Re: [PATCH v3 4/6] drm/sprd: add Unisoc's drm display controller driver
From: Daniel Vetter
Date: Wed Feb 03 2021 - 09:25:27 EST
On Tue, Jan 05, 2021 at 09:46:05PM +0800, Kevin Tang wrote:
> Adds DPU(Display Processor Unit) support for the Unisoc's display subsystem.
> It's support multi planes, scaler, rotation, PQ(Picture Quality) and more.
>
> Cc: Orson Zhai <orsonzhai@xxxxxxxxx>
> Cc: Chunyan Zhang <zhang.lyra@xxxxxxxxx>
> Signed-off-by: Kevin Tang <kevin.tang@xxxxxxxxxx>
>
> v2:
> - Use drm_xxx to replace all DRM_XXX.
> - Use kzalloc to replace devm_kzalloc for sprd_dpu structure init.
>
> v3:
> - Remove dpu_layer stuff layer and commit layers by aotmic_update
Ok noticed one more, see below.
> ---
> drivers/gpu/drm/sprd/Kconfig | 1 +
> drivers/gpu/drm/sprd/Makefile | 4 +-
> drivers/gpu/drm/sprd/sprd_dpu.c | 985 ++++++++++++++++++++++++++++++++++++++++
> drivers/gpu/drm/sprd/sprd_dpu.h | 120 +++++
> drivers/gpu/drm/sprd/sprd_drm.c | 1 +
> drivers/gpu/drm/sprd/sprd_drm.h | 2 +
> 6 files changed, 1111 insertions(+), 2 deletions(-)
> create mode 100644 drivers/gpu/drm/sprd/sprd_dpu.c
> create mode 100644 drivers/gpu/drm/sprd/sprd_dpu.h
>
> diff --git a/drivers/gpu/drm/sprd/Kconfig b/drivers/gpu/drm/sprd/Kconfig
> index 6e80cc9..9b4ef9a 100644
> --- a/drivers/gpu/drm/sprd/Kconfig
> +++ b/drivers/gpu/drm/sprd/Kconfig
> @@ -3,6 +3,7 @@ config DRM_SPRD
> depends on ARCH_SPRD || COMPILE_TEST
> depends on DRM && OF
> select DRM_KMS_HELPER
> + select VIDEOMODE_HELPERS
> select DRM_GEM_CMA_HELPER
> select DRM_KMS_CMA_HELPER
> select DRM_MIPI_DSI
> diff --git a/drivers/gpu/drm/sprd/Makefile b/drivers/gpu/drm/sprd/Makefile
> index 86d95d9..6c25bfa 100644
> --- a/drivers/gpu/drm/sprd/Makefile
> +++ b/drivers/gpu/drm/sprd/Makefile
> @@ -1,5 +1,5 @@
> # SPDX-License-Identifier: GPL-2.0
>
> -subdir-ccflags-y += -I$(srctree)/$(src)
> +obj-y := sprd_drm.o \
> + sprd_dpu.o
>
> -obj-y := sprd_drm.o
> diff --git a/drivers/gpu/drm/sprd/sprd_dpu.c b/drivers/gpu/drm/sprd/sprd_dpu.c
> new file mode 100644
> index 0000000..d562d44
> --- /dev/null
> +++ b/drivers/gpu/drm/sprd/sprd_dpu.c
> @@ -0,0 +1,985 @@
> +// SPDX-License-Identifier: GPL-2.0
> +/*
> + * Copyright (C) 2020 Unisoc Inc.
> + */
> +
> +#include <linux/component.h>
> +#include <linux/delay.h>
> +#include <linux/dma-buf.h>
> +#include <linux/io.h>
> +#include <linux/module.h>
> +#include <linux/of.h>
> +#include <linux/of_address.h>
> +#include <linux/of_device.h>
> +#include <linux/of_irq.h>
> +#include <linux/wait.h>
> +#include <linux/workqueue.h>
> +
> +#include <drm/drm_atomic_helper.h>
> +#include <drm/drm_crtc_helper.h>
> +#include <drm/drm_fb_cma_helper.h>
> +#include <drm/drm_gem_cma_helper.h>
> +#include <drm/drm_gem_framebuffer_helper.h>
> +#include <drm/drm_plane_helper.h>
> +
> +#include "sprd_drm.h"
> +#include "sprd_dpu.h"
> +
> +/* Global control registers */
> +#define REG_DPU_CTRL 0x04
> +#define REG_DPU_CFG0 0x08
> +#define REG_PANEL_SIZE 0x20
> +#define REG_BLEND_SIZE 0x24
> +#define REG_BG_COLOR 0x2C
> +
> +/* Layer0 control registers */
> +#define REG_LAY_BASE_ADDR0 0x30
> +#define REG_LAY_BASE_ADDR1 0x34
> +#define REG_LAY_BASE_ADDR2 0x38
> +#define REG_LAY_CTRL 0x40
> +#define REG_LAY_SIZE 0x44
> +#define REG_LAY_PITCH 0x48
> +#define REG_LAY_POS 0x4C
> +#define REG_LAY_ALPHA 0x50
> +#define REG_LAY_CROP_START 0x5C
> +
> +/* Interrupt control registers */
> +#define REG_DPU_INT_EN 0x1E0
> +#define REG_DPU_INT_CLR 0x1E4
> +#define REG_DPU_INT_STS 0x1E8
> +
> +/* DPI control registers */
> +#define REG_DPI_CTRL 0x1F0
> +#define REG_DPI_H_TIMING 0x1F4
> +#define REG_DPI_V_TIMING 0x1F8
> +
> +/* MMU control registers */
> +#define REG_MMU_EN 0x800
> +#define REG_MMU_VPN_RANGE 0x80C
> +#define REG_MMU_VAOR_ADDR_RD 0x818
> +#define REG_MMU_VAOR_ADDR_WR 0x81C
