[PATCH] i3c: master: dw-i3c-master: Add HDR-DDR support to Designware Controller.

[PATCH] i3c: master: dw-i3c-master: Add HDR-DDR support to Designware Controller.

[Dineshkumar Parameswaran]

Implement HDR-DDR transfer support for the DesignWare Controller.
Only support for private transfers and does not support sending CCC
commands in HDR mode.

Key differences:
- Sends ENTHDR CCC for entering to HDR-DDR mode before sending data.
To do that we are setting the ENTHDR in controller cmd. Sets the speed
to HDR_DDR_SPEED(6) to do data transfer in HDR-DDR mode.
- HDR exit pattern must be sent instead of send a stop after transfer
completion.

Signed-off-by: Dineshkumar Parameswaran <parame@synopsys.com>
---
 drivers/i3c/master/dw-i3c-master.c | 7 +++++++
 1 file changed, 7 insertions(+)

diff --git a/drivers/i3c/master/dw-i3c-master.c b/drivers/i3c/master/dw-i3c-master.c
index 05584ddaf104..58c54746bbe5 100644
--- a/drivers/i3c/master/dw-i3c-master.c
+++ b/drivers/i3c/master/dw-i3c-master.c
@@ -232,6 +232,8 @@
 #define I3C_BUS_I2C_FMP_TLOW_MIN_NS	500
 #define I3C_BUS_THIGH_MAX_NS		41
 
+#define DW_I3C_HDR_DDR_SPEED	6
+
 #define XFER_TIMEOUT (msecs_to_jiffies(1000))
 #define RPM_AUTOSUSPEND_TIMEOUT 1000 /* ms */
 
@@ -1017,6 +1019,11 @@ static int dw_i3c_master_i3c_xfers(struct i3c_dev_desc *dev,
 			       COMMAND_PORT_DEV_INDEX(data->index) |
 			       COMMAND_PORT_ROC;
 
+		if (mode == I3C_HDR_DDR)
+			cmd->cmd_lo |= COMMAND_PORT_CP |
+				COMMAND_PORT_CMD(I3C_CCC_ENTHDR(0)) |
+				COMMAND_PORT_SPEED(DW_I3C_HDR_DDR_SPEED);
+
 		if (i == (i3c_nxfers - 1))
 			cmd->cmd_lo |= COMMAND_PORT_TOC;
 	}
-- 
2.34.1

[PATCH v2] i3c: master: dw-i3c-master: Add HDR-DDR support to Designware Controller.

[Dineshkumar Parameswaran]

Implement HDR-DDR transfer support for the DesignWare Controller.
Only support for private transfers and does not support sending CCC
commands in HDR mode.

Key differences:
- Sends ENTHDR CCC for entering to HDR-DDR mode before sending data.
To do that we are setting the ENTHDR in controller cmd. Sets the speed
to HDR_DDR_SPEED(6) to do data transfer in HDR-DDR mode.
- HDR exit pattern must be sent instead of send a stop after transfer
completion.

Signed-off-by: Dineshkumar Parameswaran <parame@synopsys.com>

---
changes in v2:
- Add HDR-DDR capability advertisement in dw_i3c_master_bus_init()
- ENTHDR0 CCC is generated by the hardware. No need to put that in the
  command.
- Fix the speed field corruption in COMMAND_PORT_SPEED.

 drivers/i3c/master/dw-i3c-master.c | 17 +++++++++++++----
 1 file changed, 13 insertions(+), 4 deletions(-)

diff --git a/drivers/i3c/master/dw-i3c-master.c b/drivers/i3c/master/dw-i3c-master.c
index 05584ddaf104..149982a05477 100644
--- a/drivers/i3c/master/dw-i3c-master.c
+++ b/drivers/i3c/master/dw-i3c-master.c
@@ -232,6 +232,8 @@
 #define I3C_BUS_I2C_FMP_TLOW_MIN_NS	500
 #define I3C_BUS_THIGH_MAX_NS		41
 
+#define DW_I3C_HDR_DDR_SPEED	6
+
 #define XFER_TIMEOUT (msecs_to_jiffies(1000))
 #define RPM_AUTOSUSPEND_TIMEOUT 1000 /* ms */
 
