[PATCH v2 1/3] media: verisilicon: stop the VEPU1 JPEG encoder after an unfinished frame

[Sergei Khomenkov via B4 Relay <devnull+shomenkow.gmail.com@kernel.org>]

From: Sergei Khomenkov <shomenkow@gmail.com>

When the JPEG stream reaches the stream buffer limit, the H1 raises a
buffer-full interrupt and pauses with the enable bit of H1_REG_ENC_CTRL
still set. rockchip_vpu1_vepu_irq() does not stop it, so the next job is
programmed into the paused encoder and times out.

Clear only the enable bit when an interrupt does not report a finished
frame, and warn (rate limited) about each fault bit that is set, as
hantro_g2_irq() does.

Found with an LLM coding assistant while porting mainline Linux to a
Rockchip RK3026 board; the assistant also drafted this change. Tested
on that board, with the next patch applied: a frame that does not fit
now ends with the ERROR flag and one interrupt, and the following jobs
complete. Not tested on other SoCs.

Fixes: 775fec69008d ("media: add Rockchip VPU JPEG encoder driver")
Cc: stable@vger.kernel.org
Signed-off-by: Sergei Khomenkov <shomenkow@gmail.com>
---
 drivers/media/platform/verisilicon/hantro_h1_regs.h  |  4 ++++
 drivers/media/platform/verisilicon/rockchip_vpu_hw.c | 18 ++++++++++++++++++
 2 files changed, 22 insertions(+)

diff --git a/drivers/media/platform/verisilicon/hantro_h1_regs.h b/drivers/media/platform/verisilicon/hantro_h1_regs.h
index 8650cc489392..a7f18683dac1 100644
--- a/drivers/media/platform/verisilicon/hantro_h1_regs.h
+++ b/drivers/media/platform/verisilicon/hantro_h1_regs.h
@@ -11,6 +11,10 @@
 
 /* Encoder registers. */
 #define H1_REG_INTERRUPT				0x004
+#define     H1_REG_INTERRUPT_TIMEOUT			BIT(6)
+#define     H1_REG_INTERRUPT_BUFFER_FULL		BIT(5)
+#define     H1_REG_INTERRUPT_RESET			BIT(4)
+#define     H1_REG_INTERRUPT_BUS_ERROR			BIT(3)
 #define     H1_REG_INTERRUPT_FRAME_RDY			BIT(2)
 #define     H1_REG_INTERRUPT_DIS_BIT			BIT(1)
 #define     H1_REG_INTERRUPT_BIT			BIT(0)
diff --git a/drivers/media/platform/verisilicon/rockchip_vpu_hw.c b/drivers/media/platform/verisilicon/rockchip_vpu_hw.c
index 02673be9878e..d201b058e5e8 100644
--- a/drivers/media/platform/verisilicon/rockchip_vpu_hw.c
+++ b/drivers/media/platform/verisilicon/rockchip_vpu_hw.c
@@ -376,6 +376,24 @@ static irqreturn_t rockchip_vpu1_vepu_irq(int irq, void *dev_id)
 	state = (status & H1_REG_INTERRUPT_FRAME_RDY) ?
 		VB2_BUF_STATE_DONE : VB2_BUF_STATE_ERROR;
 
+	if (status & H1_REG_INTERRUPT_BUFFER_FULL)
+		dev_warn_ratelimited(vpu->dev, "stream buffer full\n");
+	if (status & H1_REG_INTERRUPT_BUS_ERROR)
+		dev_warn_ratelimited(vpu->dev, "bus error detected\n");
+	if (status & H1_REG_INTERRUPT_TIMEOUT)
+		dev_warn_ratelimited(vpu->dev, "frame encode timed out\n");
+	if (status & H1_REG_INTERRUPT_RESET)
+		dev_warn_ratelimited(vpu->dev, "encoder reset\n");
+
+	/* After a buffer full the encoder pauses, still enabled: stop it. */
+	if (!(status & H1_REG_INTERRUPT_FRAME_RDY)) {
+		u32 ctrl = vepu_read(vpu, H1_REG_ENC_CTRL);
+
+		if (ctrl & H1_REG_ENC_CTRL_EN_BIT)
+			vepu_write(vpu, ctrl & ~H1_REG_ENC_CTRL_EN_BIT,
+				   H1_REG_ENC_CTRL);
+	}
+
 	vepu_write(vpu, 0, H1_REG_INTERRUPT);
 	vepu_write(vpu, 0, H1_REG_AXI_CTRL);
 

-- 
2.53.0