> +#define REG_MMU_INV_ADDR_RD 0x820
> +#define REG_MMU_INV_ADDR_WR 0x824
> +#define REG_MMU_PPN1 0x83C
> +#define REG_MMU_RANGE1 0x840
> +#define REG_MMU_PPN2 0x844
> +#define REG_MMU_RANGE2 0x848
> +
> +/* Global control bits */
> +#define BIT_DPU_RUN BIT(0)
> +#define BIT_DPU_STOP BIT(1)
> +#define BIT_DPU_REG_UPDATE BIT(2)
> +#define BIT_DPU_IF_EDPI BIT(0)
> +
> +/* Layer control bits */
> +#define BIT_DPU_LAY_EN BIT(0)
> +#define BIT_DPU_LAY_LAYER_ALPHA (0x01 << 2)
> +#define BIT_DPU_LAY_COMBO_ALPHA (0x02 << 2)
> +#define BIT_DPU_LAY_FORMAT_YUV422_2PLANE (0x00 << 4)
> +#define BIT_DPU_LAY_FORMAT_YUV420_2PLANE (0x01 << 4)
> +#define BIT_DPU_LAY_FORMAT_YUV420_3PLANE (0x02 << 4)
> +#define BIT_DPU_LAY_FORMAT_ARGB8888 (0x03 << 4)
> +#define BIT_DPU_LAY_FORMAT_RGB565 (0x04 << 4)
> +#define BIT_DPU_LAY_DATA_ENDIAN_B0B1B2B3 (0x00 << 8)
> +#define BIT_DPU_LAY_DATA_ENDIAN_B3B2B1B0 (0x01 << 8)
> +#define BIT_DPU_LAY_NO_SWITCH (0x00 << 10)
> +#define BIT_DPU_LAY_RB_OR_UV_SWITCH (0x01 << 10)
> +#define BIT_DPU_LAY_MODE_BLEND_NORMAL (0x00 << 16)
> +#define BIT_DPU_LAY_MODE_BLEND_PREMULT (0x01 << 16)
> +
> +/* Interrupt control & status bits */
> +#define BIT_DPU_INT_DONE BIT(0)
> +#define BIT_DPU_INT_TE BIT(1)
> +#define BIT_DPU_INT_ERR BIT(2)
> +#define BIT_DPU_INT_UPDATE_DONE BIT(4)
> +#define BIT_DPU_INT_VSYNC BIT(5)
> +#define BIT_DPU_INT_MMU_VAOR_RD BIT(16)
> +#define BIT_DPU_INT_MMU_VAOR_WR BIT(17)
> +#define BIT_DPU_INT_MMU_INV_RD BIT(18)
> +#define BIT_DPU_INT_MMU_INV_WR BIT(19)
> +
> +/* DPI control bits */
> +#define BIT_DPU_EDPI_TE_EN BIT(8)
> +#define BIT_DPU_EDPI_FROM_EXTERNAL_PAD BIT(10)
> +#define BIT_DPU_DPI_HALT_EN BIT(16)
> +
> +static const u32 primary_fmts[] = {
> + DRM_FORMAT_XRGB8888,
> + DRM_FORMAT_XBGR8888,
> + DRM_FORMAT_ARGB8888,
> + DRM_FORMAT_ABGR8888,
> + DRM_FORMAT_RGBA8888,
> + DRM_FORMAT_BGRA8888,
> + DRM_FORMAT_RGBX8888,
> + DRM_FORMAT_RGB565,
> + DRM_FORMAT_BGR565,
> + DRM_FORMAT_NV12,
> + DRM_FORMAT_NV21,
> + DRM_FORMAT_NV16,
> + DRM_FORMAT_NV61,
> + DRM_FORMAT_YUV420,
> + DRM_FORMAT_YVU420,
> +};
> +
> +struct sprd_plane {
> + struct drm_plane plane;
> + u32 index;
> +};
> +
> +static inline struct sprd_plane *to_sprd_plane(struct drm_plane *plane)
> +{
> + return container_of(plane, struct sprd_plane, plane);
> +}
> +
> +static u32 check_mmu_isr(struct sprd_dpu *dpu, u32 reg_val)
> +{
> + struct dpu_context *ctx = &dpu->ctx;
> + u32 mmu_mask = BIT_DPU_INT_MMU_VAOR_RD |
> + BIT_DPU_INT_MMU_VAOR_WR |
> + BIT_DPU_INT_MMU_INV_RD |
> + BIT_DPU_INT_MMU_INV_WR;
> + u32 val = reg_val & mmu_mask;
> + int i;
> +
> + if (val) {
> + drm_err(dpu->drm, "--- iommu interrupt err: 0x%04x ---\n", val);
> +
> + if (val & BIT_DPU_INT_MMU_INV_RD)
> + drm_err(dpu->drm, "iommu invalid read error, addr: 0x%08x\n",
> + readl(ctx->base + REG_MMU_INV_ADDR_RD));
> + if (val & BIT_DPU_INT_MMU_INV_WR)
> + drm_err(dpu->drm, "iommu invalid write error, addr: 0x%08x\n",
> + readl(ctx->base + REG_MMU_INV_ADDR_WR));
> + if (val & BIT_DPU_INT_MMU_VAOR_RD)
> + drm_err(dpu->drm, "iommu va out of range read error, addr: 0x%08x\n",
> + readl(ctx->base + REG_MMU_VAOR_ADDR_RD));
> + if (val & BIT_DPU_INT_MMU_VAOR_WR)
> + drm_err(dpu->drm, "iommu va out of range write error, addr: 0x%08x\n",
> + readl(ctx->base + REG_MMU_VAOR_ADDR_WR));
> +
> + for (i = 0; i < 8; i++) {
> + reg_val = layer_reg_rd(ctx, REG_LAY_CTRL, i);
> + if (reg_val & 0x1)
> + drm_info(dpu->drm, "layer%d: 0x%08x 0x%08x 0x%08x ctrl: 0x%08x\n", i,
> + layer_reg_rd(ctx, REG_LAY_BASE_ADDR0, i),
> + layer_reg_rd(ctx, REG_LAY_BASE_ADDR1, i),
> + layer_reg_rd(ctx, REG_LAY_BASE_ADDR2, i),
> + layer_reg_rd(ctx, REG_LAY_CTRL, i));
> + }
> + }
> +
> + return val;
> +}
> +
> +static int dpu_wait_stop_done(struct sprd_dpu *dpu)
> +{
> + struct dpu_context *ctx = &dpu->ctx;
> + int rc;
