2021-12-15 21:48:49

by Yannick FERTRE

[permalink] [raw]
Subject: [PATCH 4/5] drm/stm: ltdc: add support of flexible pixel formats

This feature allows the generation of any RGB pixel format.
The list of supported formats is no longer linked to the
register LXPFCR_PF, that the reason why a list of drm formats is
defined for each display controller version.

Signed-off-by: Yannick Fertre <[email protected]>
---
drivers/gpu/drm/stm/ltdc.c | 196 ++++++++++++++++++++++++++-----------
drivers/gpu/drm/stm/ltdc.h | 5 +-
2 files changed, 145 insertions(+), 56 deletions(-)

diff --git a/drivers/gpu/drm/stm/ltdc.c b/drivers/gpu/drm/stm/ltdc.c
index 862d43fe3087..4d249bc99894 100644
--- a/drivers/gpu/drm/stm/ltdc.c
+++ b/drivers/gpu/drm/stm/ltdc.c
@@ -186,6 +186,7 @@
#define LXWVPCR_WVSPPOS GENMASK(26, 16) /* Window Vertical StoP POSition */

#define LXPFCR_PF GENMASK(2, 0) /* Pixel Format */
+#define PF_FLEXIBLE 0x7 /* Flexible Pixel Format selected */

#define LXCACR_CONSTA GENMASK(7, 0) /* CONSTant Alpha */

@@ -216,17 +217,18 @@ enum ltdc_pix_fmt {
/* RGB formats */
PF_ARGB8888, /* ARGB [32 bits] */
PF_RGBA8888, /* RGBA [32 bits] */
+ PF_ABGR8888, /* ABGR [32 bits] */
+ PF_BGRA8888, /* BGRA [32 bits] */
PF_RGB888, /* RGB [24 bits] */
+ PF_BGR888, /* BGR [24 bits] */
PF_RGB565, /* RGB [16 bits] */
+ PF_BGR565, /* BGR [16 bits] */
PF_ARGB1555, /* ARGB A:1 bit RGB:15 bits [16 bits] */
PF_ARGB4444, /* ARGB A:4 bits R/G/B: 4 bits each [16 bits] */
/* Indexed formats */
PF_L8, /* Indexed 8 bits [8 bits] */
PF_AL44, /* Alpha:4 bits + indexed 4 bits [8 bits] */
- PF_AL88, /* Alpha:8 bits + indexed 8 bits [16 bits] */
- PF_ABGR8888, /* ABGR [32 bits] */
- PF_BGRA8888, /* BGRA [32 bits] */
- PF_BGR565 /* RGB [16 bits] */
+ PF_AL88 /* Alpha:8 bits + indexed 8 bits [16 bits] */
};

/* The index gives the encoding of the pixel format for an HW version */
@@ -260,7 +262,53 @@ static const enum ltdc_pix_fmt ltdc_pix_fmt_a2[NB_PF] = {
PF_RGB565, /* 0x04 */
PF_BGR565, /* 0x05 */
PF_RGB888, /* 0x06 */
- PF_ARGB1555 /* 0x07 */
+ PF_NONE /* 0x07 */
+};
+
+static const u32 ltdc_drm_fmt_a0[] = {
+ DRM_FORMAT_ARGB8888,
+ DRM_FORMAT_XRGB8888,
+ DRM_FORMAT_RGB888,
+ DRM_FORMAT_RGB565,
+ DRM_FORMAT_ARGB1555,
+ DRM_FORMAT_XRGB1555,
+ DRM_FORMAT_ARGB4444,
+ DRM_FORMAT_XRGB4444,
+ DRM_FORMAT_C8
+};
+
+static const u32 ltdc_drm_fmt_a1[] = {
+ DRM_FORMAT_ARGB8888,
+ DRM_FORMAT_XRGB8888,
+ DRM_FORMAT_RGB888,
+ DRM_FORMAT_RGB565,
+ DRM_FORMAT_RGBA8888,
+ DRM_FORMAT_RGBX8888,
+ DRM_FORMAT_ARGB1555,
+ DRM_FORMAT_XRGB1555,
+ DRM_FORMAT_ARGB4444,
+ DRM_FORMAT_XRGB4444,
+ DRM_FORMAT_C8
+};
+
+static const u32 ltdc_drm_fmt_a2[] = {
+ DRM_FORMAT_ARGB8888,
+ DRM_FORMAT_XRGB8888,
+ DRM_FORMAT_ABGR8888,
+ DRM_FORMAT_XBGR8888,
+ DRM_FORMAT_RGBA8888,
+ DRM_FORMAT_RGBX8888,
+ DRM_FORMAT_BGRA8888,
+ DRM_FORMAT_BGRX8888,
+ DRM_FORMAT_RGB565,
+ DRM_FORMAT_BGR565,
+ DRM_FORMAT_RGB888,
+ DRM_FORMAT_BGR888,
+ DRM_FORMAT_ARGB1555,
+ DRM_FORMAT_XRGB1555,
+ DRM_FORMAT_ARGB4444,
+ DRM_FORMAT_XRGB4444,
+ DRM_FORMAT_C8
};

