[PATCH v3 08/16] drm: sti: add GDP layer
From: Benjamin Gaignard
Date: Tue May 20 2014 - 10:01:48 EST
Generic Display Pipeline are one of the compositor input sub-devices.
GDP are dedicated to graphic input like RGB plans.
Signed-off-by: Benjamin Gaignard <benjamin.gaignard@xxxxxxxxxx>
---
drivers/gpu/drm/sti/Makefile | 3 +-
drivers/gpu/drm/sti/sti_gdp.c | 491 ++++++++++++++++++++++++++++++++++++++++
drivers/gpu/drm/sti/sti_gdp.h | 73 ++++++
drivers/gpu/drm/sti/sti_layer.h | 5 +
4 files changed, 571 insertions(+), 1 deletion(-)
create mode 100644 drivers/gpu/drm/sti/sti_gdp.c
create mode 100644 drivers/gpu/drm/sti/sti_gdp.h
diff --git a/drivers/gpu/drm/sti/Makefile b/drivers/gpu/drm/sti/Makefile
index 45536c3..cc04475 100644
--- a/drivers/gpu/drm/sti/Makefile
+++ b/drivers/gpu/drm/sti/Makefile
@@ -1,10 +1,11 @@
ccflags-y := -Iinclude/drm
-stidrm-y := sti_tvout.o \
+stidrm-y := sti_tvout.o \
sti_hdmi.o \
sti_hdmi_tx3g0c55phy.o \
sti_hdmi_tx3g4c28phy.o \
sti_hda.o \
+ sti_gdp.o \
sti_ddc.o
obj-$(CONFIG_VTAC_STI) += sti_vtac_tx.o sti_vtac_rx.o
diff --git a/drivers/gpu/drm/sti/sti_gdp.c b/drivers/gpu/drm/sti/sti_gdp.c
new file mode 100644
index 0000000..00ff7f9
--- /dev/null
+++ b/drivers/gpu/drm/sti/sti_gdp.c
@@ -0,0 +1,491 @@
+/*
+ * Copyright (C) STMicroelectronics SA 2013
+ * Authors: Benjamin Gaignard <benjamin.gaignard@xxxxxx>
+ * Fabien Dessenne <fabien.dessenne@xxxxxx>
+ * for STMicroelectronics.
+ * License terms: GNU General Public License (GPL), version 2
+ */
+
+#include <linux/clk.h>
+#include <linux/dma-mapping.h>
+
+#include "sti_layer.h"
+#include "sti_gdp.h"
+#include "sti_vtg_utils.h"
+
+#define ENA_COLOR_FILL (1 << 8)
+#define WAIT_NEXT_VSYNC (1 << 31)
+
+/* GDP color formats */
+#define GDP_RGB565 0x00
+#define GDP_RGB888 0x01
+#define GDP_RGB888_32 0x02
+#define GDP_ARGB8565 0x04
+#define GDP_ARGB8888 0x05
+#define GDP_ARGB1555 0x06
+#define GDP_ARGB4444 0x07
+#define GDP_CLUT8 0x0B
+#define GDP_YCBR888 0x10
+#define GDP_YCBR422R 0x12
+#define GDP_AYCBR8888 0x15
+
+#define GAM_GDP_CTL_OFFSET 0x00
+#define GAM_GDP_AGC_OFFSET 0x04
+#define GAM_GDP_VPO_OFFSET 0x0C
+#define GAM_GDP_VPS_OFFSET 0x10
+#define GAM_GDP_PML_OFFSET 0x14
+#define GAM_GDP_PMP_OFFSET 0x18
+#define GAM_GDP_SIZE_OFFSET 0x1C
+#define GAM_GDP_NVN_OFFSET 0x24
+#define GAM_GDP_KEY1_OFFSET 0x28
+#define GAM_GDP_KEY2_OFFSET 0x2C
+#define GAM_GDP_PPT_OFFSET 0x34
+#define GAM_GDP_CML_OFFSET 0x3C
+#define GAM_GDP_MST_OFFSET 0x68
+
+#define GAM_GDP_ALPHARANGE_255 (1 << 5)
+#define GAM_GDP_AGC_FULL_RANGE 0x00808080
+#define GAM_GDP_PPT_IGNORE ((1 << 1) | (1 << 0))
+#define GAM_GDP_SIZE_MAX 0x7FF
+
+static const uint32_t gdp_supported_formats[] = {
+ DRM_FORMAT_XRGB8888,