> +
> + if (ctx->stopped)
> + return 0;
> +
> + rc = wait_event_interruptible_timeout(ctx->wait_queue, ctx->evt_stop,
> + msecs_to_jiffies(500));
> + ctx->evt_stop = false;
> +
> + ctx->stopped = true;
> +
> + if (!rc) {
> + drm_err(dpu->drm, "dpu wait for stop done time out!\n");
> + return -ETIMEDOUT;
> + }
> +
> + return 0;
> +}
> +
> +static int dpu_wait_update_done(struct sprd_dpu *dpu)
> +{
> + struct dpu_context *ctx = &dpu->ctx;
> + int rc;
> +
> + ctx->evt_update = false;
> +
> + rc = wait_event_interruptible_timeout(ctx->wait_queue, ctx->evt_update,
> + msecs_to_jiffies(500));
> +
> + if (!rc) {
> + drm_err(dpu->drm, "dpu wait for reg update done time out!\n");
> + return -ETIMEDOUT;
> + }
> +
> + return 0;
> +}
> +
> +static u32 drm_format_to_dpu(struct drm_framebuffer *fb)
> +{
> + u32 format = 0;
> +
> + switch (fb->format->format) {
> + case DRM_FORMAT_BGRA8888:
> + /* BGRA8888 -> ARGB8888 */
> + format |= BIT_DPU_LAY_DATA_ENDIAN_B3B2B1B0;
> + format |= BIT_DPU_LAY_FORMAT_ARGB8888;
> + break;
> + case DRM_FORMAT_RGBX8888:
> + case DRM_FORMAT_RGBA8888:
> + /* RGBA8888 -> ABGR8888 */
> + format |= BIT_DPU_LAY_DATA_ENDIAN_B3B2B1B0;
> + /* fallthrough */
> + case DRM_FORMAT_ABGR8888:
> + /* RB switch */
> + format |= BIT_DPU_LAY_RB_OR_UV_SWITCH;
> + /* fallthrough */
> + case DRM_FORMAT_ARGB8888:
> + format |= BIT_DPU_LAY_FORMAT_ARGB8888;
> + break;
> + case DRM_FORMAT_XBGR8888:
> + /* RB switch */
> + format |= BIT_DPU_LAY_RB_OR_UV_SWITCH;
> + /* fallthrough */
> + case DRM_FORMAT_XRGB8888:
> + format |= BIT_DPU_LAY_FORMAT_ARGB8888;
> + break;
> + case DRM_FORMAT_BGR565:
> + /* RB switch */
> + format |= BIT_DPU_LAY_RB_OR_UV_SWITCH;
> + /* fallthrough */
> + case DRM_FORMAT_RGB565:
> + format |= BIT_DPU_LAY_FORMAT_RGB565;
> + break;
> + case DRM_FORMAT_NV12:
> + /* 2-Lane: Yuv420 */
> + format |= BIT_DPU_LAY_FORMAT_YUV420_2PLANE;
> + /* Y endian */
> + format |= BIT_DPU_LAY_DATA_ENDIAN_B0B1B2B3;
> + /* UV endian */
> + format |= BIT_DPU_LAY_NO_SWITCH;
> + break;
> + case DRM_FORMAT_NV21:
> + /* 2-Lane: Yuv420 */
> + format |= BIT_DPU_LAY_FORMAT_YUV420_2PLANE;
> + /* Y endian */
> + format |= BIT_DPU_LAY_DATA_ENDIAN_B0B1B2B3;
> + /* UV endian */
> + format |= BIT_DPU_LAY_RB_OR_UV_SWITCH;
> + break;
> + case DRM_FORMAT_NV16:
> + /* 2-Lane: Yuv422 */
> + format |= BIT_DPU_LAY_FORMAT_YUV422_2PLANE;
> + /* Y endian */
> + format |= BIT_DPU_LAY_DATA_ENDIAN_B3B2B1B0;
> + /* UV endian */
> + format |= BIT_DPU_LAY_RB_OR_UV_SWITCH;
> + break;
> + case DRM_FORMAT_NV61:
> + /* 2-Lane: Yuv422 */
> + format |= BIT_DPU_LAY_FORMAT_YUV422_2PLANE;
> + /* Y endian */
> + format |= BIT_DPU_LAY_DATA_ENDIAN_B0B1B2B3;
> + /* UV endian */
> + format |= BIT_DPU_LAY_NO_SWITCH;
> + break;
> + case DRM_FORMAT_YUV420:
> + format |= BIT_DPU_LAY_FORMAT_YUV420_3PLANE;
> + /* Y endian */
> + format |= BIT_DPU_LAY_DATA_ENDIAN_B0B1B2B3;
> + /* UV endian */
> + format |= BIT_DPU_LAY_NO_SWITCH;
> + break;
> + case DRM_FORMAT_YVU420:
> + format |= BIT_DPU_LAY_FORMAT_YUV420_3PLANE;
> + /* Y endian */
> + format |= BIT_DPU_LAY_DATA_ENDIAN_B0B1B2B3;
> + /* UV endian */
> + format |= BIT_DPU_LAY_RB_OR_UV_SWITCH;
> + break;
> + default:
> + break;
> + }
> +
> + return format;
> +}
> +
> +static u32 drm_rotation_to_dpu(struct drm_plane_state *state)
> +{
> + u32 rotation;
> +
> + switch (state->rotation) {
> + default:
> + case DRM_MODE_ROTATE_0:
> + rotation = DPU_LAYER_ROTATION_0;
> + break;
> + case DRM_MODE_ROTATE_90:
> + rotation = DPU_LAYER_ROTATION_90;
> + break;
> + case DRM_MODE_ROTATE_180:
> + rotation = DPU_LAYER_ROTATION_180;
> + break;
> + case DRM_MODE_ROTATE_270:
> + rotation = DPU_LAYER_ROTATION_270;
> + break;
> + case DRM_MODE_REFLECT_Y:
> + rotation = DPU_LAYER_ROTATION_180_M;
> + break;
> + case (DRM_MODE_REFLECT_Y | DRM_MODE_ROTATE_90):