/* Layer register offsets */
@@ -386,16 +434,30 @@ static inline enum ltdc_pix_fmt to_ltdc_pixelformat(u32 drm_fmt)
case DRM_FORMAT_XRGB8888:
pf = PF_ARGB8888;
break;
+ case DRM_FORMAT_ABGR8888:
+ case DRM_FORMAT_XBGR8888:
+ pf = PF_ABGR8888;
+ break;
case DRM_FORMAT_RGBA8888:
case DRM_FORMAT_RGBX8888:
pf = PF_RGBA8888;
break;
+ case DRM_FORMAT_BGRA8888:
+ case DRM_FORMAT_BGRX8888:
+ pf = PF_BGRA8888;
+ break;
case DRM_FORMAT_RGB888:
pf = PF_RGB888;
break;
+ case DRM_FORMAT_BGR888:
+ pf = PF_BGR888;
+ break;
case DRM_FORMAT_RGB565:
pf = PF_RGB565;
break;
+ case DRM_FORMAT_BGR565:
+ pf = PF_BGR565;
+ break;
case DRM_FORMAT_ARGB1555:
case DRM_FORMAT_XRGB1555:
pf = PF_ARGB1555;
@@ -416,49 +478,66 @@ static inline enum ltdc_pix_fmt to_ltdc_pixelformat(u32 drm_fmt)
return pf;
}

-static inline u32 to_drm_pixelformat(enum ltdc_pix_fmt pf)
+static inline u32 ltdc_set_flexible_pixel_format(struct drm_plane *plane, enum ltdc_pix_fmt pix_fmt)
{
- switch (pf) {
- case PF_ARGB8888:
- return DRM_FORMAT_ARGB8888;
- case PF_RGBA8888:
- return DRM_FORMAT_RGBA8888;
- case PF_RGB888:
- return DRM_FORMAT_RGB888;
- case PF_RGB565:
- return DRM_FORMAT_RGB565;
+ struct ltdc_device *ldev = plane_to_ltdc(plane);
+ u32 lofs = plane->index * LAY_OFS, ret = PF_FLEXIBLE;
+ int psize, alen, apos, rlen, rpos, glen, gpos, blen, bpos;
+
+ switch (pix_fmt) {
+ case PF_BGR888:
+ psize = 3;
+ alen = 0; apos = 0; rlen = 8; rpos = 0;
+ glen = 8; gpos = 8; blen = 8; bpos = 16;
+ break;
case PF_ARGB1555:
- return DRM_FORMAT_ARGB1555;
+ psize = 2;
+ alen = 1; apos = 15; rlen = 5; rpos = 10;
+ glen = 5; gpos = 5; blen = 5; bpos = 0;
+ break;
case PF_ARGB4444:
- return DRM_FORMAT_ARGB4444;
+ psize = 2;
+ alen = 4; apos = 12; rlen = 4; rpos = 8;
+ glen = 4; gpos = 4; blen = 4; bpos = 0;
+ break;
case PF_L8:
- return DRM_FORMAT_C8;
- case PF_AL44: /* No DRM support */
- case PF_AL88: /* No DRM support */
- case PF_NONE:
+ psize = 1;
+ alen = 0; apos = 0; rlen = 8; rpos = 0;
+ glen = 8; gpos = 0; blen = 8; bpos = 0;
+ break;
+ case PF_AL44:
+ psize = 1;
+ alen = 4; apos = 4; rlen = 4; rpos = 0;
+ glen = 4; gpos = 0; blen = 4; bpos = 0;
+ break;
+ case PF_AL88:
+ psize = 2;
+ alen = 8; apos = 8; rlen = 8; rpos = 0;
+ glen = 8; gpos = 0; blen = 8; bpos = 0;
+ break;
default:
- return 0;
+ ret = NB_PF; /* error case, trace msg is handled by the caller */
+ break;
+ }
+
+ if (ret == PF_FLEXIBLE) {
+ regmap_write(ldev->regmap, LTDC_L1FPF0R + lofs,
+ (rlen << 14) + (rpos << 9) + (alen << 5) + apos);
+
+ regmap_write(ldev->regmap, LTDC_L1FPF1R + lofs,
+ (psize << 18) + (blen << 14) + (bpos << 9) + (glen << 5) + gpos);
}
+
+ return ret;
}

