drm/mediatek: Add AFBC support to Mediatek DRM driver

Tested on MT8195 and confirmed both correct video output and improved DRAM
bandwidth performance.

Signed-off-by: Justin Green <greenjustin@chromium.org>
Reviewed-by: AngeloGioacchino Del Regno <angelogioacchino.delregno@collabora.com>
Link: https://patchwork.kernel.org/project/linux-mediatek/patch/20221116193335.36320-1-greenjustin@google.com/
Signed-off-by: Chun-Kuang Hu <chunkuang.hu@kernel.org>

1 files changed, 44 insertions, 2 deletions

diff --git a/drivers/gpu/drm/mediatek/mtk_disp_ovl.c b/drivers/gpu/drm/mediatek/mtk_disp_ovl.c
index 002b0f6cae1a..5a60c3b504ff 100644
--- a/drivers/gpu/drm/mediatek/mtk_disp_ovl.c
+++ b/drivers/gpu/drm/mediatek/mtk_disp_ovl.c
@@ -29,17 +29,22 @@
 #define DISP_REG_OVL_DATAPATH_CON		0x0024
 #define OVL_LAYER_SMI_ID_EN				BIT(0)
 #define OVL_BGCLR_SEL_IN				BIT(2)
+#define OVL_LAYER_AFBC_EN(n)				BIT(4+n)
 #define DISP_REG_OVL_ROI_BGCLR			0x0028
 #define DISP_REG_OVL_SRC_CON			0x002c
 #define DISP_REG_OVL_CON(n)			(0x0030 + 0x20 * (n))
 #define DISP_REG_OVL_SRC_SIZE(n)		(0x0038 + 0x20 * (n))
 #define DISP_REG_OVL_OFFSET(n)			(0x003c + 0x20 * (n))
+#define DISP_REG_OVL_PITCH_MSB(n)		(0x0040 + 0x20 * (n))
+#define OVL_PITCH_MSB_2ND_SUBBUF			BIT(16)
 #define DISP_REG_OVL_PITCH(n)			(0x0044 + 0x20 * (n))
 #define DISP_REG_OVL_RDMA_CTRL(n)		(0x00c0 + 0x20 * (n))
 #define DISP_REG_OVL_RDMA_GMC(n)		(0x00c8 + 0x20 * (n))
 #define DISP_REG_OVL_ADDR_MT2701		0x0040
 #define DISP_REG_OVL_ADDR_MT8173		0x0f40
 #define DISP_REG_OVL_ADDR(ovl, n)		((ovl)->data->addr + 0x20 * (n))
+#define DISP_REG_OVL_HDR_ADDR(ovl, n)		((ovl)->data->addr + 0x20 * (n) + 0x04)
+#define DISP_REG_OVL_HDR_PITCH(ovl, n)		((ovl)->data->addr + 0x20 * (n) + 0x08)
 
 #define GMC_THRESHOLD_BITS	16
 #define GMC_THRESHOLD_HIGH	((1 << GMC_THRESHOLD_BITS) / 4)
@@ -67,6 +72,7 @@ struct mtk_disp_ovl_data {
 	unsigned int layer_nr;
 	bool fmt_rgb565_is_0;
 	bool smi_id_en;
+	bool supports_afbc;
 };
 
 /*
@@ -172,7 +178,14 @@ void mtk_ovl_stop(struct device *dev)
 		reg = reg & ~OVL_LAYER_SMI_ID_EN;
 		writel_relaxed(reg, ovl->regs + DISP_REG_OVL_DATAPATH_CON);
 	}
+}
 
