* [PATCH v4 0/4] media: rcar-csi2: Add D-PHY support for V4H
@ 2025-06-12 17:59 Niklas Söderlund
2025-06-12 17:59 ` [PATCH v4 1/4] media: rcar-csi2: Clarify usage of mbps and msps Niklas Söderlund
` (3 more replies)
0 siblings, 4 replies; 6+ messages in thread
From: Niklas Söderlund @ 2025-06-12 17:59 UTC (permalink / raw)
To: Mauro Carvalho Chehab, Geert Uytterhoeven, Sakari Ailus,
Tomi Valkeinen, Laurent Pinchart, linux-media, linux-renesas-soc,
linux-kernel
Cc: Niklas Söderlund
Hello,
This series adds support for CSI-2 D-PHY reception on R-Car Gen4 V4H
devices. Previously only C-PHY reception was supported due lack of
documentation and no hardware to test D-PHY on.
Later revisions of the datasheet (Rev.1.21) describes the start-up
procedure in some detail, and we now have hardware to test on! The
documentation however only sparsely documents the registers involved and
instead mostly document magic values and an order to write them to
register offsets without much documentation.
This series tries to in the extend possible to at least used named
register and use formulas and lookup tables to make some sens of the
magic values. Still most of them comes of a table of magic values in the
datasheet.
Patch 1/4 clears up a unfortunate mix of the name mbps (mega bits per
second) used in the D-PHY context and msps (mega symbols per second)
used in the C-PHY context.
Patch 2/4 and 3/4 prepares for adding D-PHY support by cleaning up
register names and an updated common startup procedure for V4H which
have been revised in later versions of the datasheet since the initial
C-PHY V4H support was added.
Finally patch 4/4 adds D-PHY support.
The work is tested at many different link speed and number of lanes. In
2-lane mode using an IMX219 and in 4-lane mode using IMX462 sensors.
See individual patches for change log.
Niklas Söderlund (4):
media: rcar-csi2: Clarify usage of mbps and msps
media: rcar-csi2: Rework macros to access AFE lanes
media: rcar-csi2: Update start procedure for V4H
media: rcar-csi2: Add D-PHY support for V4H
drivers/media/platform/renesas/rcar-csi2.c | 332 ++++++++++++++++++---
1 file changed, 287 insertions(+), 45 deletions(-)
--
2.49.0
^ permalink raw reply [flat|nested] 6+ messages in thread
* [PATCH v4 1/4] media: rcar-csi2: Clarify usage of mbps and msps
2025-06-12 17:59 [PATCH v4 0/4] media: rcar-csi2: Add D-PHY support for V4H Niklas Söderlund
@ 2025-06-12 17:59 ` Niklas Söderlund
2025-06-12 17:59 ` [PATCH v4 2/4] media: rcar-csi2: Rework macros to access AFE lanes Niklas Söderlund
` (2 subsequent siblings)
3 siblings, 0 replies; 6+ messages in thread
From: Niklas Söderlund @ 2025-06-12 17:59 UTC (permalink / raw)
To: Mauro Carvalho Chehab, Geert Uytterhoeven, Sakari Ailus,
Tomi Valkeinen, Laurent Pinchart, linux-media, linux-renesas-soc,
linux-kernel
Cc: Niklas Söderlund, Laurent Pinchart
The helper function to deal with calculating the link speed is designed
in such a way that it returns the correct type bps (bits per second) for
D-PHY and sps (symbols per second) for C-PHY. And for historical reasons
the function kept the name mbps.
This is confusing, fix it by having the function only deal with bps
values as this is the most common use-case and convert bps to sps in the
only function where it is needed to configure the C-PHY.
