2022-02-22 12:39:08

by Colin Ian King

Subject: [PATCH] drm/i915: make a handful of read-only arrays static const

Don't populate the read-only arrays on the stack but instead make
them static const. Also makes the object code a little smaller.
Reformat the statements to clear up checkpatch warning.

Signed-off-by: Colin Ian King <[email protected]>
---
drivers/gpu/drm/i915/display/intel_vdsc.c | 16 ++++++++++++----
1 file changed, 12 insertions(+), 4 deletions(-)

diff --git a/drivers/gpu/drm/i915/display/intel_vdsc.c b/drivers/gpu/drm/i915/display/intel_vdsc.c
index 3faea903b9ae..d49f66237ec3 100644
--- a/drivers/gpu/drm/i915/display/intel_vdsc.c
+++ b/drivers/gpu/drm/i915/display/intel_vdsc.c
@@ -378,10 +378,18 @@ calculate_rc_params(struct rc_parameters *rc,
{
int bpc = vdsc_cfg->bits_per_component;
int bpp = vdsc_cfg->bits_per_pixel >> 4;
- int ofs_und6[] = { 0, -2, -2, -4, -6, -6, -8, -8, -8, -10, -10, -12, -12, -12, -12 };
- int ofs_und8[] = { 2, 0, 0, -2, -4, -6, -8, -8, -8, -10, -10, -10, -12, -12, -12 };
- int ofs_und12[] = { 2, 0, 0, -2, -4, -6, -8, -8, -8, -10, -10, -10, -12, -12, -12 };
- int ofs_und15[] = { 10, 8, 6, 4, 2, 0, -2, -4, -6, -8, -10, -10, -12, -12, -12 };
+ static const int ofs_und6[] = {
+ 0, -2, -2, -4, -6, -6, -8, -8, -8, -10, -10, -12, -12, -12, -12
+ };
+ static const int ofs_und8[] = {
+ 2, 0, 0, -2, -4, -6, -8, -8, -8, -10, -10, -10, -12, -12, -12
+ };
+ static const int ofs_und12[] = {
+ 2, 0, 0, -2, -4, -6, -8, -8, -8, -10, -10, -10, -12, -12, -12
+ };
+ static const int ofs_und15[] = {
+ 10, 8, 6, 4, 2, 0, -2, -4, -6, -8, -10, -10, -12, -12, -12
+ };
int qp_bpc_modifier = (bpc - 8) * 2;
u32 res, buf_i, bpp_i;

--
2.34.1

2022-02-22 12:56:36

by Jani Nikula

Subject: Re: [PATCH] drm/i915: make a handful of read-only arrays static const

On Tue, 22 Feb 2022, Colin Ian King <[email protected]> wrote:
> Don't populate the read-only arrays on the stack but instead make
> them static const. Also makes the object code a little smaller.
> Reformat the statements to clear up checkpatch warning.
>
> Signed-off-by: Colin Ian King <[email protected]>
> ---
> drivers/gpu/drm/i915/display/intel_vdsc.c | 16 ++++++++++++----
> 1 file changed, 12 insertions(+), 4 deletions(-)
>
> diff --git a/drivers/gpu/drm/i915/display/intel_vdsc.c b/drivers/gpu/drm/i915/display/intel_vdsc.c
> index 3faea903b9ae..d49f66237ec3 100644
> --- a/drivers/gpu/drm/i915/display/intel_vdsc.c
> +++ b/drivers/gpu/drm/i915/display/intel_vdsc.c
> @@ -378,10 +378,18 @@ calculate_rc_params(struct rc_parameters *rc,
> {
> int bpc = vdsc_cfg->bits_per_component;
> int bpp = vdsc_cfg->bits_per_pixel >> 4;
> - int ofs_und6[] = { 0, -2, -2, -4, -6, -6, -8, -8, -8, -10, -10, -12, -12, -12, -12 };
> - int ofs_und8[] = { 2, 0, 0, -2, -4, -6, -8, -8, -8, -10, -10, -10, -12, -12, -12 };
> - int ofs_und12[] = { 2, 0, 0, -2, -4, -6, -8, -8, -8, -10, -10, -10, -12, -12, -12 };
> - int ofs_und15[] = { 10, 8, 6, 4, 2, 0, -2, -4, -6, -8, -10, -10, -12, -12, -12 };
> + static const int ofs_und6[] = {
> + 0, -2, -2, -4, -6, -6, -8, -8, -8, -10, -10, -12, -12, -12, -12
> + };
> + static const int ofs_und8[] = {
> + 2, 0, 0, -2, -4, -6, -8, -8, -8, -10, -10, -10, -12, -12, -12
> + };
> + static const int ofs_und12[] = {
> + 2, 0, 0, -2, -4, -6, -8, -8, -8, -10, -10, -10, -12, -12, -12
> + };