+ DRM_FORMAT_ARGB8888,
+ DRM_FORMAT_ARGB4444,
+ DRM_FORMAT_ARGB1555,
+ DRM_FORMAT_RGB565,
+ DRM_FORMAT_RGB888,
+ DRM_FORMAT_AYUV,
+ DRM_FORMAT_YUV444,
+ DRM_FORMAT_VYUY,
+ DRM_FORMAT_C8,
+};
+
+static const uint32_t *sti_gdp_get_formats(void)
+{
+ return gdp_supported_formats;
+}
+
+static int sti_gdp_get_nb_formats(void)
+{
+ return ARRAY_SIZE(gdp_supported_formats);
+}
+
+static int sti_gdp_fourcc2format(int fourcc)
+{
+ switch (fourcc) {
+ case DRM_FORMAT_XRGB8888:
+ return GDP_RGB888_32;
+ case DRM_FORMAT_ARGB8888:
+ return GDP_ARGB8888;
+ case DRM_FORMAT_ARGB4444:
+ return GDP_ARGB4444;
+ case DRM_FORMAT_ARGB1555:
+ return GDP_ARGB1555;
+ case DRM_FORMAT_RGB565:
+ return GDP_RGB565;
+ case DRM_FORMAT_RGB888:
+ return GDP_RGB888;
+ case DRM_FORMAT_AYUV:
+ return GDP_AYCBR8888;
+ case DRM_FORMAT_YUV444:
+ return GDP_YCBR888;
+ case DRM_FORMAT_VYUY:
+ return GDP_YCBR422R;
+ case DRM_FORMAT_C8:
+ return GDP_CLUT8;
+ }
+ return -1;
+}
+
+static int sti_gdp_get_alpharange(int format)
+{
+ switch (format) {
+ case GDP_ARGB8565:
+ case GDP_ARGB8888:
+ case GDP_AYCBR8888:
+ return GAM_GDP_ALPHARANGE_255;
+ }
+ return 0;
+}
+
+/**
+ * sti_gdp_get_free_nodes
+ * @layer: gdp layer
+ *
+ * Look for a GDP node list that is not currently read by the HW.
+ *
+ * RETURNS:
+ * Pointer to the free GDP node list
+ */
+static struct sti_gdp_node_list *sti_gdp_get_free_nodes(struct sti_layer *layer)
+{
+ int hw_nvn;
+ void *virt_nvn;
+ struct sti_gdp *gdp = layer->gdp;
+ int i;
+
+ hw_nvn = readl(gdp->regs + GAM_GDP_NVN_OFFSET);
+ if (!hw_nvn)
+ goto end;
+
+ virt_nvn = dma_to_virt(gdp->dev, (dma_addr_t) hw_nvn);
+
+ for (i = 0; i < GDP_NODE_NB_BANK; i++)
+ if ((virt_nvn != gdp->node_list[i].btm_field) &&
+ (virt_nvn != gdp->node_list[i].top_field))
+ return &gdp->node_list[i];
+
+end:
+ return &gdp->node_list[0];
+}
+
+/**
+ * sti_gdp_get_current_nodes
+ * @layer: GDP layer
+ *
+ * Look for GDP nodes that are currently read by the HW.
+ *
+ * RETURNS:
+ * Pointer to the current GDP node list
+ */
+static
+struct sti_gdp_node_list *sti_gdp_get_current_nodes(struct sti_layer *layer)
+{
+ int hw_nvn;
+ void *virt_nvn;
+ struct sti_gdp *gdp = layer->gdp;
+ int i;
+
+ hw_nvn = readl(gdp->regs + GAM_GDP_NVN_OFFSET);
+ if (!hw_nvn)
+ goto end;
+
+ virt_nvn = dma_to_virt(gdp->dev, (dma_addr_t) hw_nvn);
+
+ for (i = 0; i < GDP_NODE_NB_BANK; i++)
+ if ((virt_nvn == gdp->node_list[i].btm_field) ||
+ (virt_nvn == gdp->node_list[i].top_field))
+ return &gdp->node_list[i];
+
+end:
+ return NULL;
+}
+
+/**
+ * sti_gdp_prepare_layer
+ * @lay: gdp layer
+ * @first_prepare: true if it is the first time this function is called
+ *
+ * Update the free GDP node list according to the layer properties.