> + rotation = DPU_LAYER_ROTATION_90_M;
> + break;
> + case DRM_MODE_REFLECT_X:
> + rotation = DPU_LAYER_ROTATION_0_M;
> + break;
> + case (DRM_MODE_REFLECT_X | DRM_MODE_ROTATE_90):
> + rotation = DPU_LAYER_ROTATION_270_M;
> + break;
> + }
> +
> + return rotation;
> +}
> +
> +static u32 drm_blend_to_dpu(struct drm_plane_state *state)
> +{
> + u32 blend = 0;
> +
> + switch (state->pixel_blend_mode) {
> + case DRM_MODE_BLEND_COVERAGE:
> + /* alpha mode select - combo alpha */
> + blend |= BIT_DPU_LAY_COMBO_ALPHA;
> + /* Normal mode */
> + blend |= BIT_DPU_LAY_MODE_BLEND_NORMAL;
> + break;
> + case DRM_MODE_BLEND_PREMULTI:
> + /* alpha mode select - combo alpha */
> + blend |= BIT_DPU_LAY_COMBO_ALPHA;
> + /* Pre-mult mode */
> + blend |= BIT_DPU_LAY_MODE_BLEND_PREMULT;
> + break;
> + case DRM_MODE_BLEND_PIXEL_NONE:
> + default:
> + /* don't do blending, maybe RGBX */
> + /* alpha mode select - layer alpha */
> + blend |= BIT_DPU_LAY_LAYER_ALPHA;
> + break;
> + }
> +
> + return blend;
> +}
> +
> +static void sprd_dpu_layer(struct sprd_dpu *dpu, struct sprd_plane *plane,
> + struct drm_plane_state *state)
> +{
> + struct dpu_context *ctx = &dpu->ctx;
> + struct drm_gem_cma_object *cma_obj;
> + const struct drm_format_info *info;
> + struct drm_framebuffer *fb = state->fb;
> + u32 addr, size, offset, pitch, blend, format, rotation;
> + u32 src_x = state->src_x >> 16;
> + u32 src_y = state->src_y >> 16;
> + u32 src_w = state->src_w >> 16;
> + u32 src_h = state->src_h >> 16;
> + u32 dst_x = state->crtc_x;
> + u32 dst_y = state->crtc_y;
> + u32 alpha = state->alpha;
> + int i;
> +
> + offset = (dst_x & 0xffff) | (dst_y << 16);
> + size = (src_w & 0xffff) | (src_h << 16);
> +
> + for (i = 0; i < fb->format->num_planes; i++) {
> + cma_obj = drm_fb_cma_get_gem_obj(fb, i);
> + addr = cma_obj->paddr + fb->offsets[i];
> +
> + if (i == 0)
> + layer_reg_wr(ctx, REG_LAY_BASE_ADDR0, addr, plane->index);
> + else if (i == 1)
> + layer_reg_wr(ctx, REG_LAY_BASE_ADDR1, addr, plane->index);
> + else
> + layer_reg_wr(ctx, REG_LAY_BASE_ADDR2, addr, plane->index);
> + }
> +
> + info = drm_format_info(fb->format->format);
> + if (fb->format->num_planes == 3) {
> + /* UV pitch is 1/2 of Y pitch */
> + pitch = (fb->pitches[0] / info->cpp[0]) |
> + (fb->pitches[0] / info->cpp[0] << 15);
> + } else {
> + pitch = fb->pitches[0] / info->cpp[0];
> + }
> +
> + layer_reg_wr(ctx, REG_LAY_POS, offset, plane->index);
> + layer_reg_wr(ctx, REG_LAY_SIZE, size, plane->index);
> + layer_reg_wr(ctx, REG_LAY_CROP_START,
> + src_y << 16 | src_x, plane->index);
> + layer_reg_wr(ctx, REG_LAY_ALPHA, alpha, plane->index);
> + layer_reg_wr(ctx, REG_LAY_PITCH, pitch, plane->index);
> +
> + format = drm_format_to_dpu(fb);
> + blend = drm_blend_to_dpu(state);
> + rotation = drm_rotation_to_dpu(state);
> +
> + layer_reg_wr(ctx, REG_LAY_CTRL, BIT_DPU_LAY_EN |
> + format |
> + blend |
> + rotation << 20,
> + plane->index);
> +}
> +
> +static void sprd_dpu_flip(struct sprd_dpu *dpu)
> +{
> + struct dpu_context *ctx = &dpu->ctx;
> + u32 reg_val;
> +
> + /*
> + * Make sure the dpu is in stop status. DPU has no shadow
> + * registers in EDPI mode. So the config registers can only be
> + * updated in the rising edge of DPU_RUN bit.
> + */
> + if (ctx->if_type == SPRD_DPU_IF_EDPI)
> + dpu_wait_stop_done(dpu);
> +
> + /* update trigger and wait */
> + if (ctx->if_type == SPRD_DPU_IF_DPI) {
> + if (!ctx->stopped) {
> + dpu_reg_set(ctx, REG_DPU_CTRL, BIT_DPU_REG_UPDATE);
> + dpu_wait_update_done(dpu);
> + }
> +
> + dpu_reg_set(ctx, REG_DPU_INT_EN, BIT_DPU_INT_ERR);
> + } else if (ctx->if_type == SPRD_DPU_IF_EDPI) {
> + dpu_reg_set(ctx, REG_DPU_CTRL, BIT_DPU_RUN);
> +
> + ctx->stopped = false;
> + }
> +
> + /*
> + * If the following interrupt was disabled in isr,
> + * re-enable it.
