Re: [PATCH v3 1/3] drm/msm/dpu: index dpu_kms->hw_vbif using vbif_idx

[Abhinav Kumar <quic_abhinavk@xxxxxxxxxxx>]

On 6/15/2022 5:57 AM, Dmitry Baryshkov wrote:
> Remove loops over hw_vbif. Instead always VBIF's idx as an index in the
> array. This fixes an error in dpu_kms_hw_init(), where we fill
> dpu_kms->hw_vbif[i], but check for an error pointer at
> dpu_kms->hw_vbif[vbif_idx].
>
> Fixes: 25fdd5933e4c ("drm/msm: Add SDM845 DPU support")
> Signed-off-by: Dmitry Baryshkov <dmitry.baryshkov@xxxxxxxxxx>
Reviewed-by: Abhinav Kumar <quic_abhinavk@xxxxxxxxxxx>
> ---
>   drivers/gpu/drm/msm/disp/dpu1/dpu_kms.c  | 12 ++++------
>   drivers/gpu/drm/msm/disp/dpu1/dpu_vbif.c | 29 +++++++++++-------------
>   2 files changed, 18 insertions(+), 23 deletions(-)
>
> diff --git a/drivers/gpu/drm/msm/disp/dpu1/dpu_kms.c b/drivers/gpu/drm/msm/disp/dpu1/dpu_kms.c
> index 2b9d931474e0..1255d00c92cf 100644
> --- a/drivers/gpu/drm/msm/disp/dpu1/dpu_kms.c
> +++ b/drivers/gpu/drm/msm/disp/dpu1/dpu_kms.c
> @@ -830,12 +830,10 @@ static void _dpu_kms_hw_destroy(struct dpu_kms *dpu_kms)
>   	_dpu_kms_mmu_destroy(dpu_kms);
>   
>   	if (dpu_kms->catalog) {
> -		for (i = 0; i < dpu_kms->catalog->vbif_count; i++) {
> -			u32 vbif_idx = dpu_kms->catalog->vbif[i].id;
> -
> -			if ((vbif_idx < VBIF_MAX) && dpu_kms->hw_vbif[vbif_idx]) {
> -				dpu_hw_vbif_destroy(dpu_kms->hw_vbif[vbif_idx]);
> -				dpu_kms->hw_vbif[vbif_idx] = NULL;
> +		for (i = 0; i < ARRAY_SIZE(dpu_kms->hw_vbif); i++) {
> +			if (dpu_kms->hw_vbif[i]) {
> +				dpu_hw_vbif_destroy(dpu_kms->hw_vbif[i]);
> +				dpu_kms->hw_vbif[i] = NULL;
>   			}
>   		}
>   	}
> @@ -1135,7 +1133,7 @@ static int dpu_kms_hw_init(struct msm_kms *kms)
>   	for (i = 0; i < dpu_kms->catalog->vbif_count; i++) {
>   		u32 vbif_idx = dpu_kms->catalog->vbif[i].id;
>   
> -		dpu_kms->hw_vbif[i] = dpu_hw_vbif_init(vbif_idx,
> +		dpu_kms->hw_vbif[vbif_idx] = dpu_hw_vbif_init(vbif_idx,
>   				dpu_kms->vbif[vbif_idx], dpu_kms->catalog);
>   		if (IS_ERR_OR_NULL(dpu_kms->hw_vbif[vbif_idx])) {
>   			rc = PTR_ERR(dpu_kms->hw_vbif[vbif_idx]);
> diff --git a/drivers/gpu/drm/msm/disp/dpu1/dpu_vbif.c b/drivers/gpu/drm/msm/disp/dpu1/dpu_vbif.c
> index 21d20373eb8b..a18fb649301c 100644
> --- a/drivers/gpu/drm/msm/disp/dpu1/dpu_vbif.c
> +++ b/drivers/gpu/drm/msm/disp/dpu1/dpu_vbif.c
> @@ -11,6 +11,14 @@
>   #include "dpu_hw_vbif.h"
>   #include "dpu_trace.h"
>   
> +static struct dpu_hw_vbif *dpu_get_vbif(struct dpu_kms *dpu_kms, enum dpu_vbif vbif_idx)
> +{
> +	if (vbif_idx < ARRAY_SIZE(dpu_kms->hw_vbif))
> +		return dpu_kms->hw_vbif[vbif_idx];
> +
> +	return NULL;
> +}
> +
>   /**
>    * _dpu_vbif_wait_for_xin_halt - wait for the xin to halt
>    * @vbif:	Pointer to hardware vbif driver
> @@ -148,20 +156,15 @@ static u32 _dpu_vbif_get_ot_limit(struct dpu_hw_vbif *vbif,
>   void dpu_vbif_set_ot_limit(struct dpu_kms *dpu_kms,
>   		struct dpu_vbif_set_ot_params *params)
>   {
> -	struct dpu_hw_vbif *vbif = NULL;
> +	struct dpu_hw_vbif *vbif;
>   	struct dpu_hw_mdp *mdp;
>   	bool forced_on = false;
>   	u32 ot_lim;
> -	int ret, i;
> +	int ret;
>   
>   	mdp = dpu_kms->hw_mdp;
>   
> -	for (i = 0; i < ARRAY_SIZE(dpu_kms->hw_vbif); i++) {
> -		if (dpu_kms->hw_vbif[i] &&
> -				dpu_kms->hw_vbif[i]->idx == params->vbif_idx)
> -			vbif = dpu_kms->hw_vbif[i];
> -	}
> -
> +	vbif = dpu_get_vbif(dpu_kms, params->vbif_idx);
>   	if (!vbif || !mdp) {
>   		DRM_DEBUG_ATOMIC("invalid arguments vbif %d mdp %d\n",
>   				vbif != NULL, mdp != NULL);
> @@ -204,7 +207,7 @@ void dpu_vbif_set_ot_limit(struct dpu_kms *dpu_kms,
>   void dpu_vbif_set_qos_remap(struct dpu_kms *dpu_kms,
>   		struct dpu_vbif_set_qos_params *params)
>   {
> -	struct dpu_hw_vbif *vbif = NULL;
> +	struct dpu_hw_vbif *vbif;
>   	struct dpu_hw_mdp *mdp;
>   	bool forced_on = false;
>   	const struct dpu_vbif_qos_tbl *qos_tbl;
> @@ -216,13 +219,7 @@ void dpu_vbif_set_qos_remap(struct dpu_kms *dpu_kms,
>   	}
>   	mdp = dpu_kms->hw_mdp;
>   
> -	for (i = 0; i < ARRAY_SIZE(dpu_kms->hw_vbif); i++) {
> -		if (dpu_kms->hw_vbif[i] &&
> -				dpu_kms->hw_vbif[i]->idx == params->vbif_idx) {
> -			vbif = dpu_kms->hw_vbif[i];
> -			break;
> -		}
> -	}
> +	vbif = dpu_get_vbif(dpu_kms, params->vbif_idx);
>   
>   	if (!vbif || !vbif->cap) {
>   		DPU_ERROR("invalid vbif %d\n", params->vbif_idx);