-static inline u32 get_pixelformat_without_alpha(u32 drm)
+/*
+ * All non-alpha color formats derived from native alpha color formats are
+ * either characterized by a FourCC format code
+ */
+static inline u32 is_xrgb(u32 drm)
{
- switch (drm) {
- case DRM_FORMAT_ARGB4444:
- return DRM_FORMAT_XRGB4444;
- case DRM_FORMAT_RGBA4444:
- return DRM_FORMAT_RGBX4444;
- case DRM_FORMAT_ARGB1555:
- return DRM_FORMAT_XRGB1555;
- case DRM_FORMAT_RGBA5551:
- return DRM_FORMAT_RGBX5551;
- case DRM_FORMAT_ARGB8888:
- return DRM_FORMAT_XRGB8888;
- case DRM_FORMAT_RGBA8888:
- return DRM_FORMAT_RGBX8888;
- default:
- return 0;
- }
+ return ((drm & 0xFF) == 'X' || ((drm >> 8) & 0xFF) == 'X');
}

static irqreturn_t ltdc_irq_thread(int irq, void *arg)
@@ -972,6 +1051,10 @@ static void ltdc_plane_atomic_update(struct drm_plane *plane,
if (ldev->caps.pix_fmt_hw[val] == pf)
break;

+ /* Use the flexible color format feature if necessary and available */
+ if (ldev->caps.pix_fmt_flex && val == NB_PF)
+ val = ltdc_set_flexible_pixel_format(plane, pf);
+
if (val == NB_PF) {
DRM_ERROR("Pixel format %.4s not supported\n",
(char *)&fb->format->format);
@@ -1110,29 +1193,23 @@ static struct drm_plane *ltdc_plane_create(struct drm_device *ddev,
struct device *dev = ddev->dev;
struct drm_plane *plane;
unsigned int i, nb_fmt = 0;
- u32 formats[NB_PF * 2];
- u32 drm_fmt, drm_fmt_no_alpha;
+ u32 *formats;
+ u32 drm_fmt;
const u64 *modifiers = ltdc_format_modifiers;
int ret;

- /* Get supported pixel formats */
- for (i = 0; i < NB_PF; i++) {
- drm_fmt = to_drm_pixelformat(ldev->caps.pix_fmt_hw[i]);
- if (!drm_fmt)
- continue;
- formats[nb_fmt++] = drm_fmt;
+ formats = devm_kzalloc(dev, ldev->caps.pix_fmt_nb * sizeof(*formats), GFP_KERNEL);

- /* Add the no-alpha related format if any & supported */
- drm_fmt_no_alpha = get_pixelformat_without_alpha(drm_fmt);
- if (!drm_fmt_no_alpha)
- continue;
+ for (i = 0; i < ldev->caps.pix_fmt_nb; i++) {
+ drm_fmt = ldev->caps.pix_fmt_drm[i];

/* Manage hw-specific capabilities */
- if (ldev->caps.non_alpha_only_l1 &&
- type != DRM_PLANE_TYPE_PRIMARY)
- continue;
+ if (ldev->caps.non_alpha_only_l1)
+ /* XR24 & RX24 like formats supported only on primary layer */
+ if (type != DRM_PLANE_TYPE_PRIMARY && is_xrgb(drm_fmt))
+ continue;