> + */
> + reg_val = BIT_DPU_INT_MMU_VAOR_RD |
> + BIT_DPU_INT_MMU_VAOR_WR |
> + BIT_DPU_INT_MMU_INV_RD |
> + BIT_DPU_INT_MMU_INV_WR;
> + dpu_reg_set(ctx, REG_DPU_INT_EN, reg_val);
> +}
> +
> +static void sprd_dpu_init(struct sprd_dpu *dpu)
> +{
> + struct dpu_context *ctx = &dpu->ctx;
> + u32 reg_val, size;
> +
> + writel(0x00, ctx->base + REG_BG_COLOR);
> +
> + size = (ctx->vm.vactive << 16) | ctx->vm.hactive;
> + writel(size, ctx->base + REG_PANEL_SIZE);
> + writel(size, ctx->base + REG_BLEND_SIZE);
> +
> + writel(0x00, ctx->base + REG_MMU_EN);
> + writel(0x00, ctx->base + REG_MMU_PPN1);
> + writel(0xffff, ctx->base + REG_MMU_RANGE1);
> + writel(0x00, ctx->base + REG_MMU_PPN2);
> + writel(0xffff, ctx->base + REG_MMU_RANGE2);
> + writel(0x1ffff, ctx->base + REG_MMU_VPN_RANGE);
> +}
> +
> +static void sprd_dpu_fini(struct sprd_dpu *dpu)
> +{
> + struct dpu_context *ctx = &dpu->ctx;
> +
> + writel(0x00, ctx->base + REG_DPU_INT_EN);
> + writel(0xff, ctx->base + REG_DPU_INT_CLR);
> +}
> +
> +static void sprd_dpi_init(struct sprd_dpu *dpu)
> +{
> + struct dpu_context *ctx = &dpu->ctx;
> + u32 int_mask = 0;
> + u32 reg_val;
> +
> + if (ctx->if_type == SPRD_DPU_IF_DPI) {
> + /* use dpi as interface */
> + dpu_reg_clr(ctx, REG_DPU_CFG0, BIT_DPU_IF_EDPI);
> + /* disable Halt function for SPRD DSI */
> + dpu_reg_clr(ctx, REG_DPI_CTRL, BIT_DPU_DPI_HALT_EN);
> + /* select te from external pad */
> + dpu_reg_set(ctx, REG_DPI_CTRL, BIT_DPU_EDPI_FROM_EXTERNAL_PAD);
> +
> + /* set dpi timing */
> + reg_val = ctx->vm.hsync_len << 0 |
> + ctx->vm.hback_porch << 8 |
> + ctx->vm.hfront_porch << 20;
> + writel(reg_val, ctx->base + REG_DPI_H_TIMING);
> +
> + reg_val = ctx->vm.vsync_len << 0 |
> + ctx->vm.vback_porch << 8 |
> + ctx->vm.vfront_porch << 20;
> + writel(reg_val, ctx->base + REG_DPI_V_TIMING);
> +
> + if (ctx->vm.vsync_len + ctx->vm.vback_porch < 32)
> + drm_warn(dpu->drm, "Warning: (vsync + vbp) < 32, "
> + "underflow risk!\n");
> +
> + /* enable dpu update done INT */
> + int_mask |= BIT_DPU_INT_UPDATE_DONE;
> + /* enable dpu done INT */
> + int_mask |= BIT_DPU_INT_DONE;
> + /* enable dpu dpi vsync */
> + int_mask |= BIT_DPU_INT_VSYNC;
> + /* enable dpu TE INT */
> + int_mask |= BIT_DPU_INT_TE;
> + /* enable underflow err INT */
> + int_mask |= BIT_DPU_INT_ERR;
> + } else if (ctx->if_type == SPRD_DPU_IF_EDPI) {
> + /* use edpi as interface */
> + dpu_reg_set(ctx, REG_DPU_CFG0, BIT_DPU_IF_EDPI);
> + /* use external te */
> + dpu_reg_set(ctx, REG_DPI_CTRL, BIT_DPU_EDPI_FROM_EXTERNAL_PAD);
> + /* enable te */
> + dpu_reg_set(ctx, REG_DPI_CTRL, BIT_DPU_EDPI_TE_EN);
> +
> + /* enable stop done INT */
> + int_mask |= BIT_DPU_INT_DONE;
> + /* enable TE INT */
> + int_mask |= BIT_DPU_INT_TE;
> + }
> +
> + /* enable iommu va out of range read error INT */
> + int_mask |= BIT_DPU_INT_MMU_VAOR_RD;
> + /* enable iommu va out of range write error INT */
> + int_mask |= BIT_DPU_INT_MMU_VAOR_WR;
> + /* enable iommu invalid read error INT */
> + int_mask |= BIT_DPU_INT_MMU_INV_RD;
> + /* enable iommu invalid write error INT */
> + int_mask |= BIT_DPU_INT_MMU_INV_WR;
> +
> + writel(int_mask, ctx->base + REG_DPU_INT_EN);
> +}
> +
> +void sprd_dpu_run(struct sprd_dpu *dpu)
> +{
> + struct dpu_context *ctx = &dpu->ctx;
> +
> + dpu_reg_set(ctx, REG_DPU_CTRL, BIT_DPU_RUN);
> +
> + ctx->stopped = false;
> +}
> +
> +void sprd_dpu_stop(struct sprd_dpu *dpu)
> +{
> + struct dpu_context *ctx = &dpu->ctx;
> +
> + if (ctx->if_type == SPRD_DPU_IF_DPI)
> + dpu_reg_set(ctx, REG_DPU_CTRL, BIT_DPU_STOP);
> +
> + dpu_wait_stop_done(dpu);
> +}
> +
> +static int sprd_plane_atomic_check(struct drm_plane *plane,
> + struct drm_plane_state *state)
> +{
> + struct drm_framebuffer *fb = state->fb;
> + struct drm_crtc_state *crtc_state;
> + u32 fmt;
> +
> + if (!fb || !state->crtc)
> + return 0;
> +
> + fmt = drm_format_to_dpu(fb);
> + if (!fmt)
> + return -EINVAL;
> +
> + crtc_state = drm_atomic_get_crtc_state(state->state, state->crtc);
> + if (IS_ERR(crtc_state))
> + return PTR_ERR(crtc_state);
> +
> + return drm_atomic_helper_check_plane_state(state, crtc_state,
> + DRM_PLANE_HELPER_NO_SCALING,
> + DRM_PLANE_HELPER_NO_SCALING,
> + true, true);
> +}
> +
> +static void sprd_plane_atomic_update(struct drm_plane *plane,
> + struct drm_plane_state *old_state)
> +{
> + struct drm_plane_state *state = plane->state;
> + struct sprd_plane *p = to_sprd_plane(plane);
> + struct sprd_dpu *dpu = to_sprd_crtc(state->crtc);
> +
> + /* start configure dpu layers */
> + sprd_dpu_layer(dpu, p, state);
> +}
> +
> +static void sprd_plane_atomic_disable(struct drm_plane *plane,
> + struct drm_plane_state *old_state)
> +{
> + struct sprd_plane *p = to_sprd_plane(plane);
> + struct sprd_dpu *dpu = to_sprd_crtc(old_state->crtc);
> +
> + layer_reg_wr(&dpu->ctx, REG_LAY_CTRL, 0x00, p->index);
> +}
> +
> +static void sprd_plane_create_properties(struct sprd_plane *p, int index)
> +{
> + unsigned int supported_modes = BIT(DRM_MODE_BLEND_PIXEL_NONE) |
