[PATCH 2/8] i2c: mediatek: Dump i2c/dma register when a timeout occurs

From: Kewei Xu
Date: Wed Jul 14 2021 - 22:30:22 EST


When a timeout error occurs in i2c transter, it is usually related
to the i2c/dma IP hardware configuration. Therefore, the purpose of
this patch is to dump the key register values of i2c/dma when a
timeout occurs in i2c for debugging.

Signed-off-by: Kewei Xu <kewei.xu@xxxxxxxxxxxx>
---
drivers/i2c/busses/i2c-mt65xx.c | 95 ++++++++++++++++++++++++++++++++++++++++-
1 file changed, 94 insertions(+), 1 deletion(-)

diff --git a/drivers/i2c/busses/i2c-mt65xx.c b/drivers/i2c/busses/i2c-mt65xx.c
index 5ddfa4e..64acd96 100644
--- a/drivers/i2c/busses/i2c-mt65xx.c
+++ b/drivers/i2c/busses/i2c-mt65xx.c
@@ -125,6 +125,7 @@ enum I2C_REGS_OFFSET {
OFFSET_HS,
OFFSET_SOFTRESET,
OFFSET_DCM_EN,
+ OFFSET_MULTI_DMA,
OFFSET_PATH_DIR,
OFFSET_DEBUGSTAT,
OFFSET_DEBUGCTRL,
@@ -192,6 +193,7 @@ enum I2C_REGS_OFFSET {
[OFFSET_TRANSFER_LEN_AUX] = 0x44,
[OFFSET_CLOCK_DIV] = 0x48,
[OFFSET_SOFTRESET] = 0x50,
+ [OFFSET_MULTI_DMA] = 0x84,
[OFFSET_SCL_MIS_COMP_POINT] = 0x90,
[OFFSET_DEBUGSTAT] = 0xe0,
[OFFSET_DEBUGCTRL] = 0xe8,
@@ -828,6 +830,96 @@ static int mtk_i2c_set_speed(struct mtk_i2c *i2c, unsigned int parent_clk)
return 0;
}

