[PATCH 2/3] AMD IOMMUv2 PC resource management hooks
From: Steven L. Kinney
Date: Mon Jan 21 2013 - 15:21:40 EST
From: "Steven L. Kinney" <steven.kinney@xxxxxxx>
Add functionality to check the availability of the AMD IOMMUv2 Performance
Counters and export this functionality to other core drivers, such as in this
case, a perf IOMMUv2 PMU. This feature is not bound to any specific AMD
family/model other than the presence of the IOMMUv2 with PC enabled.
The IOMMUv2 PC support static counting only at this time.
Signed-off-by: Steven L. Kinney <steven.kinney@xxxxxxx>
---
drivers/iommu/Kconfig | 10 ++++
drivers/iommu/amd_iommu_init.c | 99 +++++++++++++++++++++++++++++++++++++++
drivers/iommu/amd_iommu_types.h | 12 +++++
3 files changed, 121 insertions(+)
diff --git a/drivers/iommu/Kconfig b/drivers/iommu/Kconfig
index e39f9db..4a941dd 100644
--- a/drivers/iommu/Kconfig
+++ b/drivers/iommu/Kconfig
@@ -73,6 +73,16 @@ config AMD_IOMMU_V2
hardware. Select this option if you want to use devices that support
the PCI PRI and PASID interface.
+# AMD IOMMUv2 Performance Counter support
+config AMD_IOMMU_V2_PC
+ bool "AMD IOMMUv2 Performance Counter (EXPERIMENTAL)"
+ depends on AMD_IOMMU_V2
+ ---help---
+ This option enables support for AMD IOMMUv2 Performance Counters.
+ Select this option if you want to enable IOMMUv2 Performance
+ Counter support.
+ If unsure, say N.
+
# Intel IOMMU support
config DMAR_TABLE
bool
diff --git a/drivers/iommu/amd_iommu_init.c b/drivers/iommu/amd_iommu_init.c
index 81837b0..f38db14 100644
--- a/drivers/iommu/amd_iommu_init.c
+++ b/drivers/iommu/amd_iommu_init.c
@@ -154,6 +154,7 @@ bool amd_iommu_iotlb_sup __read_mostly = true;
u32 amd_iommu_max_pasids __read_mostly = ~0;
bool amd_iommu_v2_present __read_mostly;
+bool amd_iommu_v2_pc_present __read_mostly;
bool amd_iommu_force_isolation __read_mostly;
@@ -1145,6 +1146,21 @@ static int iommu_init_pci(struct amd_iommu *iommu)
if (iommu->cap & (1UL << IOMMU_CAP_NPCACHE))
amd_iommu_np_cache = true;
+#ifdef CONFIG_AMD_IOMMU_V2_PC
+ if (iommu_feature(iommu, FEATURE_PC)) {
+ u32 val;
+ amd_iommu_v2_pc_present = true;
+ dev_printk(KERN_DEBUG, &iommu->dev->dev,
+ "AMD-Vi: IOMMUv2 perf counters supported\n");
+ val = readl(iommu->mmio_base + MMIO_CNTR_CONF_OFFSET);
+ iommu->max_banks = (u8) ((val >> 12) & 0x3f);
+ iommu->max_counters = (u8) ((val >> 7) & 0xf);
+ dev_printk(KERN_DEBUG, &iommu->dev->dev,
+ "AMD-Vi: %d counter banks, %d counters each\n",
+ iommu->max_banks, iommu->max_counters);
+ }
+#endif
+
if (is_rd890_iommu(iommu->dev)) {
int i, j;
@@ -2076,3 +2092,86 @@ bool amd_iommu_v2_supported(void)
return amd_iommu_v2_present;
}
EXPORT_SYMBOL(amd_iommu_v2_supported);
+
+#ifdef CONFIG_AMD_IOMMU_V2_PC
+/****************************************************************************
+ *
+ * IOMMUv2 EFR Performance Counter support functionality. This code allows
+ * access to the IOMMUv2 PC functionality.
