From 1f23a56a46b81de50eb8b898f06296ca06720a99 Mon Sep 17 00:00:00 2001 From: Jamie Fox Date: Mon, 1 Oct 2018 14:39:07 +0100 Subject: drm/malidp: Enable MMU prefetch on Mali-DP650 Mali-DP650 supports warming up the SMMU translations, by sending requsts to the SMMU before a buffer is read. There are two modes supported: - PARTIAL: could be enabled when the buffer is composed of 4K or 64K pages, the display hardware will send a configurable number of requests before the actual reading. - FULL: could be enabled when the buffer is composed of 1M or 2M pages, the display hardware will send requests before reading for all pages composing the buffer. This patch adds a mechanism for detecting the page size and set the MMU prefetch mode if possible. Changes since v1: - For imported buffers use the already populated drm_gem_cma_object.sgt instead of calling driver.gem_prime_get_sg_table, which works just for buffers allocated through the gem_cma API. Signed-off-by: Jamie Fox Signed-off-by: Alexandru Gheorghe Acked-by: Liviu Dudau [rebased and re-ordered functions] Signed-off-by: Liviu Dudau --- drivers/gpu/drm/arm/malidp_planes.c | 238 ++++++++++++++++++++++++++++++++++++ 1 file changed, 238 insertions(+) (limited to 'drivers/gpu/drm/arm/malidp_planes.c') diff --git a/drivers/gpu/drm/arm/malidp_planes.c b/drivers/gpu/drm/arm/malidp_planes.c index 39416bcd880e..76aafc296e1b 100644 --- a/drivers/gpu/drm/arm/malidp_planes.c +++ b/drivers/gpu/drm/arm/malidp_planes.c @@ -10,11 +10,14 @@ * ARM Mali DP plane manipulation routines. */ +#include + #include #include #include #include #include +#include #include #include @@ -57,6 +60,13 @@ */ #define MALIDP_ALPHA_LUT 0xffaa5500 +/* page sizes the MMU prefetcher can support */ +#define MALIDP_MMU_PREFETCH_PARTIAL_PGSIZES (SZ_4K | SZ_64K) +#define MALIDP_MMU_PREFETCH_FULL_PGSIZES (SZ_1M | SZ_2M) + +/* readahead for partial-frame prefetch */ +#define MALIDP_MMU_PREFETCH_READAHEAD 8 + static void malidp_de_plane_destroy(struct drm_plane *plane) { struct malidp_plane *mp = to_malidp_plane(plane); @@ -101,6 +111,9 @@ drm_plane_state *malidp_duplicate_plane_state(struct drm_plane *plane) state->format = m_state->format; state->n_planes = m_state->n_planes; + state->mmu_prefetch_mode = m_state->mmu_prefetch_mode; + state->mmu_prefetch_pgsize = m_state->mmu_prefetch_pgsize; + return &state->base; } @@ -113,6 +126,12 @@ static void malidp_destroy_plane_state(struct drm_plane *plane, kfree(m_state); } +static const char * const prefetch_mode_names[] = { + [MALIDP_PREFETCH_MODE_NONE] = "MMU_PREFETCH_NONE", + [MALIDP_PREFETCH_MODE_PARTIAL] = "MMU_PREFETCH_PARTIAL", + [MALIDP_PREFETCH_MODE_FULL] = "MMU_PREFETCH_FULL", +}; + static void malidp_plane_atomic_print_state(struct drm_printer *p, const struct drm_plane_state *state) { @@ -121,6 +140,9 @@ static void malidp_plane_atomic_print_state(struct drm_printer *p, drm_printf(p, "\trotmem_size=%u\n", ms->rotmem_size); drm_printf(p, "\tformat_id=%u\n", ms->format); drm_printf(p, "\tn_planes=%u\n", ms->n_planes); + drm_printf(p, "\tmmu_prefetch_mode=%s\n", + prefetch_mode_names[ms->mmu_prefetch_mode]); + drm_printf(p, "\tmmu_prefetch_pgsize=%d\n", ms->mmu_prefetch_pgsize); } static