+ *
+ * RETURNS:
+ * 0 on success.
+ */
+static int sti_gdp_prepare_layer(void *lay, bool first_prepare)
+{
+ struct sti_layer *layer = (struct sti_layer *)lay;
+ struct sti_gdp_node_list *list;
+ struct sti_gdp_node *top_field, *btm_field;
+ struct drm_display_mode *mode = layer->mode;
+ struct device *dev = layer->gdp->dev;
+ int format, depth, bpp;
+ int rate = mode->clock * 1000;
+ int res;
+ u32 ydo, xdo, yds, xds;
+
+ list = sti_gdp_get_free_nodes(layer);
+ top_field = list->top_field;
+ btm_field = list->btm_field;
+
+ /* Build the top field from layer params */
+ top_field->gam_gdp_agc = GAM_GDP_AGC_FULL_RANGE;
+ top_field->gam_gdp_ctl = WAIT_NEXT_VSYNC;
+ format = sti_gdp_fourcc2format(layer->format);
+ if (format == -1) {
+ DRM_ERROR("Format not supported by GDP %.4s\n",
+ (char *)&layer->format);
+ return 1;
+ }
+ top_field->gam_gdp_ctl |= format;
+ top_field->gam_gdp_ctl |= sti_gdp_get_alpharange(format);
+ top_field->gam_gdp_ppt &= ~GAM_GDP_PPT_IGNORE;
+
+ /* pixel memory location */
+ drm_fb_get_bpp_depth(layer->format, &depth, &bpp);
+ top_field->gam_gdp_pml = (u32) layer->paddr + layer->offsets[0];
+ top_field->gam_gdp_pml += layer->src_x * (bpp >> 3);
+ top_field->gam_gdp_pml += layer->src_y * layer->pitches[0];
+
+ /* input parameters */
+ top_field->gam_gdp_pmp = layer->pitches[0];
+ top_field->gam_gdp_size =
+ clamp_val(layer->src_h, 0, GAM_GDP_SIZE_MAX) << 16 |
+ clamp_val(layer->src_w, 0, GAM_GDP_SIZE_MAX);
+
+ /* output parameters */
+ ydo = sti_vtg_get_line_number(*mode, layer->dst_y);
+ yds = sti_vtg_get_line_number(*mode, layer->dst_y + layer->dst_h - 1);
+ xdo = sti_vtg_get_pixel_number(*mode, layer->dst_x);
+ xds = sti_vtg_get_pixel_number(*mode, layer->dst_x + layer->dst_w - 1);
+ top_field->gam_gdp_vpo = (ydo << 16) | xdo;
+ top_field->gam_gdp_vps = (yds << 16) | xds;
+
+ /* Same content and chained together */
+ memcpy(btm_field, top_field, sizeof(*btm_field));
+ top_field->gam_gdp_nvn = virt_to_dma(dev, btm_field);
+ btm_field->gam_gdp_nvn = virt_to_dma(dev, top_field);
+
+ /* Interlaced mode */
+ if (layer->mode->flags & DRM_MODE_FLAG_INTERLACE)
+ btm_field->gam_gdp_pml = top_field->gam_gdp_pml +
+ layer->pitches[0];
+
+ if (first_prepare) {
+ /* Register gdp callback */
+ if (sti_vtg_register_client(layer->mixer_id,
+ &layer->gdp->vtg_field_nb)) {
+ DRM_ERROR("Cannot register VTG notifier\n");
+ return 1;
+ }
+
+ /* Set and enable gdp clock */
+ if (layer->gdp->clk_pix) {
+ res = clk_set_rate(layer->gdp->clk_pix, rate);
+ if (res < 0) {
+ DRM_ERROR("Cannot set rate (%dHz) for gdp\n",
+ rate);
+ return 1;
+ }
+
+ if (clk_prepare_enable(layer->gdp->clk_pix)) {
+ DRM_ERROR("Failed to prepare/enable gdp\n");
+ return 1;
+ }
+ }
+ }
+
+ return 0;
+}
+
+/**
+ * sti_gdp_commit_layer
+ * @lay: gdp layer
+ *
+ * Update the NVN field of the 'right' field of the current GDP node (being
+ * used by the HW) with the address of the updated ('free') top field GDP node.