+static void i2c_dump_register(struct mtk_i2c *i2c)
+{
+ dev_err(i2c->dev, "SLAVE_ADDR[0x%x]: 0x%x, INTR_MASK[0x%x]: 0x%x\n",
+ OFFSET_SLAVE_ADDR,
+ (mtk_i2c_readw(i2c, OFFSET_SLAVE_ADDR)),
+ OFFSET_INTR_MASK,
+ (mtk_i2c_readw(i2c, OFFSET_INTR_MASK)));
+ dev_err(i2c->dev, "INTR_STAT[0x%x]: 0x%x, CONTROL[0x%x]: 0x%x\n",
+ OFFSET_INTR_STAT,
+ (mtk_i2c_readw(i2c, OFFSET_INTR_STAT)),
+ OFFSET_CONTROL,
+ (mtk_i2c_readw(i2c, OFFSET_CONTROL)));
+ dev_err(i2c->dev, "TRANSFER_LEN[0x%x]: 0x%x, TRANSAC_LEN[0x%x]: 0x%x\n",
+ OFFSET_TRANSFER_LEN,
+ (mtk_i2c_readw(i2c, OFFSET_TRANSFER_LEN)),
+ OFFSET_TRANSAC_LEN,
+ (mtk_i2c_readw(i2c, OFFSET_TRANSAC_LEN)));
+ dev_err(i2c->dev, "DELAY_LEN[0x%x]: 0x%x, HTIMING[0x%x]: 0x%x\n",
+ OFFSET_DELAY_LEN,
+ (mtk_i2c_readw(i2c, OFFSET_DELAY_LEN)),
+ OFFSET_TIMING,
+ (mtk_i2c_readw(i2c, OFFSET_TIMING)));
+ dev_err(i2c->dev, "OFFSET_START[0x%x]: 0x%x\n",
+ OFFSET_START,
+ mtk_i2c_readw(i2c, OFFSET_START));
+ dev_err(i2c->dev, "OFFSET_EXT_CONF[0x%x]: 0x%x\n",
+ OFFSET_EXT_CONF,
+ mtk_i2c_readw(i2c, OFFSET_EXT_CONF));
+ dev_err(i2c->dev, "OFFSET_HS[0x%x]: 0x%x\n",
+ OFFSET_HS,
+ mtk_i2c_readw(i2c, OFFSET_HS));
+ dev_err(i2c->dev, "OFFSET_IO_CONFIG[0x%x]: 0x%x\n",
+ OFFSET_IO_CONFIG,
+ mtk_i2c_readw(i2c, OFFSET_IO_CONFIG));
+ dev_err(i2c->dev, "OFFSET_FIFO_ADDR_CLR[0x%x]: 0x%x\n",
+ OFFSET_FIFO_ADDR_CLR,
+ mtk_i2c_readw(i2c, OFFSET_FIFO_ADDR_CLR));
+ dev_err(i2c->dev, "TRANSFER_LEN_AUX[0x%x]: 0x%x\n",
+ OFFSET_TRANSFER_LEN_AUX,
+ mtk_i2c_readw(i2c, OFFSET_TRANSFER_LEN_AUX));
+ dev_err(i2c->dev, "CLOCK_DIV[0x%x]: 0x%x\n",
+ OFFSET_CLOCK_DIV,
+ mtk_i2c_readw(i2c, OFFSET_CLOCK_DIV));
+ dev_err(i2c->dev, "FIFO_STAT[0x%x]: 0x%x, FIFO_THRESH[0x%x]: 0x%x\n",
+ OFFSET_FIFO_STAT,
+ mtk_i2c_readw(i2c, OFFSET_FIFO_STAT),
+ OFFSET_FIFO_THRESH,
+ mtk_i2c_readw(i2c, OFFSET_FIFO_THRESH));
+ dev_err(i2c->dev, "DCM_EN[0x%x] 0x%x\n",
+ OFFSET_DCM_EN,
+ mtk_i2c_readw(i2c, OFFSET_DCM_EN));
+ dev_err(i2c->dev, "DEBUGSTAT[0x%x]: 0x%x, DEBUGCTRL[0x%x]: 0x%x\n",
+ OFFSET_DEBUGSTAT,
+ (mtk_i2c_readw(i2c, OFFSET_DEBUGSTAT)),
+ OFFSET_DEBUGCTRL,
+ (mtk_i2c_readw(i2c, OFFSET_DEBUGCTRL)));
+
+ if (i2c->dev_comp->regs == mt_i2c_regs_v2) {
+ dev_err(i2c->dev, "OFFSET_LTIMING[0x%x]: 0x%x\n",
+ OFFSET_LTIMING,
+ mtk_i2c_readw(i2c, OFFSET_LTIMING));
+ dev_err(i2c->dev, "MULTI_DMA[0x%x]: 0x%x\n",
+ OFFSET_MULTI_DMA,
+ (mtk_i2c_readw(i2c, OFFSET_MULTI_DMA)));
+ }
+
+ dev_err(i2c->dev, "OFFSET_INT_FLAG = 0x%x\n",
+ readl(i2c->pdmabase + OFFSET_INT_FLAG));
+ dev_err(i2c->dev, "OFFSET_INT_EN = 0x%x\n",
+ readl(i2c->pdmabase + OFFSET_INT_EN));
+ dev_err(i2c->dev, "OFFSET_EN = 0x%x\n",
+ readl(i2c->pdmabase + OFFSET_EN));
+ dev_err(i2c->dev, "OFFSET_RST = 0x%x\n",
+ readl(i2c->pdmabase + OFFSET_RST));
+ dev_err(i2c->dev, "OFFSET_CON = 0x%x\n",
+ readl(i2c->pdmabase + OFFSET_CON));
+ dev_err(i2c->dev, "OFFSET_TX_MEM_ADDR = 0x%x\n",
+ readl(i2c->pdmabase + OFFSET_TX_MEM_ADDR));
+ dev_err(i2c->dev, "OFFSET_RX_MEM_ADDR = 0x%x\n",
+ readl(i2c->pdmabase + OFFSET_RX_MEM_ADDR));
+ dev_err(i2c->dev, "OFFSET_TX_LEN = 0x%x\n",
+ readl(i2c->pdmabase + OFFSET_TX_LEN));
+ dev_err(i2c->dev, "OFFSET_RX_LEN = 0x%x\n",
+ readl(i2c->pdmabase + OFFSET_RX_LEN));
+ dev_err(i2c->dev, "OFFSET_TX_4G_MODE = 0x%x\n",
+ readl(i2c->pdmabase + OFFSET_TX_4G_MODE));
+ dev_err(i2c->dev, "OFFSET_RX_4G_MODE = 0x%x\n",
+ readl(i2c->pdmabase + OFFSET_RX_4G_MODE));
+}
+
static int mtk_i2c_do_transfer(struct mtk_i2c *i2c, struct i2c_msg *msgs,
int num, int left_num)
{
@@ -1034,7 +1126,8 @@ static int mtk_i2c_do_transfer(struct mtk_i2c *i2c, struct i2c_msg *msgs,
}

if (ret == 0) {
- dev_dbg(i2c->dev, "addr: %x, transfer timeout\n", msgs->addr);
+ dev_err(i2c->dev, "addr: %x, transfer timeout\n", msgs->addr);
+ i2c_dump_register(i2c);
mtk_i2c_init_hw(i2c);
return -ETIMEDOUT;
}
--
1.9.1