const struct drm_plane_funcs malidp_de_plane_funcs = { @@ -174,6 +196,199 @@ static int malidp_se_check_scaling(struct malidp_plane *mp, return 0; } +static u32 malidp_get_pgsize_bitmap(struct malidp_plane *mp) +{ + u32 pgsize_bitmap = 0; + + if (iommu_present(&platform_bus_type)) { + struct iommu_domain *mmu_dom = + iommu_get_domain_for_dev(mp->base.dev->dev); + + if (mmu_dom) + pgsize_bitmap = mmu_dom->pgsize_bitmap; + } + + return pgsize_bitmap; +} + +/* + * Check if the framebuffer is entirely made up of pages at least pgsize in + * size. Only a heuristic: assumes that each scatterlist entry has been aligned + * to the largest page size smaller than its length and that the MMU maps to + * the largest page size possible. + */ +static bool malidp_check_pages_threshold(struct malidp_plane_state *ms, + u32 pgsize) +{ + int i; + + for (i = 0; i < ms->n_planes; i++) { + struct drm_gem_object *obj; + struct drm_gem_cma_object *cma_obj; + struct sg_table *sgt; + struct scatterlist *sgl; + + obj = drm_gem_fb_get_obj(ms->base.fb, i); + cma_obj = to_drm_gem_cma_obj(obj); + + if (cma_obj->sgt) + sgt = cma_obj->sgt; + else + sgt = obj->dev->driver->gem_prime_get_sg_table(obj); + + if (!sgt) + return false; + + sgl = sgt->sgl; + + while (sgl) { + if (sgl->length < pgsize) { + if (!cma_obj->sgt) + kfree(sgt); + return false; + } + + sgl = sg_next(sgl); + } + if (!cma_obj->sgt) + kfree(sgt); + } + + return true; +} + +/* + * Check if it is possible to enable partial-frame MMU prefetch given the + * current format, AFBC state and rotation. + */ +static bool malidp_partial_prefetch_supported(u32 format, u64 modifier, + unsigned int rotation) +{ + bool afbc, sparse; + + /* rotation and horizontal flip not supported for partial prefetch */ + if (rotation & (DRM_MODE_ROTATE_90 | DRM_MODE_ROTATE_180 | + DRM_MODE_ROTATE_270 | DRM_MODE_REFLECT_X)) + return false; + + afbc = modifier & DRM_FORMAT_MOD_ARM_AFBC(0); + sparse = modifier & AFBC_FORMAT_MOD_SPARSE; + + switch (format) { + case DRM_FORMAT_ARGB2101010: + case DRM_FORMAT_RGBA1010102: + case DRM_FORMAT_BGRA1010102: + case DRM_FORMAT_ARGB8888: + case DRM_FORMAT_RGBA8888: + case DRM_FORMAT_BGRA8888: + case DRM_FORMAT_XRGB8888: + case DRM_FORMAT_XBGR8888: + case DRM_FORMAT_RGBX8888: + case DRM_FORMAT_BGRX8888: + case DRM_FORMAT_RGB888: + case DRM_FORMAT_RGBA5551: + case DRM_FORMAT_RGB565: + /* always supported */ + return true; + + case DRM_FORMAT_ABGR2101010: + case DRM_FORMAT_ABGR8888: + case DRM_FORMAT_ABGR1555: + case DRM_FORMAT_BGR565: + /* supported, but if AFBC then must be sparse mode */ + return (!afbc) || (afbc && sparse); + + case DRM_FORMAT_BGR888: + /* supported, but not for AFBC */ + return !afbc; + + case DRM_FORMAT_YUYV: + case DRM_FORMAT_UYVY: + case DRM_FORMAT_NV12: + case DRM_FORMAT_YUV420: + /* not supported */ + return false; + + default: + return false; + } +} + +/* + * Select the preferred MMU prefetch mode. Full-frame prefetch is preferred as + * long as the framebuffer is all large pages. Otherwise partial-frame prefetch + * is selected as long as it is supported for the