Merging upstream version 6.1.85.

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 172 insertions, 0 deletions

diff --git a/drivers/iommu/intel/perfmon.c b/drivers/iommu/intel/perfmon.c
new file mode 100644
index 000000000..db5791a54
--- /dev/null
+++ b/drivers/iommu/intel/perfmon.c
@@ -0,0 +1,172 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * Support Intel IOMMU PerfMon
+ * Copyright(c) 2023 Intel Corporation.
+ */
+#define pr_fmt(fmt)	"DMAR: " fmt
+#define dev_fmt(fmt)	pr_fmt(fmt)
+
+#include <linux/dmar.h>
+#include "iommu.h"
+#include "perfmon.h"
+
+static inline void __iomem *
+get_perf_reg_address(struct intel_iommu *iommu, u32 offset)
+{
+	u32 off = dmar_readl(iommu->reg + offset);
+
+	return iommu->reg + off;
+}
+
+int alloc_iommu_pmu(struct intel_iommu *iommu)
+{
+	struct iommu_pmu *iommu_pmu;
+	int i, j, ret;
+	u64 perfcap;
+	u32 cap;
+
+	if (!ecap_pms(iommu->ecap))
+		return 0;
+
+	/* The IOMMU PMU requires the ECMD support as well */
+	if (!cap_ecmds(iommu->cap))
+		return -ENODEV;
+
+	perfcap = dmar_readq(iommu->reg + DMAR_PERFCAP_REG);
+	/* The performance monitoring is not supported. */
+	if (!perfcap)
+		return -ENODEV;
+
+	/* Sanity check for the number of the counters and event groups */
+	if (!pcap_num_cntr(perfcap) || !pcap_num_event_group(perfcap))
+		return -ENODEV;
+
+	/* The interrupt on overflow is required */
+	if (!pcap_interrupt(perfcap))
+		return -ENODEV;
+
+	iommu_pmu = kzalloc(sizeof(*iommu_pmu), GFP_KERNEL);
+	if (!iommu_pmu)
+		return -ENOMEM;
+
+	iommu_pmu->num_cntr = pcap_num_cntr(perfcap);
+	iommu_pmu->cntr_width = pcap_cntr_width(perfcap);
+	iommu_pmu->filter = pcap_filters_mask(perfcap);
+	iommu_pmu->cntr_stride = pcap_cntr_stride(perfcap);
+	iommu_pmu->num_eg = pcap_num_event_group(perfcap);
+
+	iommu_pmu->evcap = kcalloc(iommu_pmu->num_eg, sizeof(u64), GFP_KERNEL);
+	if (!iommu_pmu->evcap) {
+		ret = -ENOMEM;
+		goto free_pmu;
+	}
+
+	/* Parse event group capabilities */
+	for (i = 0; i < iommu_pmu->num_eg; i++) {
+		u64 pcap;
+
+		pcap = dmar_readq(iommu->reg + DMAR_PERFEVNTCAP_REG +
+				  i * IOMMU_PMU_CAP_REGS_STEP);
+		iommu_pmu->evcap[i] = pecap_es(pcap);
+	}
+
+	iommu_pmu->cntr_evcap = kcalloc(iommu_pmu->num_cntr, sizeof(u32 *), GFP_KERNEL);
+	if (!iommu_pmu->cntr_evcap) {
+		ret = -ENOMEM;
+		goto free_pmu_evcap;
+	}
+	for (i = 0; i < iommu_pmu->num_cntr; i++) {
+		iommu_pmu->cntr_evcap[i] = kcalloc(iommu_pmu->num_eg, sizeof(u32), GFP_KERNEL);
+		if (!iommu_pmu->cntr_evcap[i]) {
+			ret = -ENOMEM;
+			goto free_pmu_cntr_evcap;
+		}
+		/*
+		 * Set to the global capabilities, will adjust according
+		 * to per-counter capabilities later.
+		 */
+		for (j = 0; j < iommu_pmu->num_eg; j++)
+			iommu_pmu->cntr_evcap[i][j] = (u32)iommu_pmu->evcap[j];
+	}
+
+	iommu_pmu->cfg_reg = get_perf_reg_address(iommu, DMAR_PERFCFGOFF_REG);
+	iommu_pmu->cntr_reg = get_perf_reg_address(iommu, DMAR_PERFCNTROFF_REG);
+	iommu_pmu->overflow = get_perf_reg_address(iommu, DMAR_PERFOVFOFF_REG);
+
+	/*
+	 * Check per-counter capabilities. All counters should have the
+	 * same capabilities on Interrupt on Overflow Support and Counter
+	 * Width.
+	 */
+	for (i = 0; i < iommu_pmu->num_cntr; i++) {
+		cap = dmar_readl(iommu_pmu->cfg_reg +
+				 i * IOMMU_PMU_CFG_OFFSET +
+				 IOMMU_PMU_CFG_CNTRCAP_OFFSET);
+		if (!iommu_cntrcap_pcc(cap))
+			continue;
+
+		/*
+		 * It's possible that some counters have a different
+		 * capability because of e.g., HW bug. Check the corner
+		 * case here and simply drop those counters.
+		 */
+		if ((iommu_cntrcap_cw(cap) != iommu_pmu->cntr_width) ||
+		    !iommu_cntrcap_ios(cap)) {
+			iommu_pmu->num_cntr = i;
+			pr_warn("PMU counter capability inconsistent, counter number reduced to %d\n",
+				iommu_pmu->num_cntr);
+		}
+
+		/* Clear the pre-defined events group */
+		for (j = 0; j < iommu_pmu->num_eg; j++)
+			iommu_pmu->cntr_evcap[i][j] = 0;
+
+		/* Override with per-counter event capabilities */
+		for (j = 0; j < iommu_cntrcap_egcnt(cap); j++) {
+			cap = dmar_readl(iommu_pmu->cfg_reg + i * IOMMU_PMU_CFG_OFFSET +
+					 IOMMU_PMU_CFG_CNTREVCAP_OFFSET +
+					 (j * IOMMU_PMU_OFF_REGS_STEP));
+			iommu_pmu->cntr_evcap[i][iommu_event_group(cap)] = iommu_event_select(cap);
+			/*
+			 * Some events may only be supported by a specific counter.
+			 * Track them in the evcap as well.
+			 */
+			iommu_pmu->evcap[iommu_event_group(cap)] |= iommu_event_select(cap);
+		}
+	}
+
+	iommu_pmu->iommu = iommu;
+	iommu->pmu = iommu_pmu;
+
+	return 0;
+
+free_pmu_cntr_evcap:
+	for (i = 0; i < iommu_pmu->num_cntr; i++)
+		kfree(iommu_pmu->cntr_evcap[i]);
+	kfree(iommu_pmu->cntr_evcap);
+free_pmu_evcap:
+	kfree(iommu_pmu->evcap);
+free_pmu:
+	kfree(iommu_pmu);
+
+	return ret;
+}
+
+void free_iommu_pmu(struct intel_iommu *iommu)
+{
+	struct iommu_pmu *iommu_pmu = iommu->pmu;
+
+	if (!iommu_pmu)
+		return;
+
+	if (iommu_pmu->evcap) {
+		int i;
+
+		for (i = 0; i < iommu_pmu->num_cntr; i++)
+			kfree(iommu_pmu->cntr_evcap[i]);
+		kfree(iommu_pmu->cntr_evcap);
+	}
+	kfree(iommu_pmu->evcap);
+	kfree(iommu_pmu);
+	iommu->pmu = NULL;
+}