arm_mmu500_impl;
+ break;
case CAVIUM_SMMUV2:
smmu->impl = &cavium_impl;
break;
diff --git a/drivers/iommu/arm-smmu.c b/drivers/iommu/arm-smmu.c
index 362b6b5a28ee..fc98992d120d 100644
--- a/drivers/iommu/arm-smmu.c
+++ b/drivers/iommu/arm-smmu.c
@@ -54,12 +54,6 @@
*/
#define QCOM_DUMMY_VAL -1
-#define ARM_MMU500_ACTLR_CPRE (1 << 1)
-
-#define ARM_MMU500_ACR_CACHE_LOCK (1 << 26)
-#define ARM_MMU500_ACR_S2CRB_TLBEN (1 << 10)
-#define ARM_MMU500_ACR_SMTNMB_TLBEN (1 << 8)
-
#define TLB_LOOP_TIMEOUT 1000000 /* 1s! */
#define TLB_SPIN_COUNT 10
@@ -1574,7 +1568,7 @@ static struct iommu_ops arm_smmu_ops = {
static void arm_smmu_device_reset(struct arm_smmu_device *smmu)
{
int i;
- u32 reg, major;
+ u32 reg;
/* clear global FSR */
reg = arm_smmu_gr0_read(smmu, ARM_SMMU_GR0_sGFSR);
@@ -1587,38 +1581,10 @@ static void arm_smmu_device_reset(struct
arm_smmu_device *smmu)
for (i = 0; i < smmu->num_mapping_groups; ++i)
arm_smmu_write_sme(smmu, i);
- if (smmu->model == ARM_MMU500) {
- /*
- * Before clearing ARM_MMU500_ACTLR_CPRE, need to
- * clear CACHE_LOCK bit of ACR first. And, CACHE_LOCK
- * bit is only present in MMU-500r2 onwards.
- */
- reg = arm_smmu_gr0_read(smmu, ARM_SMMU_GR0_ID7);
- major = FIELD_GET(ID7_MAJOR, reg);
- reg = arm_smmu_gr0_read(smmu, ARM_SMMU_GR0_sACR);
- if (major >= 2)
- reg &= ~ARM_MMU500_ACR_CACHE_LOCK;
- /*
- * Allow unmatched Stream IDs to allocate bypass
- * TLB entries for reduced latency.
- */
- reg |= ARM_MMU500_ACR_SMTNMB_TLBEN | ARM_MMU500_ACR_S2CRB_TLBEN;
- arm_smmu_gr0_write(smmu, ARM_SMMU_GR0_sACR, reg);
- }
-
/* Make sure all context banks are disabled and clear CB_FSR */
for (i = 0; i < smmu->num_context_banks; ++i) {
arm_smmu_write_context_bank(smmu, i);
arm_smmu_cb_write(smmu, i, ARM_SMMU_CB_FSR, FSR_FAULT);
- /*
- * Disable MMU-500's not-particularly-beneficial next-page
- * prefetcher for the sake of errata #841119 and #826419.
- */
- if (smmu->model == ARM_MMU500) {
- reg = arm_smmu_cb_read(smmu, i, ARM_SMMU_CB_ACTLR);
- reg &= ~ARM_MMU500_ACTLR_CPRE;
- arm_smmu_cb_write(smmu, i, ARM_SMMU_CB_ACTLR, reg);
- }
}
/* Invalidate the TLB, just in case */
@@ -1652,6 +1618,9 @@ static void arm_smmu_device_reset(struct arm_smmu_device
*smmu)
if (smmu->features & ARM_SMMU_FEAT_EXIDS)
reg |= sCR0_EXIDENABLE;
+ if (smmu->impl && smmu->impl->reset)
+ smmu->impl->reset(smmu);
+
/* Push the button */
arm_smmu_tlb_sync_global(smmu);
arm_smmu_gr0_write(smmu, ARM_SMMU_GR0_sCR0, reg);
diff --git a/drivers/iommu/arm-smmu.h b/drivers/iommu/arm-smmu.h
index f4e90f33fce2..ddafe872a396 100644
--- a/drivers/iommu/arm-smmu.h
+++ b/drivers/iommu/arm-smmu.h
@@ -288,6 +288,7 @@ struct arm_smmu_impl {
void (*write_reg64)(struct arm_smmu_device *smmu, int page, int offset,
u64 val);
int (*cfg_probe)(struct arm_smmu_device *smmu);
+ int (*reset)(struct arm_smmu_device *smmu);
};
static inline void __iomem *arm_smmu_page(struct arm_smmu_device *smmu, int n)
--
2.21.0.dirty
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