On 2/10/2025 1:01 PM, Jesse.zhang@xxxxxxx wrote:
> From: "Jesse.zhang@xxxxxxx" <Jesse.zhang@xxxxxxx>
>
> This patch refactors the SDMA reset functionality in the `sdma_v4_4_2` driver
> to improve modularity and support shared usage between AMDGPU and KFD. The
> changes include:
>
> 1. **Refactored SDMA Reset Logic**:
> - Split the `sdma_v4_4_2_reset_queue` function into two separate functions:
> - `sdma_v4_4_2_stop_queue`: Stops the SDMA queue before reset.
> - `sdma_v4_4_2_restore_queue`: Restores the SDMA queue after reset.
> - These functions are now used as callbacks for the shared reset mechanism.
>
> 2. **Added Callback Support**:
> - Introduced a new structure `sdma_v4_4_2_reset_funcs` to hold the stop and
> restore callbacks.
> - Added `sdma_v4_4_2_set_reset_funcs` to register these callbacks with the
> shared reset mechanism using `amdgpu_set_on_reset_callbacks`.
>
> 3. **Fixed Reset Queue Function**:
> - Modified `sdma_v4_4_2_reset_queue` to use the shared `amdgpu_sdma_reset_queue`
> function, ensuring consistency across the driver.
>
> This patch ensures that SDMA reset functionality is more modular, reusable, and
> aligned with the shared reset mechanism between AMDGPU and KFD.
>
> Suggested-by: Jiadong Zhu <Jiadong.Zhu@xxxxxxx>
> Signed-off-by: Jesse Zhang <jesse.zhang@xxxxxxx>
> ---
> drivers/gpu/drm/amd/amdgpu/sdma_v4_4_2.c | 32 +++++++++++++++++++++---
> 1 file changed, 28 insertions(+), 4 deletions(-)
>
> diff --git a/drivers/gpu/drm/amd/amdgpu/sdma_v4_4_2.c b/drivers/gpu/drm/amd/amdgpu/sdma_v4_4_2.c
> index 64c163dd708f..3e60456b0db0 100644
> --- a/drivers/gpu/drm/amd/amdgpu/sdma_v4_4_2.c
> +++ b/drivers/gpu/drm/amd/amdgpu/sdma_v4_4_2.c
> @@ -105,6 +105,7 @@ static void sdma_v4_4_2_set_buffer_funcs(struct amdgpu_device *adev);
> static void sdma_v4_4_2_set_vm_pte_funcs(struct amdgpu_device *adev);
> static void sdma_v4_4_2_set_irq_funcs(struct amdgpu_device *adev);
> static void sdma_v4_4_2_set_ras_funcs(struct amdgpu_device *adev);
> +static void sdma_v4_4_2_set_reset_funcs(struct amdgpu_device *adev);
>
> static u32 sdma_v4_4_2_get_reg_offset(struct amdgpu_device *adev,
> u32 instance, u32 offset)
> @@ -1330,6 +1331,7 @@ static int sdma_v4_4_2_early_init(struct amdgpu_ip_block *ip_block)
> sdma_v4_4_2_set_vm_pte_funcs(adev);
> sdma_v4_4_2_set_irq_funcs(adev);
> sdma_v4_4_2_set_ras_funcs(adev);
> + sdma_v4_4_2_set_reset_funcs(adev);
>
> return 0;
> }
> @@ -1605,8 +1607,14 @@ static int sdma_v4_4_2_soft_reset(struct amdgpu_ip_block *ip_block)
> static int sdma_v4_4_2_reset_queue(struct amdgpu_ring *ring, unsigned int vmid)
> {
> struct amdgpu_device *adev = ring->adev;
> - int i, r;
> + u32 id = GET_INST(SDMA0, ring->me);
> + return amdgpu_sdma_reset_instance(adev, id);
Looks like it may be better to pass the amdgpu_ring pointer as the
argument here as well as for pre/post reset calls.
> +}
> +
> +static int sdma_v4_4_2_stop_queue(struct amdgpu_device *adev, uint32_t instance_id)
> +{
> u32 inst_mask;
> + struct amdgpu_ring *ring = &adev->sdma.instance[instance_id].ring;
>
> if (amdgpu_sriov_vf(adev))
> return -EINVAL;
> @@ -1617,10 +1625,16 @@ static int sdma_v4_4_2_reset_queue(struct amdgpu_ring *ring, unsigned int vmid)
> if (adev->sdma.has_page_queue)
> sdma_v4_4_2_inst_page_stop(adev, inst_mask);
>
> - r = amdgpu_dpm_reset_sdma(adev, 1 << GET_INST(SDMA0, ring->me));
> - if (r)
> - return r;
> + return 0;
> +}
>
> +static int sdma_v4_4_2_restore_queue(struct amdgpu_device *adev, uint32_t instance_id)
> +{
> + int i;
> + u32 inst_mask;
> + struct amdgpu_ring *ring = &adev->sdma.instance[instance_id].ring;
> +
> + inst_mask = 1 << ring->me;
> udelay(50);
>
> for (i = 0; i < adev->usec_timeout; i++) {
> @@ -1638,6 +1652,16 @@ static int sdma_v4_4_2_reset_queue(struct amdgpu_ring *ring, unsigned int vmid)
> return sdma_v4_4_2_inst_start(adev, inst_mask, true);
> }
>
> +static struct sdma_on_reset_funcs sdma_v4_4_2_reset_funcs = {
> + .pre_reset = sdma_v4_4_2_stop_queue,
It's better to call these as prereset/postreset. That makes it a bit
easier to know when the function is used.
Thanks,
Lijo
> + .post_reset = sdma_v4_4_2_restore_queue,
> +};
> +
> +static void sdma_v4_4_2_set_reset_funcs(struct amdgpu_device *adev)
> +{
> + amdgpu_sdma_register_on_reset_callbacks(adev, &sdma_v4_4_2_reset_funcs);
> +}
> +
> static int sdma_v4_4_2_set_trap_irq_state(struct amdgpu_device *adev,
> struct amdgpu_irq_src *source,
> unsigned type,
