drm/i915: Add Guc/HuC firmware details to error state

Include GuC and HuC firmware details in captured error state
to provide additional debug information. To reuse existing
uc firmware pretty printer, introduce new drm-printer variant
that works with our i915_error_state_buf output. Also update
uc firmware pretty printer to accept const input.

v2: don't rely on current caps (Chris)
    dump correct fw info (Michal)
v3: simplify capture of custom paths (Chris)
v4: improve 'why' comment (Joonas)
    trim output if no fw path (Michal)
    group code around uc error state (Michal)
v5: use error in cleanup_uc (Michal)

Suggested-by: Chris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: Michal Wajdeczko <michal.wajdeczko@intel.com>
Cc: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Joonas Lahtinen <joonas.lahtinen@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20171026173657.49648-1-michal.wajdeczko@intel.com
[ickle: allow printing uc_fw after allocation failure]
Reviewed-by: Chris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>

drivers/gpu/drm/i915/i915_drv.h

@@ -913,6 +913,11 @@ struct i915_gpu_state {
 	struct intel_device_info device_info;
 	struct i915_params params;
 
+	struct i915_error_uc {
+		struct intel_uc_fw guc_fw;
+		struct intel_uc_fw huc_fw;
+	} uc;
+
 	/* Generic register state */
 	u32 eir;
 	u32 pgtbl_er;

drivers/gpu/drm/i915/i915_gpu_error.c

@@ -30,6 +30,8 @@
 #include <generated/utsrelease.h>
 #include <linux/stop_machine.h>
 #include <linux/zlib.h>
+#include <drm/drm_print.h>
+
 #include "i915_drv.h"
 
 static const char *engine_str(int engine)
@@ -175,6 +177,21 @@ static void i915_error_puts(struct drm_i915_error_state_buf *e,
 #define err_printf(e, ...) i915_error_printf(e, __VA_ARGS__)
 #define err_puts(e, s) i915_error_puts(e, s)
 
+static void __i915_printfn_error(struct drm_printer *p, struct va_format *vaf)
+{
+	i915_error_vprintf(p->arg, vaf->fmt, *vaf->va);
+}
+
+static inline struct drm_printer
+i915_error_printer(struct drm_i915_error_state_buf *e)
+{
+	struct drm_printer p = {
+		.printfn = __i915_printfn_error,
+		.arg = e,
+	};
+	return p;
+}
+
 #ifdef CONFIG_DRM_I915_COMPRESS_ERROR
 
 struct compress {
@@ -589,6 +606,20 @@ static void err_print_pciid(struct drm_i915_error_state_buf *m,
 		   pdev->subsystem_device);
 }
 
+static void err_print_uc(struct drm_i915_error_state_buf *m,
+			 const struct i915_error_uc *error_uc)
+{
+	struct drm_printer p = i915_error_printer(m);
+	const struct i915_gpu_state *error =
+		container_of(error_uc, typeof(*error), uc);
+
+	if (!error->device_info.has_guc)
+		return;
+
+	intel_uc_fw_dump(&error_uc->guc_fw, &p);
+	intel_uc_fw_dump(&error_uc->huc_fw, &p);
+}
+
 int i915_error_state_to_str(struct drm_i915_error_state_buf *m,
 			    const struct i915_gpu_state *error)
 {
@@ -773,6 +804,7 @@ int i915_error_state_to_str(struct drm_i915_error_state_buf *m,
 
 	err_print_capabilities(m, &error->device_info);
 	err_print_params(m, &error->params);
+	err_print_uc(m, &error->uc);
 
 	if (m->bytes == 0 && m->err)
 		return m->err;
@@ -831,6 +863,14 @@ static __always_inline void free_param(const char *type, void *x)
 		kfree(*(void **)x);
 }
 
+static void cleanup_uc_state(struct i915_gpu_state *error)
+{
+	struct i915_error_uc *error_uc = &error->uc;
+
+	kfree(error_uc->guc_fw.path);
+	kfree(error_uc->huc_fw.path);
+}
+
 void __i915_gpu_state_free(struct kref *error_ref)
 {
 	struct i915_gpu_state *error =
@@ -870,6 +910,8 @@ void __i915_gpu_state_free(struct kref *error_ref)
 	I915_PARAMS_FOR_EACH(FREE);
 #undef FREE
 
+	cleanup_uc_state(error);
+
 	kfree(error);
 }
 
@@ -1559,6 +1601,26 @@ static void i915_capture_pinned_buffers(struct drm_i915_private *dev_priv,
 	error->pinned_bo = bo;
 }
 
+static void capture_uc_state(struct i915_gpu_state *error)
+{
+	struct drm_i915_private *i915 = error->i915;
+	struct i915_error_uc *error_uc = &error->uc;
+
+	/* Capturing uC state won't be useful if there is no GuC */
+	if (!error->device_info.has_guc)
+		return;
+
+	error_uc->guc_fw = i915->guc.fw;
+	error_uc->huc_fw = i915->huc.fw;
+
+	/* Non-default firmware paths will be specified by the modparam.
+	 * As modparams are generally accesible from the userspace make
+	 * explicit copies of the firmware paths.
+	 */
+	error_uc->guc_fw.path = kstrdup(i915->guc.fw.path, GFP_ATOMIC);
+	error_uc->huc_fw.path = kstrdup(i915->huc.fw.path, GFP_ATOMIC);
+}
+
 static void i915_gem_capture_guc_log_buffer(struct drm_i915_private *dev_priv,
 					    struct i915_gpu_state *error)
 {
@@ -1710,6 +1772,8 @@ static int capture(void *data)
 	I915_PARAMS_FOR_EACH(DUP);
 #undef DUP
 
+	capture_uc_state(error);
+
 	i915_capture_gen_state(error->i915, error);
 	i915_capture_reg_state(error->i915, error);
 	i915_gem_record_fences(error->i915, error);

drivers/gpu/drm/i915/intel_uc_fw.c

@@ -299,7 +299,7 @@ void intel_uc_fw_fini(struct intel_uc_fw *uc_fw)
  *
  * Pretty printer for uC firmware.
  */
-void intel_uc_fw_dump(struct intel_uc_fw *uc_fw, struct drm_printer *p)
+void intel_uc_fw_dump(const struct intel_uc_fw *uc_fw, struct drm_printer *p)
 {
 	drm_printf(p, "%s firmware: %s\n",
 		   intel_uc_fw_type_repr(uc_fw->type), uc_fw->path);

drivers/gpu/drm/i915/intel_uc_fw.h

@@ -116,6 +116,6 @@ int intel_uc_fw_upload(struct intel_uc_fw *uc_fw,
 		       int (*xfer)(struct intel_uc_fw *uc_fw,
 				   struct i915_vma *vma));
 void intel_uc_fw_fini(struct intel_uc_fw *uc_fw);
-void intel_uc_fw_dump(struct intel_uc_fw *uc_fw, struct drm_printer *p);
+void intel_uc_fw_dump(const struct intel_uc_fw *uc_fw, struct drm_printer *p);
 
 #endif