> + BIT(DRM_MODE_BLEND_PREMULTI) |
> + BIT(DRM_MODE_BLEND_COVERAGE);
> +
> + /* create rotation property */
> + drm_plane_create_rotation_property(&p->plane,
> + DRM_MODE_ROTATE_0,
> + DRM_MODE_ROTATE_MASK |
> + DRM_MODE_REFLECT_MASK);
> +
> + /* create alpha property */
> + drm_plane_create_alpha_property(&p->plane);
> +
> + /* create blend mode property */
> + drm_plane_create_blend_mode_property(&p->plane, supported_modes);
> +
> + /* create zpos property */
> + drm_plane_create_zpos_immutable_property(&p->plane, index);
> +}
> +
> +static const struct drm_plane_helper_funcs sprd_plane_helper_funcs = {
> + .atomic_check = sprd_plane_atomic_check,
> + .atomic_update = sprd_plane_atomic_update,
> + .atomic_disable = sprd_plane_atomic_disable,
> +};
> +
> +static const struct drm_plane_funcs sprd_plane_funcs = {
> + .update_plane = drm_atomic_helper_update_plane,
> + .disable_plane = drm_atomic_helper_disable_plane,
> + .destroy = drm_plane_cleanup,
> + .reset = drm_atomic_helper_plane_reset,
> + .atomic_duplicate_state = drm_atomic_helper_plane_duplicate_state,
> + .atomic_destroy_state = drm_atomic_helper_plane_destroy_state,
> +};
> +
> +static struct drm_plane *sprd_plane_init(struct drm_device *drm,
> + struct sprd_dpu *dpu)
> +{
> + struct drm_plane *primary = NULL;
> + struct sprd_plane *p = NULL;
> + int ret, i;
> +
> + for (i = 0; i < 6; i++) {
> + p = devm_kzalloc(drm->dev, sizeof(*p), GFP_KERNEL);
> + if (!p)
> + return ERR_PTR(-ENOMEM);
> +
> + ret = drm_universal_plane_init(drm, &p->plane, 1,
> + &sprd_plane_funcs, primary_fmts,
> + ARRAY_SIZE(primary_fmts), NULL,
> + DRM_PLANE_TYPE_PRIMARY, NULL);
> + if (ret) {
> + drm_err(drm, "fail to init primary plane\n");
> + return ERR_PTR(ret);
> + }
> +
> + drm_plane_helper_add(&p->plane, &sprd_plane_helper_funcs);
> +
> + sprd_plane_create_properties(p, i);
> +
> + p->index = i;
> + if (i == 0)
> + primary = &p->plane;
> + }
> +
> + return primary;
> +}
> +
> +static enum drm_mode_status sprd_crtc_mode_valid(struct drm_crtc *crtc,
> + const struct drm_display_mode *mode)
> +{
> + struct sprd_dpu *dpu = to_sprd_crtc(crtc);
> +
> + drm_dbg(dpu->drm, "%s() mode: "DRM_MODE_FMT"\n", __func__, DRM_MODE_ARG(mode));
> +
> + if (mode->type & DRM_MODE_TYPE_PREFERRED) {
> + drm_display_mode_to_videomode(mode, &dpu->ctx.vm);
> +
> + if ((mode->hdisplay == mode->htotal) ||
> + (mode->vdisplay == mode->vtotal))
> + dpu->ctx.if_type = SPRD_DPU_IF_EDPI;
> + else
> + dpu->ctx.if_type = SPRD_DPU_IF_DPI;
> + }
> +
> + return MODE_OK;
> +}
> +
> +static void sprd_crtc_atomic_enable(struct drm_crtc *crtc,
> + struct drm_crtc_state *old_state)
> +{
> + struct sprd_dpu *dpu = to_sprd_crtc(crtc);
> +
> + sprd_dpu_init(dpu);
> +
> + sprd_dpi_init(dpu);
> +
> + enable_irq(dpu->ctx.irq);
> +
> + drm_crtc_vblank_on(&dpu->crtc);
> +}
> +
> +static void sprd_crtc_atomic_disable(struct drm_crtc *crtc,
> + struct drm_crtc_state *old_state)
> +{
> + struct sprd_dpu *dpu = to_sprd_crtc(crtc);
> + struct drm_device *drm = dpu->crtc.dev;
> +
> + drm_crtc_vblank_off(&dpu->crtc);
> +
> + disable_irq(dpu->ctx.irq);
> +
> + sprd_dpu_fini(dpu);
> +
> + spin_lock_irq(&drm->event_lock);
> + if (crtc->state->event) {
> + drm_crtc_send_vblank_event(crtc, crtc->state->event);
> + crtc->state->event = NULL;
> + }
> + spin_unlock_irq(&drm->event_lock);
> +}
> +
> +static int sprd_crtc_atomic_check(struct drm_crtc *crtc,
> + struct drm_crtc_state *state)
> +{
> + drm_dbg(crtc->dev, "%s()\n", __func__);
> +
> + return 0;
> +}
> +
> +static void sprd_crtc_atomic_flush(struct drm_crtc *crtc,
> + struct drm_crtc_state *old_state)
> +
> +{
> + struct sprd_dpu *dpu = to_sprd_crtc(crtc);
> + struct drm_device *drm = dpu->crtc.dev;
> +
> + sprd_dpu_flip(dpu);
> +
> + spin_lock_irq(&drm->event_lock);
> + if (crtc->state->event) {
> + drm_crtc_send_vblank_event(crtc, crtc->state->event);
> + crtc->state->event = NULL;
> + }
> + spin_unlock_irq(&drm->event_lock);
> +}
> +
> +static int sprd_crtc_enable_vblank(struct drm_crtc *crtc)
> +{
> + struct sprd_dpu *dpu = to_sprd_crtc(crtc);
> +
> + dpu_reg_set(&dpu->ctx, REG_DPU_INT_EN, BIT_DPU_INT_VSYNC);
> +
> + return 0;
> +}
> +
> +static void sprd_crtc_disable_vblank(struct drm_crtc *crtc)
> +{
> + struct sprd_dpu *dpu = to_sprd_crtc(crtc);
> +
> + dpu_reg_clr(&dpu->ctx, REG_DPU_INT_EN, BIT_DPU_INT_VSYNC);
> +}
> +
> +static const struct drm_crtc_helper_funcs sprd_crtc_helper_funcs = {
> + .mode_valid = sprd_crtc_mode_valid,
> + .atomic_check = sprd_crtc_atomic_check,
> + .atomic_flush = sprd_crtc_atomic_flush,
> + .atomic_enable = sprd_crtc_atomic_enable,
> + .atomic_disable = sprd_crtc_atomic_disable,
> +};
> +
> +static const struct drm_crtc_funcs sprd_crtc_funcs = {
> + .destroy = drm_crtc_cleanup,
> + .set_config = drm_atomic_helper_set_config,
> + .page_flip = drm_atomic_helper_page_flip,
> + .reset = drm_atomic_helper_crtc_reset,
> + .atomic_duplicate_state = drm_atomic_helper_crtc_duplicate_state,
> + .atomic_destroy_state = drm_atomic_helper_crtc_destroy_state,