+static void mtk_ovl_set_afbc(struct mtk_disp_ovl *ovl, struct cmdq_pkt *cmdq_pkt,
+			     int idx, bool enabled)
+{
+	mtk_ddp_write_mask(cmdq_pkt, enabled ? OVL_LAYER_AFBC_EN(idx) : 0,
+			   &ovl->cmdq_reg, ovl->regs,
+			   DISP_REG_OVL_DATAPATH_CON, OVL_LAYER_AFBC_EN(idx));
 }
 
 void mtk_ovl_config(struct device *dev, unsigned int w,
@@ -310,11 +323,23 @@ void mtk_ovl_layer_config(struct device *dev, unsigned int idx,
 	struct mtk_disp_ovl *ovl = dev_get_drvdata(dev);
 	struct mtk_plane_pending_state *pending = &state->pending;
 	unsigned int addr = pending->addr;
-	unsigned int pitch = pending->pitch & 0xffff;
+	unsigned int hdr_addr = pending->hdr_addr;
+	unsigned int pitch = pending->pitch;
+	unsigned int hdr_pitch = pending->hdr_pitch;
 	unsigned int fmt = pending->format;
 	unsigned int offset = (pending->y << 16) | pending->x;
 	unsigned int src_size = (pending->height << 16) | pending->width;
 	unsigned int con;
+	bool is_afbc = pending->modifier != DRM_FORMAT_MOD_LINEAR;
+	union overlay_pitch {
+		struct split_pitch {
+			u16 lsb;
+			u16 msb;
+		} split_pitch;
+		u32 pitch;
+	} overlay_pitch;
+
+	overlay_pitch.pitch = pitch;
 
 	if (!pending->enable) {
 		mtk_ovl_layer_off(dev, idx, cmdq_pkt);
@@ -335,9 +360,12 @@ void mtk_ovl_layer_config(struct device *dev, unsigned int idx,
 		addr += pending->pitch - 1;
 	}
 
+	if (ovl->data->supports_afbc)
+		mtk_ovl_set_afbc(ovl, cmdq_pkt, idx, is_afbc);
+
 	mtk_ddp_write_relaxed(cmdq_pkt, con, &ovl->cmdq_reg, ovl->regs,
 			      DISP_REG_OVL_CON(idx));
-	mtk_ddp_write_relaxed(cmdq_pkt, pitch, &ovl->cmdq_reg, ovl->regs,
+	mtk_ddp_write_relaxed(cmdq_pkt, overlay_pitch.split_pitch.lsb, &ovl->cmdq_reg, ovl->regs,
 			      DISP_REG_OVL_PITCH(idx));
 	mtk_ddp_write_relaxed(cmdq_pkt, src_size, &ovl->cmdq_reg, ovl->regs,
 			      DISP_REG_OVL_SRC_SIZE(idx));
@@ -346,6 +374,20 @@ void mtk_ovl_layer_config(struct device *dev, unsigned int idx,
 	mtk_ddp_write_relaxed(cmdq_pkt, addr, &ovl->cmdq_reg, ovl->regs,
 			      DISP_REG_OVL_ADDR(ovl, idx));
 
+	if (is_afbc) {
+		mtk_ddp_write_relaxed(cmdq_pkt, hdr_addr, &ovl->cmdq_reg, ovl->regs,
+				      DISP_REG_OVL_HDR_ADDR(ovl, idx));
+		mtk_ddp_write_relaxed(cmdq_pkt,
+				      OVL_PITCH_MSB_2ND_SUBBUF | overlay_pitch.split_pitch.msb,
+				      &ovl->cmdq_reg, ovl->regs, DISP_REG_OVL_PITCH_MSB(idx));
+		mtk_ddp_write_relaxed(cmdq_pkt, hdr_pitch, &ovl->cmdq_reg, ovl->regs,
+				      DISP_REG_OVL_HDR_PITCH(ovl, idx));
+	} else {
+		mtk_ddp_write_relaxed(cmdq_pkt,
+				      overlay_pitch.split_pitch.msb,
+				      &ovl->cmdq_reg, ovl->regs, DISP_REG_OVL_PITCH_MSB(idx));
+	}
+
 	mtk_ovl_layer_on(dev, idx, cmdq_pkt);
 }