iommu/amd: Detect and initialize guest vAPIC log

This patch adds support to detect and initialize IOMMU Guest vAPIC log
(GALOG). By default, it also enable GALog interrupt to notify IOMMU driver
when GA Log entry is created.
Signed-off-by: Suravee Suthikulpanit <suravee.suthikulpanit@amd.com>
Signed-off-by: Joerg Roedel <jroedel@suse.de>

drivers/iommu/amd_iommu_init.c

@@ -84,6 +84,7 @@
 #define ACPI_DEVFLAG_LINT1              0x80
 #define ACPI_DEVFLAG_ATSDIS             0x10000000
 
+#define LOOP_TIMEOUT	100000
 /*
  * ACPI table definitions
  *
@@ -388,6 +389,10 @@ static void iommu_disable(struct amd_iommu *iommu)
 	iommu_feature_disable(iommu, CONTROL_EVT_INT_EN);
 	iommu_feature_disable(iommu, CONTROL_EVT_LOG_EN);
 
+	/* Disable IOMMU GA_LOG */
+	iommu_feature_disable(iommu, CONTROL_GALOG_EN);
+	iommu_feature_disable(iommu, CONTROL_GAINT_EN);
+
 	/* Disable IOMMU hardware itself */
 	iommu_feature_disable(iommu, CONTROL_IOMMU_EN);
 }
@@ -673,6 +678,99 @@ static void __init free_ppr_log(struct amd_iommu *iommu)
 	free_pages((unsigned long)iommu->ppr_log, get_order(PPR_LOG_SIZE));
 }
 
+static void free_ga_log(struct amd_iommu *iommu)
+{
+#ifdef CONFIG_IRQ_REMAP
+	if (iommu->ga_log)
+		free_pages((unsigned long)iommu->ga_log,
+			    get_order(GA_LOG_SIZE));
+	if (iommu->ga_log_tail)
+		free_pages((unsigned long)iommu->ga_log_tail,
+			    get_order(8));
+#endif
+}
+
+static int iommu_ga_log_enable(struct amd_iommu *iommu)
+{
+#ifdef CONFIG_IRQ_REMAP
+	u32 status, i;
+
+	if (!iommu->ga_log)
+		return -EINVAL;
+
+	status = readl(iommu->mmio_base + MMIO_STATUS_OFFSET);
+
+	/* Check if already running */
+	if (status & (MMIO_STATUS_GALOG_RUN_MASK))
+		return 0;
+
+	iommu_feature_enable(iommu, CONTROL_GAINT_EN);
+	iommu_feature_enable(iommu, CONTROL_GALOG_EN);
+
+	for (i = 0; i < LOOP_TIMEOUT; ++i) {
+		status = readl(iommu->mmio_base + MMIO_STATUS_OFFSET);
+		if (status & (MMIO_STATUS_GALOG_RUN_MASK))
+			break;
+	}
+
+	if (i >= LOOP_TIMEOUT)
+		return -EINVAL;
+#endif /* CONFIG_IRQ_REMAP */
+	return 0;
+}
+
+#ifdef CONFIG_IRQ_REMAP
+static int iommu_init_ga_log(struct amd_iommu *iommu)
+{
+	u64 entry;
+
+	if (!AMD_IOMMU_GUEST_IR_VAPIC(amd_iommu_guest_ir))
+		return 0;
+
+	iommu->ga_log = (u8 *)__get_free_pages(GFP_KERNEL | __GFP_ZERO,
+					get_order(GA_LOG_SIZE));
+	if (!iommu->ga_log)
+		goto err_out;
+
+	iommu->ga_log_tail = (u8 *)__get_free_pages(GFP_KERNEL | __GFP_ZERO,
+					get_order(8));
+	if (!iommu->ga_log_tail)
+		goto err_out;
+
+	entry = (u64)virt_to_phys(iommu->ga_log) | GA_LOG_SIZE_512;
+	memcpy_toio(iommu->mmio_base + MMIO_GA_LOG_BASE_OFFSET,
+		    &entry, sizeof(entry));
+	entry = ((u64)virt_to_phys(iommu->ga_log) & 0xFFFFFFFFFFFFFULL) & ~7ULL;
+	memcpy_toio(iommu->mmio_base + MMIO_GA_LOG_TAIL_OFFSET,
+		    &entry, sizeof(entry));
+	writel(0x00, iommu->mmio_base + MMIO_GA_HEAD_OFFSET);
+	writel(0x00, iommu->mmio_base + MMIO_GA_TAIL_OFFSET);
+
+	return 0;
+err_out:
+	free_ga_log(iommu);
+	return -EINVAL;
+}
+#endif /* CONFIG_IRQ_REMAP */
+
+static int iommu_init_ga(struct amd_iommu *iommu)
+{
+	int ret = 0;
+
+#ifdef CONFIG_IRQ_REMAP
+	/* Note: We have already checked GASup from IVRS table.
+	 *       Now, we need to make sure that GAMSup is set.
+	 */
+	if (AMD_IOMMU_GUEST_IR_VAPIC(amd_iommu_guest_ir) &&
+	    !iommu_feature(iommu, FEATURE_GAM_VAPIC))
+		amd_iommu_guest_ir = AMD_IOMMU_GUEST_IR_LEGACY_GA;
+
+	ret = iommu_init_ga_log(iommu);
+#endif /* CONFIG_IRQ_REMAP */
+
+	return ret;
+}
+
 static void iommu_enable_gt(struct amd_iommu *iommu)
 {
 	if (!iommu_feature(iommu, FEATURE_GT))
@@ -1146,6 +1244,7 @@ static void __init free_iommu_one(struct amd_iommu *iommu)
 	free_command_buffer(iommu);
 	free_event_buffer(iommu);
 	free_ppr_log(iommu);
+	free_ga_log(iommu);
 	iommu_unmap_mmio_space(iommu);
 }
 
