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Lin" , Fei Shao , Sean Paul , Jason Chen , , , , , "Hsiao Chien Sung" Subject: [PATCH v7 16/18] drm/mediatek: Support CRC in display driver Date: Thu, 2 May 2024 18:38:46 +0800 Message-ID: <20240502103848.5845-17-shawn.sung@mediatek.com> X-Mailer: git-send-email 2.18.0 In-Reply-To: <20240502103848.5845-1-shawn.sung@mediatek.com> References: <20240502103848.5845-1-shawn.sung@mediatek.com> MIME-Version: 1.0 X-TM-AS-Product-Ver: SMEX-14.0.0.3152-9.1.1006-23728.005 X-TM-AS-Result: No-10--11.935200-8.000000 X-TMASE-MatchedRID: 8h/WK3ruO5pLCiMVfxYIMFVN8laWo90MnhD9A3Sa7pYs/uUAk6xP7MRr vjvFKTaxGJHAl8RgcXDdzcJEB3Zs4ah+3Rlbev+J4bl1FkKDELdaav/yaeMwblwpnAAvAwazTDu zDhf7V2fGQ0Mzn7Pg3VMxeZNUL/sPC8AHgPiWV4hCnGIuUMP0VZnaxzJFBx6vv8D7QPW2jo8+O1 R2R6ljypjGRDY1Ty3MflkRI5fbnRKOqU9B1spa9hWCVBr+Ay98aN2KuTwsCwIUHVz/b87KIw2yB nqOBZsS1aYQghjejxGDvpNQRtj+jy1+34qxqAZfoS0guoV6SZcuhg66Itb65c2mvbig5LjGIe/o 8I0yOxLhZtas1avqAfOyU5djegMk2DBKoUnK0AUXrP0cYcrA23nL427v8Q46AVscD1Oo0tBsgo+ 5BhUuW398JFL2cDef9DomuZeNnSaQFHd0cGjNx0f49ONH0RaSFJFr2qlKix8Dv2aLHYU+KHlsGJ Xt79WMvT6pHvydqvcRu3AibWiOpTS6KnCjb0iuB7TqRAYVohZn+sA9+u1YLUk7tZaD19NMo8WMk QWv6iXBcIE78YqRWvcUt5lc1lLgoGRyAacnhaamaai8W/VtAIiD2nxfUJ+U8EZig2ZEfhqi05Nd tDuyAH7cGd19dSFd X-TM-AS-User-Approved-Sender: No X-TM-AS-User-Blocked-Sender: No X-TMASE-Result: 10--11.935200-8.000000 X-TMASE-Version: SMEX-14.0.0.3152-9.1.1006-23728.005 X-TM-SNTS-SMTP: 1C3F022A24B73FB24DBEBC5A8064D3B459B35A8F786248017D3A8E434597F59A2000:8 X-MTK: N X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20240502_033906_308112_187B7AB8 X-CRM114-Status: GOOD ( 30.50 ) X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org From: Hsiao Chien Sung Register CRC related function pointers to support CRC retrieval. Signed-off-by: Hsiao Chien Sung --- drivers/gpu/drm/mediatek/mtk_crtc.c | 260 ++++++++++++++++++++++++ drivers/gpu/drm/mediatek/mtk_crtc.h | 38 ++++ drivers/gpu/drm/mediatek/mtk_ddp_comp.h | 3 + 3 files changed, 301 insertions(+) diff --git a/drivers/gpu/drm/mediatek/mtk_crtc.c b/drivers/gpu/drm/mediatek/mtk_crtc.c index 6f34f573e127e..29d00d11224b0 100644 --- a/drivers/gpu/drm/mediatek/mtk_crtc.c +++ b/drivers/gpu/drm/mediatek/mtk_crtc.c @@ -18,6 +18,7 @@ #include #include #include +#include #include "mtk_crtc.h" #include "mtk_ddp_comp.h" @@ -69,6 +70,9 @@ struct mtk_crtc { /* lock for display hardware access */ struct mutex hw_lock; bool config_updating; + + struct mtk_ddp_comp *crc_provider; + struct drm_vblank_work crc_work; }; struct mtk_crtc_state { @@ -703,6 +707,71 @@ static void mtk_crtc_update_output(struct drm_crtc *crtc, } } +static void mtk_crtc_crc_work(struct kthread_work *base) +{ + struct drm_vblank_work *work = to_drm_vblank_work(base); + struct mtk_crtc *mtk_crtc = + container_of(work, typeof(*mtk_crtc), crc_work); + + if (mtk_crtc->base.crc.opened) { + struct mtk_ddp_comp *comp = mtk_crtc->crc_provider; + u64 vblank = drm_crtc_vblank_count(&mtk_crtc->base); + + comp->funcs->crc_read(comp->dev); + + /* could take more than 50ms to finish */ + drm_crtc_add_crc_entry(&mtk_crtc->base, true, vblank, + comp->funcs->crc_entry(comp->dev)); + + drm_vblank_work_schedule(&mtk_crtc->crc_work, vblank + 1, true); + } +} + +static int mtk_crtc_set_crc_source(struct drm_crtc *crtc, const char *src) +{ + struct mtk_crtc *mtk_crtc = to_mtk_crtc(crtc); + + if (!src) + return -EINVAL; + + if (strcmp(src, "auto") != 0) { + DRM_ERROR("%s(crtc-%d): unknown source '%s'\n", + __func__, drm_crtc_index(crtc), src); + return -EINVAL; + } + + /* + * skip the first crc because the first frame (vblank + 1) is configured + * by mtk_crtc_ddp_hw_init() when atomic enable + */ + drm_vblank_work_schedule(&mtk_crtc->crc_work, + drm_crtc_vblank_count(crtc) + 2, false); + return 0; +} + +static int mtk_crtc_verify_crc_source(struct drm_crtc *crtc, const char *src, + size_t *cnt) +{ + struct mtk_crtc *mtk_crtc = to_mtk_crtc(crtc); + struct mtk_ddp_comp *comp = mtk_crtc->crc_provider; + + if (!comp) { + DRM_ERROR("%s(crtc-%d): no crc provider\n", + __func__, drm_crtc_index(crtc)); + return -ENOENT; + } + + if (src && strcmp(src, "auto") != 0) { + DRM_ERROR("%s(crtc-%d): unknown source '%s'\n", + __func__, drm_crtc_index(crtc), src); + return -EINVAL; + } + + *cnt = comp->funcs->crc_cnt(comp->dev); + + return 0; +} + int mtk_crtc_plane_check(struct drm_crtc *crtc, struct drm_plane *plane, struct mtk_plane_state *state) { @@ -751,6 +820,8 @@ static void mtk_crtc_atomic_enable(struct drm_crtc *crtc, drm_crtc_vblank_on(crtc); mtk_crtc->enabled = true; + + drm_vblank_work_init(&mtk_crtc->crc_work, crtc, mtk_crtc_crc_work); } static void mtk_crtc_atomic_disable(struct drm_crtc *crtc, @@ -840,6 +911,8 @@ static const struct drm_crtc_funcs mtk_crtc_funcs = { .atomic_destroy_state = mtk_crtc_destroy_state, .enable_vblank = mtk_crtc_enable_vblank, .disable_vblank = mtk_crtc_disable_vblank, + .set_crc_source = mtk_crtc_set_crc_source, + .verify_crc_source = mtk_crtc_verify_crc_source, }; static const struct drm_crtc_helper_funcs mtk_crtc_helper_funcs = { @@ -1033,6 +1106,11 @@ int mtk_crtc_create(struct drm_device *drm_dev, const unsigned int *path, if (comp->funcs->ctm_set) has_ctm = true; + + if (comp->funcs->crc_cnt && + comp->funcs->crc_entry && + comp->funcs->crc_read) + mtk_crtc->crc_provider = comp; } mtk_ddp_comp_register_vblank_cb(comp, mtk_crtc_ddp_irq, @@ -1136,3 +1214,185 @@ int mtk_crtc_create(struct drm_device *drm_dev, const unsigned int *path, return 0; } + +void mtk_crtc_init_crc(struct mtk_crtc_crc *crc, const u32 *crc_offset_table, + size_t crc_count, u32 reset_offset, u32 reset_mask) +{ + crc->ofs = crc_offset_table; + crc->cnt = crc_count; + crc->rst_ofs = reset_offset; + crc->rst_msk = reset_mask; + crc->va = kcalloc(crc->cnt, sizeof(*crc->va), GFP_KERNEL); + if (!crc->va) { + DRM_ERROR("failed to allocate memory for crc\n"); + crc->cnt = 0; + } +} + +void mtk_crtc_read_crc(struct mtk_crtc_crc *crc, void __iomem *reg) +{ + if (!crc->cnt || !crc->ofs || !crc->va) + return; + +#if IS_REACHABLE(CONFIG_MTK_CMDQ) + /* sync to see the most up-to-date copy of the DMA buffer */ + dma_sync_single_for_cpu(crc->cmdq_client.chan->mbox->dev, + crc->pa, crc->cnt * sizeof(*crc->va), + DMA_FROM_DEVICE); +#endif +} + +void mtk_crtc_destroy_crc(struct mtk_crtc_crc *crc) +{ + if (!crc->cnt) + return; + +#if IS_REACHABLE(CONFIG_MTK_CMDQ) + if (crc->pa) { + dma_unmap_single(crc->cmdq_client.chan->mbox->dev, + crc->pa, crc->cnt * sizeof(*crc->va), + DMA_TO_DEVICE); + crc->pa = 0; + } + if (crc->cmdq_client.chan) { + mtk_drm_cmdq_pkt_destroy(&crc->cmdq_handle); + mbox_free_channel(crc->cmdq_client.chan); + crc->cmdq_client.chan = NULL; + } +#endif + kfree(crc->va); + crc->va = NULL; + crc->cnt = 0; +} + +#if IS_REACHABLE(CONFIG_MTK_CMDQ) +/** + * mtk_crtc_create_crc_cmdq - Create a CMDQ thread for syncing the CRCs + * @dev: Kernel device node of the CRC provider + * @crc: Pointer of the CRC to init + * + * This function will create a looping thread on GCE (Global Command Engine) to + * keep the CRC up to date by monitoring the assigned event (usually the frame + * done event) of the CRC provider, and read the CRCs from the registers to a + * shared memory for the workqueue to read. To start/stop the looping thread, + * please call `mtk_crtc_start_crc_cmdq()` and `mtk_crtc_stop_crc_cmdq()` + * defined blow. + * + * The reason why we don't update the CRCs with CPU is that the front porch of + * 4K60 timing in CEA-861 is less than 60us, and register read/write speed is + * relatively unreliable comparing to GCE due to the bus design. + * + * We must create a new thread instead of using the original one for plane + * update is because: + * 1. We cannot add another wait-for-event command at the end of cmdq packet, or + * the cmdq callback will delay for too long + * 2. Will get the CRC of the previous frame if using the existed wait-for-event + * command which is at the beginning of the packet + */ +void mtk_crtc_create_crc_cmdq(struct device *dev, struct mtk_crtc_crc *crc) +{ + int i; + + if (!crc->cnt) { + dev_warn(dev, "%s: not support\n", __func__); + goto cleanup; + } + + if (!crc->ofs) { + dev_warn(dev, "%s: not defined\n", __func__); + goto cleanup; + } + + crc->cmdq_client.client.dev = dev; + crc->cmdq_client.client.tx_block = false; + crc->cmdq_client.client.knows_txdone = true; + crc->cmdq_client.client.rx_callback = NULL; + crc->cmdq_client.chan = mbox_request_channel(&crc->cmdq_client.client, 0); + if (IS_ERR(crc->cmdq_client.chan)) { + dev_warn(dev, "%s: failed to create mailbox client\n", __func__); + crc->cmdq_client.chan = NULL; + goto cleanup; + } + + if (mtk_drm_cmdq_pkt_create(&crc->cmdq_client, &crc->cmdq_handle, PAGE_SIZE)) { + dev_warn(dev, "%s: failed to create cmdq packet\n", __func__); + goto cleanup; + } + + if (!crc->va) { + dev_warn(dev, "%s: no memory\n", __func__); + goto cleanup; + } + + /* map the entry to get a dma address for cmdq to store the crc */ + crc->pa = dma_map_single(crc->cmdq_client.chan->mbox->dev, + crc->va, crc->cnt * sizeof(*crc->va), + DMA_FROM_DEVICE); + + if (dma_mapping_error(crc->cmdq_client.chan->mbox->dev, crc->pa)) { + dev_err(dev, "%s: failed to map dma\n", __func__); + goto cleanup; + } + + if (crc->cmdq_event) + cmdq_pkt_wfe(&crc->cmdq_handle, crc->cmdq_event, true); + + for (i = 0; i < crc->cnt; i++) { + /* put crc to spr1 register */ + cmdq_pkt_read_s(&crc->cmdq_handle, crc->cmdq_reg->subsys, + crc->cmdq_reg->offset + crc->ofs[i], + CMDQ_THR_SPR_IDX1); + + /* copy spr1 register to physical address of the crc */ + cmdq_pkt_assign(&crc->cmdq_handle, CMDQ_THR_SPR_IDX0, + CMDQ_ADDR_HIGH(crc->pa + i * sizeof(*crc->va))); + cmdq_pkt_write_s(&crc->cmdq_handle, CMDQ_THR_SPR_IDX0, + CMDQ_ADDR_LOW(crc->pa + i * sizeof(*crc->va)), + CMDQ_THR_SPR_IDX1); + } + /* reset crc */ + mtk_ddp_write_mask(&crc->cmdq_handle, ~0, crc->cmdq_reg, 0, + crc->rst_ofs, crc->rst_msk); + + /* clear reset bit */ + mtk_ddp_write_mask(&crc->cmdq_handle, 0, crc->cmdq_reg, 0, + crc->rst_ofs, crc->rst_msk); + + /* jump to head of the cmdq packet */ + cmdq_pkt_jump(&crc->cmdq_handle, crc->cmdq_handle.pa_base); + + return; +cleanup: + mtk_crtc_destroy_crc(crc); +} + +/** + * mtk_crtc_start_crc_cmdq - Start the GCE looping thread for CRC update + * @crc: Pointer of the CRC information + */ +void mtk_crtc_start_crc_cmdq(struct mtk_crtc_crc *crc) +{ + if (!crc->cmdq_client.chan) + return; + + dma_sync_single_for_device(crc->cmdq_client.chan->mbox->dev, + crc->cmdq_handle.pa_base, + crc->cmdq_handle.cmd_buf_size, + DMA_TO_DEVICE); + mbox_send_message(crc->cmdq_client.chan, &crc->cmdq_handle); + mbox_client_txdone(crc->cmdq_client.chan, 0); +} + +/** + * mtk_crtc_stop_crc_cmdq - Stop the GCE looping thread for CRC update + * @crc: Pointer of the CRC information + */ +void mtk_crtc_stop_crc_cmdq(struct mtk_crtc_crc *crc) +{ + if (!crc->cmdq_client.chan) + return; + + /* remove all the commands from the cmdq packet */ + mbox_flush(crc->cmdq_client.chan, 2000); +} +#endif diff --git a/drivers/gpu/drm/mediatek/mtk_crtc.h b/drivers/gpu/drm/mediatek/mtk_crtc.h index 388e900b6f4de..a79c4611754e4 100644 --- a/drivers/gpu/drm/mediatek/mtk_crtc.h +++ b/drivers/gpu/drm/mediatek/mtk_crtc.h @@ -14,6 +14,34 @@ #define MTK_MAX_BPC 10 #define MTK_MIN_BPC 3 +/** + * struct mtk_crtc_crc - crc related information + * @ofs: register offset of crc + * @rst_ofs: register offset of crc reset + * @rst_msk: register mask of crc reset + * @cnt: count of crc + * @va: pointer to the start of crc array + * @pa: physical address of the crc for gce to access + * @cmdq_event: the event to trigger the cmdq + * @cmdq_reg: address of the register that cmdq is going to access + * @cmdq_client: handler to control cmdq (mbox channel, thread ...etc.) + * @cmdq_handle: cmdq packet to store the commands + */ +struct mtk_crtc_crc { + const u32 *ofs; + u32 rst_ofs; + u32 rst_msk; + size_t cnt; + u32 *va; +#if IS_REACHABLE(CONFIG_MTK_CMDQ) + dma_addr_t pa; + u32 cmdq_event; + struct cmdq_client_reg *cmdq_reg; + struct cmdq_client cmdq_client; + struct cmdq_pkt cmdq_handle; +#endif +}; + void mtk_crtc_commit(struct drm_crtc *crtc); int mtk_crtc_create(struct drm_device *drm_dev, const unsigned int *path, unsigned int path_len, int priv_data_index, @@ -25,4 +53,14 @@ void mtk_crtc_async_update(struct drm_crtc *crtc, struct drm_plane *plane, struct drm_atomic_state *plane_state); struct device *mtk_crtc_dma_dev_get(struct drm_crtc *crtc); +void mtk_crtc_init_crc(struct mtk_crtc_crc *crc, const u32 *crc_offset_table, + size_t crc_count, u32 reset_offset, u32 reset_mask); +void mtk_crtc_read_crc(struct mtk_crtc_crc *crc, void __iomem *reg); +void mtk_crtc_destroy_crc(struct mtk_crtc_crc *crc); +#if IS_REACHABLE(CONFIG_MTK_CMDQ) +void mtk_crtc_create_crc_cmdq(struct device *dev, struct mtk_crtc_crc *crc); +void mtk_crtc_start_crc_cmdq(struct mtk_crtc_crc *crc); +void mtk_crtc_stop_crc_cmdq(struct mtk_crtc_crc *crc); +#endif + #endif /* MTK_CRTC_H */ diff --git a/drivers/gpu/drm/mediatek/mtk_ddp_comp.h b/drivers/gpu/drm/mediatek/mtk_ddp_comp.h index f7fe2e08dc8e2..b9c79e740abe0 100644 --- a/drivers/gpu/drm/mediatek/mtk_ddp_comp.h +++ b/drivers/gpu/drm/mediatek/mtk_ddp_comp.h @@ -88,6 +88,9 @@ struct mtk_ddp_comp_funcs { void (*remove)(struct device *dev, struct mtk_mutex *mutex); unsigned int (*encoder_index)(struct device *dev); enum drm_mode_status (*mode_valid)(struct device *dev, const struct drm_display_mode *mode); + size_t (*crc_cnt)(struct device *dev); + u32 *(*crc_entry)(struct device *dev); + void (*crc_read)(struct device *dev); }; struct mtk_ddp_comp {