+ *
+ ****************************************************************************/
+
+u8 amd_iommu_v2_get_max_pc_banks(u16 devid)
+{
+ struct amd_iommu *iommu;
+
+ /* locate the iommu governing the devid */
+ iommu = amd_iommu_rlookup_table[devid];
+
+ if (iommu)
+ return iommu->max_banks;
+
+ return -ENODEV;
+}
+EXPORT_SYMBOL(amd_iommu_v2_get_max_pc_banks);
+
+bool amd_iommu_v2_pc_supported(void)
+{
+ return amd_iommu_v2_pc_present;
+}
+EXPORT_SYMBOL(amd_iommu_v2_pc_supported);
+
+u8 amd_iommu_v2_get_max_pc_counters(u16 devid)
+{
+ struct amd_iommu *iommu;
+
+ /* locate the iommu governing the devid */
+ iommu = amd_iommu_rlookup_table[devid];
+
+ if (iommu)
+ return iommu->max_counters;
+
+ return -ENODEV;
+}
+EXPORT_SYMBOL(amd_iommu_v2_get_max_pc_counters);
+
+int amd_iommu_v2_get_set_pc_reg_val(u16 devid, u8 bank, u8 cntr, u8 fxn,
+ long long *value, bool is_write)
+{
+ struct amd_iommu *iommu;
+ u32 offset;
+ u32 max_offset_lim;
+
+ /* Make sure the IOMMUv2 PC resource is available */
+ if (!amd_iommu_v2_pc_present) {
+ pr_info("AMD IOMMUv2 - PC Not supported in amd_iommu_v2_get_set_pc_reg_val\n");
+ return -ENODEV;
+ }
+
+ /* locate the iommu associated with the device ID */
+ iommu = amd_iommu_rlookup_table[devid];
+ if (iommu == NULL)
+ return -ENODEV;
+
+ /* check for valid iommu pc register indexing */
+ if (fxn < 0 || fxn > 0x28 || (fxn & 7))
+ return -ENODEV;
+
+ offset = (u32)(((0x40|bank) << 12) | (cntr << 8) | fxn);
+
+ /* limit the offset to the hw defined mmio region aperture */
+ max_offset_lim = (u32)(((0x40|iommu->max_banks) << 12) |
+ (iommu->max_counters << 8) | 0x28);
+ if ((offset < IOMMU_V2_PC_REG_OFFSET) ||
+ (offset > max_offset_lim))
+ return -EINVAL;
+
+ if (is_write)
+ writel((u32)*value, iommu->mmio_base + offset);
+ else
+ *value = readl(iommu->mmio_base + offset);
+
+ return 0;
+}
+EXPORT_SYMBOL(amd_iommu_v2_get_set_pc_reg_val);
+#endif
diff --git a/drivers/iommu/amd_iommu_types.h b/drivers/iommu/amd_iommu_types.h
index e38ab43..fdf236b 100644
--- a/drivers/iommu/amd_iommu_types.h
+++ b/drivers/iommu/amd_iommu_types.h
@@ -38,7 +38,12 @@
#define RLOOKUP_TABLE_ENTRY_SIZE (sizeof(void *))
/* Length of the MMIO region for the AMD IOMMU */
+#ifdef CONFIG_AMD_IOMMU_V2_PC
+#define MMIO_REGION_LENGTH 0x80000
+#define IOMMU_V2_PC_REG_OFFSET 0x40000
+#else
#define MMIO_REGION_LENGTH 0x4000
+#endif
/* Capability offsets used by the driver */
#define MMIO_CAP_HDR_OFFSET 0x00
@@ -77,6 +82,7 @@
#define MMIO_STATUS_OFFSET 0x2020
#define MMIO_PPR_HEAD_OFFSET 0x2030
#define MMIO_PPR_TAIL_OFFSET 0x2038
+#define MMIO_CNTR_CONF_OFFSET 0x4000
/* Extended Feature Bits */
@@ -585,6 +591,12 @@ struct amd_iommu {
/* The l2 indirect registers */
u32 stored_l2[0x83];
+
+#ifdef CONFIG_AMD_IOMMU_V2_PC
+ /* The maximum PC banks and counters/bank (PCSup=1) */
+ u8 max_banks;
+ u8 max_counters;
+#endif
};
struct devid_map {
--
1.7.9.5
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