+ * - In interlaced mode the 'right' field is the bottom field as we update
+ * frames starting from their top field
+ * - In progressive mode, we update both bottom and top fields which are
+ * equal nodes.
+ * At the next VSYNC, the updated node list will be used by the HW.
+ *
+ * RETURNS:
+ * 0 on success.
+ */
+static int sti_gdp_commit_layer(void *lay)
+{
+ struct sti_layer *layer = (struct sti_layer *)lay;
+ struct sti_gdp_node_list *updated_list = sti_gdp_get_free_nodes(layer);
+ struct sti_gdp_node *updated_top_node = updated_list->top_field;
+ struct sti_gdp_node *updated_btm_node = updated_list->btm_field;
+ struct sti_gdp *gdp = layer->gdp;
+ u32 dma_updated_top = virt_to_dma(gdp->dev, updated_top_node);
+ u32 dma_updated_btm = virt_to_dma(gdp->dev, updated_btm_node);
+ struct sti_gdp_node_list *curr_list = sti_gdp_get_current_nodes(layer);
+
+ dev_dbg(gdp->dev, "Current NVN:0x%X\n",
+ readl(gdp->regs + GAM_GDP_NVN_OFFSET));
+ dev_dbg(gdp->dev, "Posted buff: %lx current buff: %x\n",
+ (unsigned long)layer->paddr,
+ readl(gdp->regs + GAM_GDP_PML_OFFSET));
+
+ if (curr_list == NULL) {
+ /* First update or invalid node should directly write in the
+ * hw register */
+ writel(gdp->is_curr_top == true ?
+ dma_updated_btm : dma_updated_top,
+ gdp->regs + GAM_GDP_NVN_OFFSET);
+ return 0;
+ }
+
+ if (layer->mode->flags & DRM_MODE_FLAG_INTERLACE) {
+ if (gdp->is_curr_top == true) {
+ /* Do not update in the middle of the frame, but
+ * postpone the update after the bottom field has
+ * been displayed */
+ curr_list->btm_field->gam_gdp_nvn = dma_updated_top;
+ } else {
+ /* Direct update to avoid one frame delay */
+ writel(dma_updated_top, gdp->regs + GAM_GDP_NVN_OFFSET);
+ }
+ } else {
+ /* Direct update for progressive to avoid one frame delay */
+ writel(dma_updated_top, gdp->regs + GAM_GDP_NVN_OFFSET);
+ }
+
+ return 0;
+}
+
+/**
+ * sti_gdp_disable_layer
+ * @lay: gdp layer
+ *
+ * Disable a GDP.
+ *
+ * RETURNS:
+ * 0 on success.
+ */
+static int sti_gdp_disable_layer(void *lay)
+{
+ int i;
+ struct sti_layer *layer = (struct sti_layer *)lay;
+ struct sti_gdp *gdp = layer->gdp;
+
+ /* Set the nodes as 'to be ignored on mixer' */
+ for (i = 0; i < GDP_NODE_NB_BANK; i++) {
+ gdp->node_list[i].top_field->gam_gdp_ppt |= GAM_GDP_PPT_IGNORE;
+ gdp->node_list[i].btm_field->gam_gdp_ppt |= GAM_GDP_PPT_IGNORE;
+ }
+
+ if (sti_vtg_unregister_client(layer->mixer_id, &gdp->vtg_field_nb))
+ DRM_DEBUG_DRIVER("Warning: cannot unregister VTG notifier\n");
+
+ if (gdp->clk_pix)
+ clk_disable_unprepare(gdp->clk_pix);
+
+ return 0;
+}
+
+/**
+ * sti_gdp_field_cb
+ * @nb: notifier block
+ * @event: event message
+ * @data: private data
+ *
+ * Handle VTG top field and bottom field event.
+ *
+ * RETURNS:
+ * 0 on success.
