drm/i915: enable error detection & state collection

This patch enables error detection by enabling several types of error
interrupts.  When an error interrupt is received, the interrupt
handler captures the error state; hopefully resulting in an accurate
set of error data (error type, active head pointer, etc.).  The new
record is then available from sysfs.  The current code will also dump
the error state to the system log.
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
Signed-off-by: Eric Anholt <eric@anholt.net>

drivers/gpu/drm/i915/i915_dma.c

@@ -1180,6 +1180,7 @@ int i915_driver_load(struct drm_device *dev, unsigned long flags)
 		pci_enable_msi(dev->pdev);
 
 	spin_lock_init(&dev_priv->user_irq_lock);
+	spin_lock_init(&dev_priv->error_lock);
 	dev_priv->user_irq_refcount = 0;
 
 	ret = drm_vblank_init(dev, I915_NUM_PIPE);

drivers/gpu/drm/i915/i915_drv.h

@@ -133,6 +133,22 @@ struct sdvo_device_mapping {
 	u8 initialized;
 };
 
+struct drm_i915_error_state {
+	u32 eir;
+	u32 pgtbl_er;
+	u32 pipeastat;
+	u32 pipebstat;
+	u32 ipeir;
+	u32 ipehr;
+	u32 instdone;
+	u32 acthd;
+	u32 instpm;
+	u32 instps;
+	u32 instdone1;
+	u32 seqno;
+	struct timeval time;
+};
+
 typedef struct drm_i915_private {
 	struct drm_device *dev;
 
@@ -209,6 +225,9 @@ typedef struct drm_i915_private {
 	int fence_reg_start; /* 4 if userland hasn't ioctl'd us yet */
 	int num_fence_regs; /* 8 on pre-965, 16 otherwise */
 
+	spinlock_t error_lock;
+	struct drm_i915_error_state *first_error;
+
 	/* Register state */
 	u8 saveLBB;
 	u32 saveDSPACNTR;

drivers/gpu/drm/i915/i915_gem_debugfs.c

@@ -323,6 +323,39 @@ static int i915_ringbuffer_info(struct seq_file *m, void *data)
 	return 0;
 }
 
+static int i915_error_state(struct seq_file *m, void *unused)
+{
+	struct drm_info_node *node = (struct drm_info_node *) m->private;
+	struct drm_device *dev = node->minor->dev;
+	drm_i915_private_t *dev_priv = dev->dev_private;
+	struct drm_i915_error_state *error;
+	unsigned long flags;
+
+	spin_lock_irqsave(&dev_priv->error_lock, flags);
+	if (!dev_priv->first_error) {
+		seq_printf(m, "no error state collected\n");
+		goto out;
+	}
+
+	error = dev_priv->first_error;
+
+	seq_printf(m, "EIR: 0x%08x\n", error->eir);
+	seq_printf(m, "  PGTBL_ER: 0x%08x\n", error->pgtbl_er);
+	seq_printf(m, "  INSTPM: 0x%08x\n", error->instpm);
+	seq_printf(m, "  IPEIR: 0x%08x\n", error->ipeir);
+	seq_printf(m, "  IPEHR: 0x%08x\n", error->ipehr);
+	seq_printf(m, "  INSTDONE: 0x%08x\n", error->instdone);
+	seq_printf(m, "  ACTHD: 0x%08x\n", error->acthd);
+	if (IS_I965G(dev)) {
+		seq_printf(m, "  INSTPS: 0x%08x\n", error->instps);
+		seq_printf(m, "  INSTDONE1: 0x%08x\n", error->instdone1);
+	}
+
+out:
+	spin_unlock_irqrestore(&dev_priv->error_lock, flags);
+
+	return 0;
+}
 
 static struct drm_info_list i915_gem_debugfs_list[] = {
 	{"i915_gem_active", i915_gem_object_list_info, 0, (void *) ACTIVE_LIST},
@@ -336,6 +369,7 @@ static struct drm_info_list i915_gem_debugfs_list[] = {
 	{"i915_ringbuffer_data", i915_ringbuffer_data, 0},
 	{"i915_ringbuffer_info", i915_ringbuffer_info, 0},
 	{"i915_batchbuffers", i915_batchbuffer_info, 0},
+	{"i915_error_state", i915_error_state, 0},
 };
 #define I915_GEM_DEBUGFS_ENTRIES ARRAY_SIZE(i915_gem_debugfs_list)
 

drivers/gpu/drm/i915/i915_irq.c

@@ -26,6 +26,7 @@
  *
  */
 
+#include <linux/sysrq.h>
 #include "drmP.h"
 #include "drm.h"
 #include "i915_drm.h"
@@ -41,9 +42,10 @@
  * we leave them always unmasked in IMR and then control enabling them through
  * PIPESTAT alone.
  */
-#define I915_INTERRUPT_ENABLE_FIX (I915_ASLE_INTERRUPT | \
-				   I915_DISPLAY_PIPE_A_EVENT_INTERRUPT |  \
-				   I915_DISPLAY_PIPE_B_EVENT_INTERRUPT)
+#define I915_INTERRUPT_ENABLE_FIX (I915_ASLE_INTERRUPT |		 \
+				   I915_DISPLAY_PIPE_A_EVENT_INTERRUPT | \
+				   I915_DISPLAY_PIPE_B_EVENT_INTERRUPT | \
+				   I915_RENDER_COMMAND_PARSER_ERROR_INTERRUPT)
 