> + .enable_vblank = sprd_crtc_enable_vblank,
> + .disable_vblank = sprd_crtc_disable_vblank,
> +};
> +
> +static int sprd_crtc_init(struct drm_device *drm, struct drm_crtc *crtc,
> + struct drm_plane *primary)
> +{
> + struct device_node *port;
> + int ret;
> +
> + /*
> + * set crtc port so that drm_of_find_possible_crtcs call works
> + */
> + port = of_parse_phandle(drm->dev->of_node, "ports", 0);
> + if (!port) {
> + drm_err(drm, "find 'ports' phandle of %s failed\n",
> + drm->dev->of_node->full_name);
> + return -EINVAL;
> + }
> + of_node_put(port);
> + crtc->port = port;
> +
> + ret = drm_crtc_init_with_planes(drm, crtc, primary, NULL,
> + &sprd_crtc_funcs, NULL);
> + if (ret) {
> + drm_err(drm, "failed to init crtc.\n");
> + return ret;
> + }
> +
> + drm_crtc_helper_add(crtc, &sprd_crtc_helper_funcs);
> +
> + return 0;
> +}
> +
> +static irqreturn_t sprd_dpu_isr(int irq, void *data)
> +{
> + struct sprd_dpu *dpu = data;
> + struct dpu_context *ctx = &dpu->ctx;
> + u32 reg_val, int_mask = 0;
> +
> + reg_val = readl(ctx->base + REG_DPU_INT_STS);
> +
> + /* disable err interrupt */
> + if (reg_val & BIT_DPU_INT_ERR) {
> + int_mask |= BIT_DPU_INT_ERR;
> + drm_warn(dpu->drm, "Warning: dpu underflow!\n");
> + }
> +
> + /* dpu update done isr */
> + if (reg_val & BIT_DPU_INT_UPDATE_DONE) {
> + ctx->evt_update = true;
> + wake_up_interruptible_all(&ctx->wait_queue);
> + }
> +
> + /* dpu stop done isr */
> + if (reg_val & BIT_DPU_INT_DONE) {
> + ctx->evt_stop = true;
> + wake_up_interruptible_all(&ctx->wait_queue);
> + }
> +
> + if (reg_val & BIT_DPU_INT_VSYNC)
> + drm_crtc_handle_vblank(&dpu->crtc);
> +
> + int_mask |= check_mmu_isr(dpu, reg_val);
> +
> + writel(reg_val, ctx->base + REG_DPU_INT_CLR);
> + dpu_reg_clr(ctx, REG_DPU_INT_EN, int_mask);
> +
> + return IRQ_HANDLED;
> +}
> +
> +static int sprd_dpu_bind(struct device *dev, struct device *master, void *data)
> +{
> + struct drm_device *drm = data;
> + struct sprd_dpu *dpu = dev_get_drvdata(dev);
> + struct drm_plane *plane;
> + int ret;
> +
> + plane = sprd_plane_init(drm, dpu);
> + if (IS_ERR_OR_NULL(plane)) {
> + ret = PTR_ERR(plane);
> + return ret;
> + }
> +
> + ret = sprd_crtc_init(drm, &dpu->crtc, plane);
> + if (ret)
> + return ret;
> +
> + dpu->drm = drm;
> +
> + return 0;
> +}
> +
> +static void sprd_dpu_unbind(struct device *dev, struct device *master,
> + void *data)
> +{
> + struct sprd_dpu *dpu = dev_get_drvdata(dev);
> +
> + drm_crtc_cleanup(&dpu->crtc);
> +}
> +
> +static const struct component_ops dpu_component_ops = {
> + .bind = sprd_dpu_bind,
> + .unbind = sprd_dpu_unbind,
> +};
> +
> +static int sprd_dpu_context_init(struct sprd_dpu *dpu,
> + struct device *dev)
> +{
> + struct platform_device *pdev = to_platform_device(dev);
> + struct dpu_context *ctx = &dpu->ctx;
> + struct resource *res;
> + int ret;
> +
> + res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
> + ctx->base = devm_ioremap(dev, res->start, resource_size(res));
> + if (!ctx->base) {
> + dev_err(dev, "failed to map dpu registers\n");
> + return -EFAULT;
> + }
> +
> + ctx->irq = platform_get_irq(pdev, 0);
> + if (ctx->irq < 0) {
> + dev_err(dev, "failed to get dpu irq\n");
> + return ctx->irq;
> + }
> +
> + irq_set_status_flags(ctx->irq, IRQ_NOAUTOEN);
> + ret = devm_request_irq(dev, ctx->irq, sprd_dpu_isr,
> + 0, "DPU", dpu);
> + if (ret) {
> + dev_err(dev, "failed to register dpu irq handler\n");
> + return ret;
> + }
> +
> + init_waitqueue_head(&ctx->wait_queue);
> +
> + return 0;
> +}
> +
> +static const struct of_device_id dpu_match_table[] = {
> + { .compatible = "sprd,sharkl3-dpu" },
> + { /* sentinel */ },
> +};
> +
> +static int sprd_dpu_probe(struct platform_device *pdev)
> +{
> + struct sprd_dpu *dpu;
> + int ret;
> +
> + dpu = kzalloc(sizeof(*dpu), GFP_KERNEL);
> + if (!dpu)
> + return -ENOMEM;
> +
> + ret = sprd_dpu_context_init(dpu, &pdev->dev);
> + if (ret) {
> + kfree(dpu);
> + return ret;
> + }
> +
> + platform_set_drvdata(pdev, dpu);
> +
> + return component_add(&pdev->dev, &dpu_component_ops);
> +}
> +
> +static int sprd_dpu_remove(struct platform_device *pdev)
> +{
> + struct sprd_dpu *dpu = platform_get_drvdata(pdev);
> +
> + component_del(&pdev->dev, &dpu_component_ops);
> +
> + kfree(dpu);
> + return 0;
> +}
> +
> +struct platform_driver sprd_dpu_driver = {
> + .probe = sprd_dpu_probe,
> + .remove = sprd_dpu_remove,
> + .driver = {
> + .name = "sprd-dpu-drv",
> + .of_match_table = dpu_match_table,
> + },
> +};
> +
> +MODULE_AUTHOR("Leon He <leon.he@xxxxxxxxxx>");
> +MODULE_AUTHOR("Kevin Tang <kevin.tang@xxxxxxxxxx>");
> +MODULE_DESCRIPTION("Unisoc Display Controller Driver");
> +MODULE_LICENSE("GPL v2");
> diff --git a/drivers/gpu/drm/sprd/sprd_dpu.h b/drivers/gpu/drm/sprd/sprd_dpu.h
> new file mode 100644
> index 0000000..a937ba1
> --- /dev/null
> +++ b/drivers/gpu/drm/sprd/sprd_dpu.h
> @@ -0,0 +1,120 @@
> +/* SPDX-License-Identifier: GPL-2.0 */
> +/*
> + * Copyright (C) 2020 Unisoc Inc.
