[PATCH] Revert "accel/ivpu: Use cached buffers for FW loading"

[Stanislaw Gruszka]

This reverts commit 645d694559cab36fe6a57c717efcfa27d9321396.

The commit cause issues with memory access from the device side.
Switch back to write-combined memory mappings until the issues
will be properly addressed.

Add extra wmb() needed when boot_params->save_restore_ret_address() is
modified.

Reviewed-by: Karol Wachowski <karol.wachow...@linux.intel.com>
Signed-off-by: Stanislaw Gruszka <stanislaw.grus...@linux.intel.com>
---
 drivers/accel/ivpu/ivpu_fw.c  | 9 ++++-----
 drivers/accel/ivpu/ivpu_gem.h | 5 -----
 2 files changed, 4 insertions(+), 10 deletions(-)

diff --git a/drivers/accel/ivpu/ivpu_fw.c b/drivers/accel/ivpu/ivpu_fw.c
index 0191cf8e5964..a277bbae78fc 100644
--- a/drivers/accel/ivpu/ivpu_fw.c
+++ b/drivers/accel/ivpu/ivpu_fw.c
@@ -220,8 +220,7 @@ static int ivpu_fw_mem_init(struct ivpu_device *vdev)
        if (ret)
                return ret;
 
-       fw->mem = ivpu_bo_alloc_internal(vdev, fw->runtime_addr, 
fw->runtime_size,
-                                        DRM_IVPU_BO_CACHED | 
DRM_IVPU_BO_NOSNOOP);
+       fw->mem = ivpu_bo_alloc_internal(vdev, fw->runtime_addr, 
fw->runtime_size, DRM_IVPU_BO_WC);
        if (!fw->mem) {
                ivpu_err(vdev, "Failed to allocate firmware runtime memory\n");
                return -ENOMEM;
@@ -331,7 +330,7 @@ int ivpu_fw_load(struct ivpu_device *vdev)
                memset(start, 0, size);
        }
 
-       clflush_cache_range(fw->mem->kvaddr, fw->mem->base.size);
+       wmb(); /* Flush WC buffers after writing fw->mem */
 
        return 0;
 }
@@ -433,7 +432,7 @@ void ivpu_fw_boot_params_setup(struct ivpu_device *vdev, 
struct vpu_boot_params
        if (!ivpu_fw_is_cold_boot(vdev)) {
                boot_params->save_restore_ret_address = 0;
                vdev->pm->is_warmboot = true;
-               clflush_cache_range(vdev->fw->mem->kvaddr, SZ_4K);
+               wmb(); /* Flush WC buffers after writing 
save_restore_ret_address */
                return;
        }
 
@@ -495,7 +494,7 @@ void ivpu_fw_boot_params_setup(struct ivpu_device *vdev, 
struct vpu_boot_params
        boot_params->punit_telemetry_sram_size = 
ivpu_hw_reg_telemetry_size_get(vdev);
        boot_params->vpu_telemetry_enable = 
ivpu_hw_reg_telemetry_enable_get(vdev);
 
-       clflush_cache_range(vdev->fw->mem->kvaddr, SZ_4K);
+       wmb(); /* Flush WC buffers after writing bootparams */
 
        ivpu_fw_boot_params_print(vdev, boot_params);
 }
diff --git a/drivers/accel/ivpu/ivpu_gem.h b/drivers/accel/ivpu/ivpu_gem.h
index f4130586ff1b..6b0ceda5f253 100644
--- a/drivers/accel/ivpu/ivpu_gem.h
+++ b/drivers/accel/ivpu/ivpu_gem.h
@@ -8,8 +8,6 @@
 #include <drm/drm_gem.h>
 #include <drm/drm_mm.h>
 
-#define DRM_IVPU_BO_NOSNOOP       0x10000000
-
 struct dma_buf;
 struct ivpu_bo_ops;
 struct ivpu_file_priv;
@@ -85,9 +83,6 @@ static inline u32 ivpu_bo_cache_mode(struct ivpu_bo *bo)
 
 static inline bool ivpu_bo_is_snooped(struct ivpu_bo *bo)
 {
-       if (bo->flags & DRM_IVPU_BO_NOSNOOP)
-               return false;
-
        return ivpu_bo_cache_mode(bo) == DRM_IVPU_BO_CACHED;
 }
 
-- 
2.25.1