 /** Interrupts that we mask and unmask at runtime. */
 #define I915_INTERRUPT_ENABLE_VAR (I915_USER_INTERRUPT)
@@ -288,6 +290,47 @@ irqreturn_t igdng_irq_handler(struct drm_device *dev)
 	return ret;
 }
 
+static void i915_capture_error_state(struct drm_device *dev)
+{
+	struct drm_i915_private *dev_priv = dev->dev_private;
+	struct drm_i915_error_state *error;
+	unsigned long flags;
+
+	spin_lock_irqsave(&dev_priv->error_lock, flags);
+	if (dev_priv->first_error)
+		goto out;
+
+	error = kmalloc(sizeof(*error), GFP_ATOMIC);
+	if (!error) {
+		DRM_DEBUG("out ot memory, not capturing error state\n");
+		goto out;
+	}
+
+	error->eir = I915_READ(EIR);
+	error->pgtbl_er = I915_READ(PGTBL_ER);
+	error->pipeastat = I915_READ(PIPEASTAT);
+	error->pipebstat = I915_READ(PIPEBSTAT);
+	error->instpm = I915_READ(INSTPM);
+	if (!IS_I965G(dev)) {
+		error->ipeir = I915_READ(IPEIR);
+		error->ipehr = I915_READ(IPEHR);
+		error->instdone = I915_READ(INSTDONE);
+		error->acthd = I915_READ(ACTHD);
+	} else {
+		error->ipeir = I915_READ(IPEIR_I965);
+		error->ipehr = I915_READ(IPEHR_I965);
+		error->instdone = I915_READ(INSTDONE_I965);
+		error->instps = I915_READ(INSTPS);
+		error->instdone1 = I915_READ(INSTDONE1);
+		error->acthd = I915_READ(ACTHD_I965);
+	}
+
+	dev_priv->first_error = error;
+
+out:
+	spin_unlock_irqrestore(&dev_priv->error_lock, flags);
+}
+
 irqreturn_t i915_driver_irq_handler(DRM_IRQ_ARGS)
 {
 	struct drm_device *dev = (struct drm_device *) arg;
@@ -362,6 +405,80 @@ irqreturn_t i915_driver_irq_handler(DRM_IRQ_ARGS)
 			I915_READ(PORT_HOTPLUG_STAT);
 		}
 
+		if (iir & I915_RENDER_COMMAND_PARSER_ERROR_INTERRUPT) {
+			u32 eir = I915_READ(EIR);
+
+			i915_capture_error_state(dev);
+
+			printk(KERN_ERR "render error detected, EIR: 0x%08x\n",
+			       eir);
+			if (eir & I915_ERROR_PAGE_TABLE) {
+				u32 pgtbl_err = I915_READ(PGTBL_ER);
+				printk(KERN_ERR "page table error\n");
+				printk(KERN_ERR "  PGTBL_ER: 0x%08x\n",
+				       pgtbl_err);
+				I915_WRITE(PGTBL_ER, pgtbl_err);
+				(void)I915_READ(PGTBL_ER);
+			}
+			if (eir & I915_ERROR_MEMORY_REFRESH) {
+				printk(KERN_ERR "memory refresh error\n");
+				printk(KERN_ERR "PIPEASTAT: 0x%08x\n",
+				       pipea_stats);
+				printk(KERN_ERR "PIPEBSTAT: 0x%08x\n",
+				       pipeb_stats);
+				/* pipestat has already been acked */
+			}
+			if (eir & I915_ERROR_INSTRUCTION) {
+				printk(KERN_ERR "instruction error\n");
+				printk(KERN_ERR "  INSTPM: 0x%08x\n",
+				       I915_READ(INSTPM));
+				if (!IS_I965G(dev)) {
+					u32 ipeir = I915_READ(IPEIR);
+
+					printk(KERN_ERR "  IPEIR: 0x%08x\n",
+					       I915_READ(IPEIR));
+					printk(KERN_ERR "  IPEHR: 0x%08x\n",
+						   I915_READ(IPEHR));
+					printk(KERN_ERR "  INSTDONE: 0x%08x\n",
+						   I915_READ(INSTDONE));
+					printk(KERN_ERR "  ACTHD: 0x%08x\n",
+						   I915_READ(ACTHD));
+					I915_WRITE(IPEIR, ipeir);
+					(void)I915_READ(IPEIR);
+				} else {
+					u32 ipeir = I915_READ(IPEIR_I965);
+
+					printk(KERN_ERR "  IPEIR: 0x%08x\n",
+					       I915_READ(IPEIR_I965));
+					printk(KERN_ERR "  IPEHR: 0x%08x\n",
+					       I915_READ(IPEHR_I965));
+					printk(KERN_ERR "  INSTDONE: 0x%08x\n",
+					       I915_READ(INSTDONE_I965));
+					printk(KERN_ERR "  INSTPS: 0x%08x\n",
+					       I915_READ(INSTPS));
+					printk(KERN_ERR "  INSTDONE1: 0x%08x\n",
+					       I915_READ(INSTDONE1));
+					printk(KERN_ERR "  ACTHD: 0x%08x\n",
+					       I915_READ(ACTHD_I965));
+					I915_WRITE(IPEIR_I965, ipeir);
+					(void)I915_READ(IPEIR_I965);
+				}
+			}
+
+			I915_WRITE(EIR, eir);
+			(void)I915_READ(EIR);
+			eir = I915_READ(EIR);
+			if (eir) {
+				/*
+				 * some errors might have become stuck,
+				 * mask them.
+				 */
+				DRM_ERROR("EIR stuck: 0x%08x, masking\n", eir);
+				I915_WRITE(EMR, I915_READ(EMR) | eir);
+				I915_WRITE(IIR, I915_RENDER_COMMAND_PARSER_ERROR_INTERRUPT);
+			}
+		}
+
 		I915_WRITE(IIR, iir);
 		new_iir = I915_READ(IIR); /* Flush posted writes */
 