@@ -1438,6 +1537,7 @@ static int iommu_init_pci(struct amd_iommu *iommu)
 {
 	int cap_ptr = iommu->cap_ptr;
 	u32 range, misc, low, high;
+	int ret;
 
 	iommu->dev = pci_get_bus_and_slot(PCI_BUS_NUM(iommu->devid),
 					  iommu->devid & 0xff);
@@ -1494,13 +1594,9 @@ static int iommu_init_pci(struct amd_iommu *iommu)
 	if (iommu_feature(iommu, FEATURE_PPR) && alloc_ppr_log(iommu))
 		return -ENOMEM;
 
-	/* Note: We have already checked GASup from IVRS table.
-	 *       Now, we need to make sure that GAMSup is set.
-	 */
-	if (AMD_IOMMU_GUEST_IR_VAPIC(amd_iommu_guest_ir) &&
-	    !iommu_feature(iommu, FEATURE_GAM_VAPIC))
-		amd_iommu_guest_ir = AMD_IOMMU_GUEST_IR_LEGACY_GA;
-
+	ret = iommu_init_ga(iommu);
+	if (ret)
+		return ret;
 
 	if (iommu->cap & (1UL << IOMMU_CAP_NPCACHE))
 		amd_iommu_np_cache = true;
@@ -1667,6 +1763,8 @@ static int iommu_init_msi(struct amd_iommu *iommu)
 	if (iommu->ppr_log != NULL)
 		iommu_feature_enable(iommu, CONTROL_PPFINT_EN);
 
+	iommu_ga_log_enable(iommu);
+
 	return 0;
 }
 

drivers/iommu/amd_iommu_types.h

@@ -70,6 +70,8 @@
 #define MMIO_EXCL_LIMIT_OFFSET  0x0028
 #define MMIO_EXT_FEATURES	0x0030
 #define MMIO_PPR_LOG_OFFSET	0x0038
+#define MMIO_GA_LOG_BASE_OFFSET	0x00e0
+#define MMIO_GA_LOG_TAIL_OFFSET	0x00e8
 #define MMIO_CMD_HEAD_OFFSET	0x2000
 #define MMIO_CMD_TAIL_OFFSET	0x2008
 #define MMIO_EVT_HEAD_OFFSET	0x2010
@@ -77,6 +79,8 @@
 #define MMIO_STATUS_OFFSET	0x2020
 #define MMIO_PPR_HEAD_OFFSET	0x2030
 #define MMIO_PPR_TAIL_OFFSET	0x2038
+#define MMIO_GA_HEAD_OFFSET	0x2040
+#define MMIO_GA_TAIL_OFFSET	0x2048
 #define MMIO_CNTR_CONF_OFFSET	0x4000
 #define MMIO_CNTR_REG_OFFSET	0x40000
 #define MMIO_REG_END_OFFSET	0x80000
@@ -112,6 +116,9 @@
 #define MMIO_STATUS_EVT_INT_MASK	(1 << 1)
 #define MMIO_STATUS_COM_WAIT_INT_MASK	(1 << 2)
 #define MMIO_STATUS_PPR_INT_MASK	(1 << 6)
+#define MMIO_STATUS_GALOG_RUN_MASK	(1 << 8)
+#define MMIO_STATUS_GALOG_OVERFLOW_MASK	(1 << 9)
+#define MMIO_STATUS_GALOG_INT_MASK	(1 << 10)
 
 /* event logging constants */
 #define EVENT_ENTRY_SIZE	0x10
@@ -150,6 +157,8 @@
 #define CONTROL_GT_EN           0x10ULL
 #define CONTROL_GA_EN           0x11ULL
 #define CONTROL_GAM_EN          0x19ULL
+#define CONTROL_GALOG_EN        0x1CULL
+#define CONTROL_GAINT_EN        0x1DULL
 
 #define CTRL_INV_TO_MASK	(7 << CONTROL_INV_TIMEOUT)
 #define CTRL_INV_TO_NONE	0
@@ -228,6 +237,19 @@
 
 #define PPR_REQ_FAULT		0x01
 
+/* Constants for GA Log handling */
+#define GA_LOG_ENTRIES		512
+#define GA_LOG_SIZE_SHIFT	56
+#define GA_LOG_SIZE_512		(0x8ULL << GA_LOG_SIZE_SHIFT)
+#define GA_ENTRY_SIZE		8
+#define GA_LOG_SIZE		(GA_ENTRY_SIZE * GA_LOG_ENTRIES)
+
+#define GA_TAG(x)		(u32)(x & 0xffffffffULL)
+#define GA_DEVID(x)		(u16)(((x) >> 32) & 0xffffULL)
+#define GA_REQ_TYPE(x)		(((x) >> 60) & 0xfULL)
+
+#define GA_GUEST_NR		0x1
+
 #define PAGE_MODE_NONE    0x00
 #define PAGE_MODE_1_LEVEL 0x01
 #define PAGE_MODE_2_LEVEL 0x02
@@ -501,6 +523,12 @@ struct amd_iommu {
 	/* Base of the PPR log, if present */
 	u8 *ppr_log;
 
+	/* Base of the GA log, if present */
+	u8 *ga_log;
+
+	/* Tail of the GA log, if present */
+	u8 *ga_log_tail;
+
 	/* true if interrupts for this IOMMU are already enabled */
 	bool int_enabled;