+ */
+int sti_gdp_field_cb(struct notifier_block *nb,
+ unsigned long event, void *data)
+{
+ struct sti_gdp *gdp = container_of(nb, struct sti_gdp, vtg_field_nb);
+
+ switch (event) {
+ case VTG_TOP_FIELD_EVENT:
+ gdp->is_curr_top = true;
+ break;
+ case VTG_BOTTOM_FIELD_EVENT:
+ gdp->is_curr_top = false;
+ break;
+ default:
+ DRM_ERROR("unsupported event: %lu\n", event);
+ break;
+ }
+
+ return 0;
+}
+
+/**
+ * sti_gdp_create
+ * @dev: device
+ * @id: gdp id
+ * @baseaddr: IO addr
+ *
+ * Create a gdp object. Allocate memory and initialize parameters.
+ *
+ *
+ * RETURNS:
+ * Pointer to the created gdp object.
+ */
+struct sti_gdp *sti_gdp_create(struct device *dev, int id,
+ void __iomem *baseaddr)
+{
+ struct sti_gdp *gdp;
+ struct device_node *np = dev->of_node;
+ dma_addr_t dma;
+ void *base;
+ int i, size;
+
+ gdp = devm_kzalloc(dev, sizeof(*gdp), GFP_KERNEL);
+ if (!gdp) {
+ DRM_ERROR("Failed to allocate memory for GDP\n");
+ return NULL;
+ }
+
+ /* Allocate all the nodes within a single memory page */
+ size = sizeof(struct sti_gdp_node) *
+ GDP_NODE_PER_FIELD * GDP_NODE_NB_BANK;
+
+ base = dma_alloc_writecombine(dev, size, &dma, GFP_KERNEL | GFP_DMA);
+ if (!base) {
+ DRM_ERROR("Failed to allocate memory for GDP node\n");
+ goto mem_err;
+ }
+ memset(base, 0, size);
+
+ for (i = 0; i < GDP_NODE_NB_BANK; i++) {
+ if (virt_to_dma(dev, base) & 0xF) {
+ DRM_ERROR("Mem alignment failed\n");
+ goto mem_err;
+ }
+ gdp->node_list[i].top_field = base;
+ DRM_DEBUG_DRIVER("node[%d].top_field=%p\n", i, base);
+ base += sizeof(struct sti_gdp_node);
+
+ if (virt_to_dma(dev, base) & 0xF) {
+ DRM_ERROR("Mem alignment failed\n");
+ goto mem_err;
+ }
+ gdp->node_list[i].btm_field = base;
+ DRM_DEBUG_DRIVER("node[%d].btm_field=%p\n", i, base);
+ base += sizeof(struct sti_gdp_node);
+ }
+
+ gdp->dev = dev;
+ gdp->regs = baseaddr;
+ gdp->get_formats = sti_gdp_get_formats;
+ gdp->get_nb_formats = sti_gdp_get_nb_formats;
+ gdp->prepare = sti_gdp_prepare_layer;
+ gdp->commit = sti_gdp_commit_layer;
+ gdp->disable = sti_gdp_disable_layer;
+ gdp->vtg_field_nb.notifier_call = sti_gdp_field_cb;
+
+ if (of_device_is_compatible(np, "st,stih407-compositor")) {
+ /* GDP of STiH407 chip have its own pixel clock */
+ char *clk_name;
+
+ switch (id) {
+ case STI_GDP_0:
+ clk_name = "pix_gdp1";
+ break;
+ case STI_GDP_1:
+ clk_name = "pix_gdp2";
+ break;
+ case STI_GDP_2:
+ clk_name = "pix_gdp3";
+ break;
+ case STI_GDP_3:
+ clk_name = "pix_gdp4";
+ break;
+ default:
+ DRM_ERROR("GDP id not recognized\n");
+ goto err_clk_pix_gdp;
+ }
+
+ gdp->clk_pix = devm_clk_get(dev, clk_name);
+ if (IS_ERR(gdp->clk_pix)) {
+ DRM_ERROR("Cannot get %s clock\n", clk_name);
+ goto err_clk_pix_gdp;
+ }
+ }
+
+ return gdp;
+
+err_clk_pix_gdp:
+mem_err:
+ devm_kfree(dev, gdp);
+ return NULL;
+}
diff --git a/drivers/gpu/drm/sti/sti_gdp.h b/drivers/gpu/drm/sti/sti_gdp.h
new file mode 100644
index 0000000..4f7f40b
--- /dev/null
+++ b/drivers/gpu/drm/sti/sti_gdp.h
@@ -0,0 +1,73 @@
+/*
+ * Copyright (C) STMicroelectronics SA 2013
+ * Authors: Benjamin Gaignard <benjamin.gaignard@xxxxxx>
+ * Fabien Dessenne <fabien.dessenne@xxxxxx>
+ * for STMicroelectronics.