@@ -732,6 +849,7 @@ int i915_driver_irq_postinstall(struct drm_device *dev)
 {
 	drm_i915_private_t *dev_priv = (drm_i915_private_t *) dev->dev_private;
 	u32 enable_mask = I915_INTERRUPT_ENABLE_FIX | I915_INTERRUPT_ENABLE_VAR;
+	u32 error_mask;
 
 	DRM_INIT_WAITQUEUE(&dev_priv->irq_queue);
 
@@ -768,6 +886,21 @@ int i915_driver_irq_postinstall(struct drm_device *dev)
 		i915_enable_irq(dev_priv, I915_DISPLAY_PORT_INTERRUPT);
 	}
 
+	/*
+	 * Enable some error detection, note the instruction error mask
+	 * bit is reserved, so we leave it masked.
+	 */
+	if (IS_G4X(dev)) {
+		error_mask = ~(GM45_ERROR_PAGE_TABLE |
+			       GM45_ERROR_MEM_PRIV |
+			       GM45_ERROR_CP_PRIV |
+			       I915_ERROR_MEMORY_REFRESH);
+	} else {
+		error_mask = ~(I915_ERROR_PAGE_TABLE |
+			       I915_ERROR_MEMORY_REFRESH);
+	}
+	I915_WRITE(EMR, error_mask);
+
 	/* Disable pipe interrupt enables, clear pending pipe status */
 	I915_WRITE(PIPEASTAT, I915_READ(PIPEASTAT) & 0x8000ffff);
 	I915_WRITE(PIPEBSTAT, I915_READ(PIPEBSTAT) & 0x8000ffff);

drivers/gpu/drm/i915/i915_reg.h

@@ -206,6 +206,7 @@
 /*
  * Instruction and interrupt control regs
  */
+#define PGTBL_ER	0x02024
 #define PRB0_TAIL	0x02030
 #define PRB0_HEAD	0x02034
 #define PRB0_START	0x02038
@@ -226,11 +227,18 @@
 #define PRB1_HEAD	0x02044 /* 915+ only */
 #define PRB1_START	0x02048 /* 915+ only */
 #define PRB1_CTL	0x0204c /* 915+ only */
+#define IPEIR_I965	0x02064
+#define IPEHR_I965	0x02068
+#define INSTDONE_I965	0x0206c
+#define INSTPS		0x02070 /* 965+ only */
+#define INSTDONE1	0x0207c /* 965+ only */
 #define ACTHD_I965	0x02074
 #define HWS_PGA		0x02080
 #define HWS_ADDRESS_MASK	0xfffff000
 #define HWS_START_ADDRESS_SHIFT	4
 #define IPEIR		0x02088
+#define IPEHR		0x0208c
+#define INSTDONE	0x02090
 #define NOPID		0x02094
 #define HWSTAM		0x02098
 #define SCPD0		0x0209c /* 915+ only */
@@ -258,6 +266,12 @@
 #define EIR		0x020b0
 #define EMR		0x020b4
 #define ESR		0x020b8
+#define   GM45_ERROR_PAGE_TABLE				(1<<5)
+#define   GM45_ERROR_MEM_PRIV				(1<<4)
+#define   I915_ERROR_PAGE_TABLE				(1<<4)
+#define   GM45_ERROR_CP_PRIV				(1<<3)
+#define   I915_ERROR_MEMORY_REFRESH			(1<<1)
+#define   I915_ERROR_INSTRUCTION			(1<<0)
 #define INSTPM	        0x020c0
 #define ACTHD	        0x020c8
 #define FW_BLC		0x020d8