- formats[nb_fmt++] = drm_fmt_no_alpha;
+ formats[nb_fmt++] = drm_fmt;
}

plane = devm_kzalloc(dev, sizeof(*plane), GFP_KERNEL);
@@ -1311,6 +1388,9 @@ static int ltdc_get_caps(struct drm_device *ddev)
ldev->caps.layer_ofs = LAY_OFS_0;
ldev->caps.layer_regs = ltdc_layer_regs_a0;
ldev->caps.pix_fmt_hw = ltdc_pix_fmt_a0;
+ ldev->caps.pix_fmt_drm = ltdc_drm_fmt_a0;
+ ldev->caps.pix_fmt_nb = ARRAY_SIZE(ltdc_drm_fmt_a0);
+ ldev->caps.pix_fmt_flex = false;
/*
* Hw older versions support non-alpha color formats derived
* from native alpha color formats only on the primary layer.
@@ -1330,6 +1410,9 @@ static int ltdc_get_caps(struct drm_device *ddev)
ldev->caps.layer_ofs = LAY_OFS_0;
ldev->caps.layer_regs = ltdc_layer_regs_a1;
ldev->caps.pix_fmt_hw = ltdc_pix_fmt_a1;
+ ldev->caps.pix_fmt_drm = ltdc_drm_fmt_a1;
+ ldev->caps.pix_fmt_nb = ARRAY_SIZE(ltdc_drm_fmt_a1);
+ ldev->caps.pix_fmt_flex = false;
ldev->caps.non_alpha_only_l1 = false;
ldev->caps.pad_max_freq_hz = 150000000;
ldev->caps.nb_irq = 4;
@@ -1340,6 +1423,9 @@ static int ltdc_get_caps(struct drm_device *ddev)
ldev->caps.layer_ofs = LAY_OFS_1;
ldev->caps.layer_regs = ltdc_layer_regs_a2;
ldev->caps.pix_fmt_hw = ltdc_pix_fmt_a2;
+ ldev->caps.pix_fmt_drm = ltdc_drm_fmt_a2;
+ ldev->caps.pix_fmt_nb = ARRAY_SIZE(ltdc_drm_fmt_a2);
+ ldev->caps.pix_fmt_flex = true;
ldev->caps.non_alpha_only_l1 = false;
ldev->caps.pad_max_freq_hz = 90000000;
ldev->caps.nb_irq = 2;
diff --git a/drivers/gpu/drm/stm/ltdc.h b/drivers/gpu/drm/stm/ltdc.h
index 68a5a199e320..adc4f9cf7f95 100644
--- a/drivers/gpu/drm/stm/ltdc.h
+++ b/drivers/gpu/drm/stm/ltdc.h
@@ -17,7 +17,10 @@ struct ltdc_caps {
u32 layer_ofs; /* layer offset for applicable regs */
const u32 *layer_regs; /* layer register offset */
u32 bus_width; /* bus width (32 or 64 bits) */
- const u32 *pix_fmt_hw; /* supported pixel formats */
+ const u32 *pix_fmt_hw; /* supported hw pixel formats */
+ const u32 *pix_fmt_drm; /* supported drm pixel formats */
+ int pix_fmt_nb; /* number of pixel format */
+ bool pix_fmt_flex; /* pixel format flexibility supported */
bool non_alpha_only_l1; /* non-native no-alpha formats on layer 1 */
int pad_max_freq_hz; /* max frequency supported by pad */
int nb_irq; /* number of hardware interrupts */
--
2.17.1



2022-01-04 10:27:24

by Philippe CORNU

[permalink] [raw]
Subject: Re: [PATCH 4/5] drm/stm: ltdc: add support of flexible pixel formats



On 12/15/21 10:48 PM, Yannick Fertre wrote:
> This feature allows the generation of any RGB pixel format.
> The list of supported formats is no longer linked to the
> register LXPFCR_PF, that the reason why a list of drm formats is
> defined for each display controller version.
>
> Signed-off-by: Yannick Fertre <[email protected]>
> ---
> drivers/gpu/drm/stm/ltdc.c | 196 ++++++++++++++++++++++++++-----------
> drivers/gpu/drm/stm/ltdc.h | 5 +-
> 2 files changed, 145 insertions(+), 56 deletions(-)
>

Hi Yannick,
many thanks for your patch.
Nice hw feature.
Acked-by: Philippe Cornu <[email protected]>
Reviewed-by: Philippe Cornu <[email protected]>
Philippe :-)

2022-01-13 10:21:16

by Raphael Gallais-Pou

[permalink] [raw]
Subject: Re: [PATCH 4/5] drm/stm: ltdc: add support of flexible pixel formats


On 12/15/21 10:48 PM, Yannick Fertre wrote:
> This feature allows the generation of any RGB pixel format.
> The list of supported formats is no longer linked to the
> register LXPFCR_PF, that the reason why a list of drm formats is
> defined for each display controller version.
>
> Signed-off-by: Yannick Fertre <[email protected]>
> ---
> drivers/gpu/drm/stm/ltdc.c | 196 ++++++++++++++++++++++++++-----------
> drivers/gpu/drm/stm/ltdc.h | 5 +-
> 2 files changed, 145 insertions(+), 56 deletions(-)


Hello Yannick,


Reviewed-by: Raphael Gallais-Pou <[email protected]>
Tested-by: Raphael Gallais-Pou <[email protected]>

Many thanks, this is an interesting patch.

Raphaƫl