@@ -726,6 +728,8 @@ static int dw_i3c_master_bus_init(struct i3c_master_controller *m)
 	memset(&info, 0, sizeof(info));
 	info.dyn_addr = ret;
 
+	info.hdr_cap = I3C_CCC_HDR_MODE(I3C_HDR_DDR);
+
 	ret = i3c_master_set_info(&master->base, &info);
 	if (ret)
 		goto rpm_out;
@@ -1003,20 +1007,25 @@ static int dw_i3c_master_i3c_xfers(struct i3c_dev_desc *dev,
 		if (i3c_xfers[i].rnw) {
 			cmd->rx_buf = i3c_xfers[i].data.in;
 			cmd->rx_len = i3c_xfers[i].len;
-			cmd->cmd_lo = COMMAND_PORT_READ_TRANSFER |
-				      COMMAND_PORT_SPEED(dev->info.max_read_ds);
+			cmd->cmd_lo = COMMAND_PORT_READ_TRANSFER;
 
 		} else {
 			cmd->tx_buf = i3c_xfers[i].data.out;
 			cmd->tx_len = i3c_xfers[i].len;
-			cmd->cmd_lo =
-				COMMAND_PORT_SPEED(dev->info.max_write_ds);
 		}
 
 		cmd->cmd_lo |= COMMAND_PORT_TID(i) |
 			       COMMAND_PORT_DEV_INDEX(data->index) |
 			       COMMAND_PORT_ROC;
 
+		if (mode == I3C_HDR_DDR)
+			cmd->cmd_lo |= COMMAND_PORT_CP |
+				COMMAND_PORT_SPEED(DW_I3C_HDR_DDR_SPEED);
+		else
+			cmd->cmd_lo |= (i3c_xfers[i].rnw) ?
+				COMMAND_PORT_SPEED(dev->info.max_read_ds) :
+				COMMAND_PORT_SPEED(dev->info.max_write_ds);
+
 		if (i == (i3c_nxfers - 1))
 			cmd->cmd_lo |= COMMAND_PORT_TOC;
 	}
-- 
2.34.1

Re: [PATCH v2] i3c: master: dw-i3c-master: Add HDR-DDR support to Designware Controller.

[Frank Li]

On Sun, Nov 01, 2026 at 06:22:43AM +0530, Dineshkumar Parameswaran wrote:
> Implement HDR-DDR transfer support for the DesignWare Controller.
> Only support for private transfers and does not support sending CCC
> commands in HDR mode.
>
> Key differences:
> - Sends ENTHDR CCC for entering to HDR-DDR mode before sending data.
> To do that we are setting the ENTHDR in controller cmd. Sets the speed

Send ENTHDR CCC before sending data by setting the ENTHDR in controller cmd.

> to HDR_DDR_SPEED(6) to do data transfer in HDR-DDR mode.
> - HDR exit pattern must be sent instead of send a stop after transfer
> completion.

Send HDR exit pattern instead of STOP after transfer completion.

>
> Signed-off-by: Dineshkumar Parameswaran <parame@synopsys.com>
>
> ---

Do NOT post new version at old thread, which will cause patchwork and other
tools.