+ * License terms: GNU General Public License (GPL), version 2
+ */
+
+#ifndef _STI_GDP_H_
+#define _STI_GDP_H_
+
+#include <linux/types.h>
+
+#define GDP_NODE_NB_BANK 2
+#define GDP_NODE_PER_FIELD 2
+
+struct sti_gdp_node {
+ u32 gam_gdp_ctl;
+ u32 gam_gdp_agc;
+ u32 reserved1;
+ u32 gam_gdp_vpo;
+ u32 gam_gdp_vps;
+ u32 gam_gdp_pml;
+ u32 gam_gdp_pmp;
+ u32 gam_gdp_size;
+ u32 reserved2;
+ u32 gam_gdp_nvn;
+ u32 gam_gdp_key1;
+ u32 gam_gdp_key2;
+ u32 reserved3;
+ u32 gam_gdp_ppt;
+ u32 reserved4;
+ u32 gam_gdp_cml;
+};
+
+struct sti_gdp_node_list {
+ struct sti_gdp_node *top_field;
+ struct sti_gdp_node *btm_field;
+};
+
+/*
+ * STI GDP structure
+ *
+ * @device: driver device
+ * @regs: subdevice register
+ * @clk_pix: pixel clock for the current gdp
+ * @vtg_field_nb: callback for VTG FIELD (top or bottom) notification
+ * @is_curr_top: true if the current node processed is the top field
+ * @get_formats: get GDP supported formats
+ * @get_nb_formats: get number of format supported
+ * @prepare: prepare GDP before rendering
+ * @commit: set GDP for rendering
+ * @disable: disable GDP
+ * @node_list: array of node list
+ */
+struct sti_gdp {
+ struct device *dev;
+ void __iomem *regs;
+ struct clk *clk_pix;
+ struct notifier_block vtg_field_nb;
+ bool is_curr_top;
+ const uint32_t* (*get_formats)(void);
+ int (*get_nb_formats)(void);
+ int (*prepare)(void *layer, bool first_prepare);
+ int (*commit)(void *layer);
+ int (*disable)(void *layer);
+ struct sti_gdp_node_list node_list[GDP_NODE_NB_BANK];
+};
+
+struct sti_gdp *sti_gdp_create(struct device *dev, int id,
+ void __iomem *baseaddr);
+
+#endif
diff --git a/drivers/gpu/drm/sti/sti_layer.h b/drivers/gpu/drm/sti/sti_layer.h
index ed8386a..45cd1ea 100644
--- a/drivers/gpu/drm/sti/sti_layer.h
+++ b/drivers/gpu/drm/sti/sti_layer.h
@@ -10,6 +10,7 @@
#define _STI_LAYER_H_
#include <drm/drmP.h>
+#include "sti_gdp.h"
#define to_sti_layer(x) container_of(x, struct sti_layer, plane)
@@ -67,6 +68,7 @@ struct sti_fps_info {
* @offsets: offset of 'planes'
* @paddr: physical address of the input buffer
* @fps_info: frame per second info
+ * @gdp: related GDP (if the layer is a GDP)
*/
struct sti_layer {
struct drm_plane plane;
@@ -74,6 +76,7 @@ struct sti_layer {
struct drm_display_mode *mode;
enum sti_layer_desc desc;
int zorder;
+ int mixer_id;
bool enabled;
int src_x, src_y;
int src_w, src_h;
@@ -84,12 +87,14 @@ struct sti_layer {
int offsets[4];
dma_addr_t paddr;
struct sti_fps_info fps_info;
+ struct sti_gdp *gdp;
};
struct sti_layer *sti_layer_create(struct device *dev, int desc,
void __iomem *baseaddr);
int sti_layer_prepare(struct sti_layer *layer, struct drm_framebuffer *fb,
struct drm_display_mode *mode,
+ int mixer_id,
int dest_x, int dest_y,
int dest_w, int dest_h,
int src_x, int src_y,
--
1.9.1
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