> + */
> +
> +#ifndef __SPRD_DPU_H__
> +#define __SPRD_DPU_H__
> +
> +#include <linux/bug.h>
> +#include <linux/delay.h>
> +#include <linux/device.h>
> +#include <linux/kernel.h>
> +#include <linux/platform_device.h>
> +#include <linux/string.h>
> +#include <video/videomode.h>
> +
> +#include <drm/drm_crtc.h>
> +#include <drm/drm_fourcc.h>
> +#include <drm/drm_print.h>
> +#include <drm/drm_vblank.h>
> +#include <uapi/drm/drm_mode.h>
> +
> +/* DPU Layer registers offset */
> +#define DPU_LAY_REG_OFFSET 0x30
> +
> +enum {
> + SPRD_DPU_IF_DBI = 0,
> + SPRD_DPU_IF_DPI,
> + SPRD_DPU_IF_EDPI,
> + SPRD_DPU_IF_LIMIT
> +};
Above seems unused, so not sure what it is?
> +
> +enum {
> + DPU_LAYER_ROTATION_0,
> + DPU_LAYER_ROTATION_90,
> + DPU_LAYER_ROTATION_180,
> + DPU_LAYER_ROTATION_270,
> + DPU_LAYER_ROTATION_0_M,
> + DPU_LAYER_ROTATION_90_M,
> + DPU_LAYER_ROTATION_180_M,
> + DPU_LAYER_ROTATION_270_M,
> +};
Since this seems to be hw register definitions please use #define
constants and maybe move them to all the other register definitions too?
-Daniel
> +
> +/**
> + * Sprd DPU context structure
> + *
> + * @base: DPU controller base address
> + * @irq: IRQ number to install the handler for
> + * @if_type: The type of DPI interface, default is DPI mode.
> + * @vm: videomode structure to use for DPU and DPI initialization
> + * @stopped: indicates whether DPU are stopped
> + * @wait_queue: wait queue, used to wait for DPU shadow register update done and
> + * DPU stop register done interrupt signal.
> + * @evt_update: wait queue condition for DPU shadow register
> + * @evt_stop: wait queue condition for DPU stop register
> + */
> +struct dpu_context {
> + void __iomem *base;
> + int irq;
> + u8 if_type;
> + struct videomode vm;
> + bool stopped;
> + wait_queue_head_t wait_queue;
> + bool evt_update;
> + bool evt_stop;
> +};
> +
> +/**
> + * Sprd DPU device structure
> + *
> + * @crtc: DRM crtc
> + * @ctx: A pointer to the DPU's implementation specific context
> + */
> +struct sprd_dpu {
> + struct drm_crtc crtc;
> + struct drm_device *drm;
> + struct dpu_context ctx;
> +};
> +
> +static inline struct sprd_dpu *to_sprd_crtc(struct drm_crtc *crtc)
> +{
> + return container_of(crtc, struct sprd_dpu, crtc);
> +}
> +
> +static inline void
> +dpu_reg_set(struct dpu_context *ctx, u32 offset, u32 set_bits)
> +{
> + u32 bits = readl_relaxed(ctx->base + offset);
> +
> + writel(bits | set_bits, ctx->base + offset);
> +}
> +
> +static inline void
> +dpu_reg_clr(struct dpu_context *ctx, u32 offset, u32 clr_bits)
> +{
> + u32 bits = readl_relaxed(ctx->base + offset);
> +
> + writel(bits & ~clr_bits, ctx->base + offset);
> +}
> +
> +static inline u32
> +layer_reg_rd(struct dpu_context *ctx, u32 offset, int index)
> +{
> + u32 layer_offset = offset + index * DPU_LAY_REG_OFFSET;
> +
> + return readl(ctx->base + layer_offset);
> +}
> +
> +static inline void
> +layer_reg_wr(struct dpu_context *ctx, u32 offset, u32 cfg_bits, int index)
> +{
> + u32 layer_offset = offset + index * DPU_LAY_REG_OFFSET;
> +
> + writel(cfg_bits, ctx->base + layer_offset);
> +}
> +
> +void sprd_dpu_run(struct sprd_dpu *dpu);
> +void sprd_dpu_stop(struct sprd_dpu *dpu);
> +
> +#endif
> diff --git a/drivers/gpu/drm/sprd/sprd_drm.c b/drivers/gpu/drm/sprd/sprd_drm.c
> index ec101de..ca93be2 100644
> --- a/drivers/gpu/drm/sprd/sprd_drm.c
> +++ b/drivers/gpu/drm/sprd/sprd_drm.c
> @@ -196,6 +196,7 @@ static struct platform_driver sprd_drm_driver = {
>
> static struct platform_driver *sprd_drm_drivers[] = {
> &sprd_drm_driver,
> + &sprd_dpu_driver,
> };
>
> static int __init sprd_drm_init(void)
> diff --git a/drivers/gpu/drm/sprd/sprd_drm.h b/drivers/gpu/drm/sprd/sprd_drm.h
> index 9781fd5..85d4a8b 100644
> --- a/drivers/gpu/drm/sprd/sprd_drm.h
> +++ b/drivers/gpu/drm/sprd/sprd_drm.h
> @@ -13,4 +13,6 @@ struct sprd_drm {
> struct drm_device drm;
> };
>
> +extern struct platform_driver sprd_dpu_driver;
> +
> #endif /* _SPRD_DRM_H_ */
> --
> 2.7.4
>
--
Daniel Vetter
Software Engineer, Intel Corporation
http://blog.ffwll.ch