current format. The selected + * page size for prefetch is returned in pgsize_bitmap. + */ +static enum mmu_prefetch_mode malidp_mmu_prefetch_select_mode + (struct malidp_plane_state *ms, u32 *pgsize_bitmap) +{ + u32 pgsizes; + + /* get the full-frame prefetch page size(s) supported by the MMU */ + pgsizes = *pgsize_bitmap & MALIDP_MMU_PREFETCH_FULL_PGSIZES; + + while (pgsizes) { + u32 largest_pgsize = 1 << __fls(pgsizes); + + if (malidp_check_pages_threshold(ms, largest_pgsize)) { + *pgsize_bitmap = largest_pgsize; + return MALIDP_PREFETCH_MODE_FULL; + } + + pgsizes -= largest_pgsize; + } + + /* get the partial-frame prefetch page size(s) supported by the MMU */ + pgsizes = *pgsize_bitmap & MALIDP_MMU_PREFETCH_PARTIAL_PGSIZES; + + if (malidp_partial_prefetch_supported(ms->base.fb->format->format, + ms->base.fb->modifier, + ms->base.rotation)) { + /* partial prefetch using the smallest page size */ + *pgsize_bitmap = 1 << __ffs(pgsizes); + return MALIDP_PREFETCH_MODE_PARTIAL; + } + *pgsize_bitmap = 0; + return MALIDP_PREFETCH_MODE_NONE; +} + +static u32 malidp_calc_mmu_control_value(enum mmu_prefetch_mode mode, + u8 readahead, u8 n_planes, u32 pgsize) +{ + u32 mmu_ctrl = 0; + + if (mode != MALIDP_PREFETCH_MODE_NONE) { + mmu_ctrl |= MALIDP_MMU_CTRL_EN; + + if (mode == MALIDP_PREFETCH_MODE_PARTIAL) { + mmu_ctrl |= MALIDP_MMU_CTRL_MODE; + mmu_ctrl |= MALIDP_MMU_CTRL_PP_NUM_REQ(readahead); + } + + if (pgsize == SZ_64K || pgsize == SZ_2M) { + int i; + + for (i = 0; i < n_planes; i++) + mmu_ctrl |= MALIDP_MMU_CTRL_PX_PS(i); + } + } + + return mmu_ctrl; +} + +static void malidp_de_prefetch_settings(struct malidp_plane *mp, + struct malidp_plane_state *ms) +{ + if (!mp->layer->mmu_ctrl_offset) + return; + + /* get the page sizes supported by the MMU */ + ms->mmu_prefetch_pgsize = malidp_get_pgsize_bitmap(mp); + ms->mmu_prefetch_mode = + malidp_mmu_prefetch_select_mode(ms, &ms->mmu_prefetch_pgsize); +} + static int malidp_de_plane_check(struct drm_plane *plane, struct drm_plane_state *state) { @@ -250,6 +465,8 @@ static int malidp_de_plane_check(struct drm_plane *plane, fb->format->has_alpha) return -EINVAL; + malidp_de_prefetch_settings(mp, ms); + return 0; } @@ -326,6 +543,24 @@ static void malidp_de_set_color_encoding(struct malidp_plane *plane, } } +static void malidp_de_set_mmu_control(struct malidp_plane *mp, + struct malidp_plane_state *ms) +{ + u32 mmu_ctrl; + + /* check hardware supports MMU prefetch */ + if (!mp->layer->mmu_ctrl_offset) + return; + + mmu_ctrl = malidp_calc_mmu_control_value(ms->mmu_prefetch_mode, + MALIDP_MMU_PREFETCH_READAHEAD, + ms->n_planes, + ms->mmu_prefetch_pgsize); + + malidp_hw_write(mp->hwdev, mmu_ctrl, + mp->layer->base + mp->layer->mmu_ctrl_offset); +} + static void malidp_de_plane_update(struct drm_plane *plane, struct drm_plane_state *old_state) { @@ -358,6 +593,9 @@ static void malidp_de_plane_update(struct drm_plane *plane, malidp_hw_write(mp->hwdev, lower_32_bits(fb_addr), ptr); malidp_hw_write(mp->hwdev, upper_32_bits(fb_addr), ptr + 4); } + + malidp_de_set_mmu_control(mp, ms); + malidp_de_set_plane_pitches(mp, ms->n_planes, state->fb->pitches); -- cgit