> changes in v2:
> - Add HDR-DDR capability advertisement in dw_i3c_master_bus_init()
> - ENTHDR0 CCC is generated by the hardware. No need to put that in the
>   command.
> - Fix the speed field corruption in COMMAND_PORT_SPEED.
>
>  drivers/i3c/master/dw-i3c-master.c | 17 +++++++++++++----
>  1 file changed, 13 insertions(+), 4 deletions(-)
>
> diff --git a/drivers/i3c/master/dw-i3c-master.c b/drivers/i3c/master/dw-i3c-master.c
> index 05584ddaf104..149982a05477 100644
> --- a/drivers/i3c/master/dw-i3c-master.c
> +++ b/drivers/i3c/master/dw-i3c-master.c
> @@ -232,6 +232,8 @@
>  #define I3C_BUS_I2C_FMP_TLOW_MIN_NS	500
>  #define I3C_BUS_THIGH_MAX_NS		41
>
> +#define DW_I3C_HDR_DDR_SPEED	6
> +
>  #define XFER_TIMEOUT (msecs_to_jiffies(1000))
>  #define RPM_AUTOSUSPEND_TIMEOUT 1000 /* ms */
>
> @@ -726,6 +728,8 @@ static int dw_i3c_master_bus_init(struct i3c_master_controller *m)
>  	memset(&info, 0, sizeof(info));
>  	info.dyn_addr = ret;
>
> +	info.hdr_cap = I3C_CCC_HDR_MODE(I3C_HDR_DDR);
> +
>  	ret = i3c_master_set_info(&master->base, &info);
>  	if (ret)
>  		goto rpm_out;
> @@ -1003,20 +1007,25 @@ static int dw_i3c_master_i3c_xfers(struct i3c_dev_desc *dev,
>  		if (i3c_xfers[i].rnw) {

At HDR mode, rnw is u8 command, bit 7 indicate read or write. And where
you send cmd?

Frank

>  			cmd->rx_buf = i3c_xfers[i].data.in;
>  			cmd->rx_len = i3c_xfers[i].len;
> -			cmd->cmd_lo = COMMAND_PORT_READ_TRANSFER |
> -				      COMMAND_PORT_SPEED(dev->info.max_read_ds);
> +			cmd->cmd_lo = COMMAND_PORT_READ_TRANSFER;
>
>  		} else {
>  			cmd->tx_buf = i3c_xfers[i].data.out;
>  			cmd->tx_len = i3c_xfers[i].len;
> -			cmd->cmd_lo =
> -				COMMAND_PORT_SPEED(dev->info.max_write_ds);
>  		}
>
>  		cmd->cmd_lo |= COMMAND_PORT_TID(i) |
>  			       COMMAND_PORT_DEV_INDEX(data->index) |
>  			       COMMAND_PORT_ROC;
>
> +		if (mode == I3C_HDR_DDR)
> +			cmd->cmd_lo |= COMMAND_PORT_CP |
> +				COMMAND_PORT_SPEED(DW_I3C_HDR_DDR_SPEED);
> +		else
> +			cmd->cmd_lo |= (i3c_xfers[i].rnw) ?
> +				COMMAND_PORT_SPEED(dev->info.max_read_ds) :
> +				COMMAND_PORT_SPEED(dev->info.max_write_ds);
> +
>  		if (i == (i3c_nxfers - 1))
>  			cmd->cmd_lo |= COMMAND_PORT_TOC;
>  	}
> --
> 2.34.1
>

[PATCH v3] i3c: master: dw-i3c-master: Add HDR-DDR support to Designware Controller.

[Dineshkumar Parameswaran]

Implement HDR-DDR transfer support for the DesignWare Controller.
Only support for private transfers and does not support sending CCC
commands in HDR mode.

Key differences:
- Sets the speed to HDR_DDR_SPEED(6) and COMMAND_PORT_CP to do
data transfer in HDR-DDR mode. Hardware will generate the ENTHDR0
based on this.
- HDR exit pattern will generated from the hardware when it sees
the TOC on HDR-DDR mode.

Signed-off-by: Dineshkumar Parameswaran <parame@synopsys.com>
---
changes in v3:
- Updated commit message.
- Sets the HDR-DDR Read and Write based on cmd.

 drivers/i3c/master/dw-i3c-master.c | 29 ++++++++++++++++++++++++-----
 1 file changed, 24 insertions(+), 5 deletions(-)

diff --git a/drivers/i3c/master/dw-i3c-master.c b/drivers/i3c/master/dw-i3c-master.c
index 05584ddaf104..d4a0b1d316a9 100644
--- a/drivers/i3c/master/dw-i3c-master.c
+++ b/drivers/i3c/master/dw-i3c-master.c
@@ -65,6 +65,8 @@
 #define COMMAND_PORT_DEV_COUNT(x)	(((x) << 21) & GENMASK(25, 21))
 #define COMMAND_PORT_ADDR_ASSGN_CMD	0x03
 
