Re: [Intel-gfx] [PATCH 4/7] drm/i915/guc: use the memcpy_from_wc call from the drm

[Lucas De Marchi]

On Tue, Feb 22, 2022 at 08:22:03PM +0530, Balasubramani Vivekanandan wrote:

memcpy_from_wc functions in i915_memcpy.c will be removed and replaced
by the implementation in drm_cache.c.
Updated to use the functions provided by drm_cache.c.

Signed-off-by: Balasubramani Vivekanandan <balasubramani.vivekanan...@intel.com>
---
drivers/gpu/drm/i915/gt/uc/intel_guc_log.c | 11 ++++++++---
1 file changed, 8 insertions(+), 3 deletions(-)

diff --git a/drivers/gpu/drm/i915/gt/uc/intel_guc_log.c 
b/drivers/gpu/drm/i915/gt/uc/intel_guc_log.c
index b53f61f3101f..1990762f07de 100644
--- a/drivers/gpu/drm/i915/gt/uc/intel_guc_log.c
+++ b/drivers/gpu/drm/i915/gt/uc/intel_guc_log.c
@@ -3,6 +3,7 @@
 * Copyright © 2014-2019 Intel Corporation
 */

+#include <drm/drm_cache.h>
#include <linux/debugfs.h>

#include "gt/intel_gt.h"
@@ -205,6 +206,7 @@ static void guc_read_update_log_buffer(struct intel_guc_log 
*log)
        enum guc_log_buffer_type type;
        void *src_data, *dst_data;
        bool new_overflow;
+       struct iosys_map src_map;

        mutex_lock(&log->relay.lock);

@@ -281,14 +283,17 @@ static void guc_read_update_log_buffer(struct 
intel_guc_log *log)
                }

                /* Just copy the newly written data */
+               iosys_map_set_vaddr(&src_map, src_data);

src is not guaranteed to come from system memory.... src is coming from:
intel_guc_allocate_vma(), that may call either  i915_gem_object_create_lmem()
or  i915_gem_object_create_shmem() depending if the platforma has lmem.

I guess you will  need to check if the obj is in lmem and initialize
src_map accordingly.

Lucas De Marchi

                if (read_offset > write_offset) {
-                       i915_memcpy_from_wc(dst_data, src_data, write_offset);
+                       drm_memcpy_from_wc_vaddr(dst_data, &src_map,
+                                                write_offset);
                        bytes_to_copy = buffer_size - read_offset;
                } else {
                        bytes_to_copy = write_offset - read_offset;
                }
-               i915_memcpy_from_wc(dst_data + read_offset,
-                                   src_data + read_offset, bytes_to_copy);
+               iosys_map_incr(&src_map, read_offset);
+               drm_memcpy_from_wc_vaddr(dst_data + read_offset, &src_map,
+                                        bytes_to_copy);

                src_data += buffer_size;
                dst_data += buffer_size;
--
2.25.1