Hmm, I wonder why the same values are duplicated in ofs_und8 and
ofs_und12. Cc: Vandita, Manasi.

Regardless, the patch is sane.

Reviewed-by: Jani Nikula <[email protected]>

> + static const int ofs_und15[] = {
> + 10, 8, 6, 4, 2, 0, -2, -4, -6, -8, -10, -10, -12, -12, -12
> + };
> int qp_bpc_modifier = (bpc - 8) * 2;
> u32 res, buf_i, bpp_i;

--
Jani Nikula, Intel Open Source Graphics Center

2022-02-22 21:46:53

by Ville Syrjälä

Subject: Re: [Intel-gfx] [PATCH] drm/i915: make a handful of read-only arrays static const

On Tue, Feb 22, 2022 at 12:03:23PM +0000, Colin Ian King wrote:
> Don't populate the read-only arrays on the stack but instead make
> them static const. Also makes the object code a little smaller.
> Reformat the statements to clear up checkpatch warning.
>
> Signed-off-by: Colin Ian King <[email protected]>
> ---
> drivers/gpu/drm/i915/display/intel_vdsc.c | 16 ++++++++++++----
> 1 file changed, 12 insertions(+), 4 deletions(-)
>
> diff --git a/drivers/gpu/drm/i915/display/intel_vdsc.c b/drivers/gpu/drm/i915/display/intel_vdsc.c
> index 3faea903b9ae..d49f66237ec3 100644
> --- a/drivers/gpu/drm/i915/display/intel_vdsc.c
> +++ b/drivers/gpu/drm/i915/display/intel_vdsc.c
> @@ -378,10 +378,18 @@ calculate_rc_params(struct rc_parameters *rc,
> {
> int bpc = vdsc_cfg->bits_per_component;
> int bpp = vdsc_cfg->bits_per_pixel >> 4;
> - int ofs_und6[] = { 0, -2, -2, -4, -6, -6, -8, -8, -8, -10, -10, -12, -12, -12, -12 };
> - int ofs_und8[] = { 2, 0, 0, -2, -4, -6, -8, -8, -8, -10, -10, -10, -12, -12, -12 };
> - int ofs_und12[] = { 2, 0, 0, -2, -4, -6, -8, -8, -8, -10, -10, -10, -12, -12, -12 };
> - int ofs_und15[] = { 10, 8, 6, 4, 2, 0, -2, -4, -6, -8, -10, -10, -12, -12, -12 };
> + static const int ofs_und6[] = {
> + 0, -2, -2, -4, -6, -6, -8, -8, -8, -10, -10, -12, -12, -12, -12
> + };
> + static const int ofs_und8[] = {
> + 2, 0, 0, -2, -4, -6, -8, -8, -8, -10, -10, -10, -12, -12, -12
> + };
> + static const int ofs_und12[] = {
> + 2, 0, 0, -2, -4, -6, -8, -8, -8, -10, -10, -10, -12, -12, -12
> + };
> + static const int ofs_und15[] = {
> + 10, 8, 6, 4, 2, 0, -2, -4, -6, -8, -10, -10, -12, -12, -12
> + };

Please shrink to s8 while at it.

> int qp_bpc_modifier = (bpc - 8) * 2;
> u32 res, buf_i, bpp_i;
>
> --
> 2.34.1

--
Ville Syrj?l?
Intel