+#define HDR_DDR_CMD_READ		0x80
+
 #define RESPONSE_QUEUE_PORT		0x10
 #define RESPONSE_PORT_ERR_STATUS(x)	(((x) & GENMASK(31, 28)) >> 28)
 #define RESPONSE_NO_ERROR		0
@@ -232,6 +234,8 @@
 #define I3C_BUS_I2C_FMP_TLOW_MIN_NS	500
 #define I3C_BUS_THIGH_MAX_NS		41
 
+#define DW_I3C_HDR_DDR_SPEED	6
+
 #define XFER_TIMEOUT (msecs_to_jiffies(1000))
 #define RPM_AUTOSUSPEND_TIMEOUT 1000 /* ms */
 
@@ -381,6 +385,11 @@ static void dw_i3c_master_read_ibi_fifo(struct dw_i3c_master *master,
 	i3c_readl_fifo(master->regs + IBI_QUEUE_STATUS, bytes, nbytes);
 }
 
+static bool dw_cmd_is_read(u32 rnw_cmd, enum i3c_xfer_mode mode)
+{
+	return (mode == I3C_HDR_DDR) ? (rnw_cmd & HDR_DDR_CMD_READ) : rnw_cmd;
+}
+
 static struct dw_i3c_xfer *
 dw_i3c_master_alloc_xfer(struct dw_i3c_master *master, unsigned int ncmds)
 {
@@ -726,6 +735,8 @@ static int dw_i3c_master_bus_init(struct i3c_master_controller *m)
 	memset(&info, 0, sizeof(info));
 	info.dyn_addr = ret;
 
+	info.hdr_cap = I3C_CCC_HDR_MODE(I3C_HDR_DDR);
+
 	ret = i3c_master_set_info(&master->base, &info);
 	if (ret)
 		goto rpm_out;
@@ -995,28 +1006,36 @@ static int dw_i3c_master_i3c_xfers(struct i3c_dev_desc *dev,
 	}
 
 	for (i = 0; i < i3c_nxfers; i++) {
+		u32 rnw_cmd = (mode == I3C_SDR) ? i3c_xfers[i].rnw : i3c_xfers[i].cmd;
+		bool rnw = dw_cmd_is_read(rnw_cmd, mode);
 		struct dw_i3c_cmd *cmd = &xfer->cmds[i];
 
 		cmd->cmd_hi = COMMAND_PORT_ARG_DATA_LEN(i3c_xfers[i].len) |
 			COMMAND_PORT_TRANSFER_ARG;
 
-		if (i3c_xfers[i].rnw) {
+		if (rnw) {
 			cmd->rx_buf = i3c_xfers[i].data.in;
 			cmd->rx_len = i3c_xfers[i].len;
-			cmd->cmd_lo = COMMAND_PORT_READ_TRANSFER |
-				      COMMAND_PORT_SPEED(dev->info.max_read_ds);
+			cmd->cmd_lo = COMMAND_PORT_READ_TRANSFER;
 
 		} else {
 			cmd->tx_buf = i3c_xfers[i].data.out;
 			cmd->tx_len = i3c_xfers[i].len;
-			cmd->cmd_lo =
-				COMMAND_PORT_SPEED(dev->info.max_write_ds);
 		}
 
 		cmd->cmd_lo |= COMMAND_PORT_TID(i) |
 			       COMMAND_PORT_DEV_INDEX(data->index) |
 			       COMMAND_PORT_ROC;
 
+		if (mode == I3C_HDR_DDR) {
+			cmd->cmd_lo |= COMMAND_PORT_CMD(rnw_cmd) | COMMAND_PORT_CP |
+				COMMAND_PORT_SPEED(DW_I3C_HDR_DDR_SPEED);
+		} else {
+			cmd->cmd_lo |= (i3c_xfers[i].rnw) ?
+				COMMAND_PORT_SPEED(dev->info.max_read_ds) :
+				COMMAND_PORT_SPEED(dev->info.max_write_ds);
+		}
+
 		if (i == (i3c_nxfers - 1))
 			cmd->cmd_lo |= COMMAND_PORT_TOC;
 	}
-- 
2.34.1