Signed-off-by: Niklas Söderlund <niklas.soderlund+renesas@ragnatech.se>
Tested-by: Tomi Valkeinen <tomi.valkeinen+renesas@ideasonboard.com>
Reviewed-by: Tomi Valkeinen <tomi.valkeinen+renesas@ideasonboard.com>
Reviewed-by: Laurent Pinchart <laurent.pinchart+renesas@ideasonboard.com>
---
drivers/media/platform/renesas/rcar-csi2.c | 22 +++++++++++-----------
1 file changed, 11 insertions(+), 11 deletions(-)
diff --git a/drivers/media/platform/renesas/rcar-csi2.c b/drivers/media/platform/renesas/rcar-csi2.c
index 9979de4f6ef1..358e7470befc 100644
--- a/drivers/media/platform/renesas/rcar-csi2.c
+++ b/drivers/media/platform/renesas/rcar-csi2.c
@@ -975,10 +975,6 @@ static int rcsi2_calc_mbps(struct rcar_csi2 *priv, unsigned int bpp,
mbps = div_u64(freq * 2, MEGA);
- /* Adjust for C-PHY, divide by 2.8. */
- if (priv->cphy)
- mbps = div_u64(mbps * 5, 14);
-
return mbps;
}
@@ -1203,9 +1199,13 @@ static int rcsi2_wait_phy_start_v4h(struct rcar_csi2 *priv, u32 match)
return -ETIMEDOUT;
}
-static int rcsi2_c_phy_setting_v4h(struct rcar_csi2 *priv, int msps)
+static int rcsi2_c_phy_setting_v4h(struct rcar_csi2 *priv, int mbps)
{
const struct rcsi2_cphy_setting *conf;
+ int msps;
+
+ /* Adjust for C-PHY symbols, divide by 2.8. */
+ msps = div_u64(mbps * 5, 14);
for (conf = cphy_setting_table_r8a779g0; conf->msps != 0; conf++) {
if (conf->msps > msps)
@@ -1301,7 +1301,7 @@ static int rcsi2_start_receiver_v4h(struct rcar_csi2 *priv,
const struct rcar_csi2_format *format;
const struct v4l2_mbus_framefmt *fmt;
unsigned int lanes;
- int msps;
+ int mbps;
int ret;
/* Use the format on the sink pad to compute the receiver config. */
@@ -1314,9 +1314,9 @@ static int rcsi2_start_receiver_v4h(struct rcar_csi2 *priv,
if (ret)
return ret;
- msps = rcsi2_calc_mbps(priv, format->bpp, lanes);
- if (msps < 0)
- return msps;
+ mbps = rcsi2_calc_mbps(priv, format->bpp, lanes);
+ if (mbps < 0)
+ return mbps;
/* Reset LINK and PHY*/
rcsi2_write(priv, V4H_CSI2_RESETN_REG, 0);
@@ -1352,7 +1352,7 @@ static int rcsi2_start_receiver_v4h(struct rcar_csi2 *priv,
rcsi2_write16(priv, V4H_PPI_RW_COMMON_CFG_REG, 0x0003);
/* C-PHY settings */
- ret = rcsi2_c_phy_setting_v4h(priv, msps);
+ ret = rcsi2_c_phy_setting_v4h(priv, mbps);
if (ret)
return ret;
@@ -1363,7 +1363,7 @@ static int rcsi2_start_receiver_v4h(struct rcar_csi2 *priv,
return 0;
}
-static int rcsi2_d_phy_setting_v4m(struct rcar_csi2 *priv, int data_rate)
+static int rcsi2_d_phy_setting_v4m(struct rcar_csi2 *priv, int mbps)
{
unsigned int timeout;
int ret;
--
2.49.0
^ permalink raw reply related [flat|nested] 6+ messages in thread
* [PATCH v4 2/4] media: rcar-csi2: Rework macros to access AFE lanes
2025-06-12 17:59 [PATCH v4 0/4] media: rcar-csi2: Add D-PHY support for V4H Niklas Söderlund
2025-06-12 17:59 ` [PATCH v4 1/4] media: rcar-csi2: Clarify usage of mbps and msps Niklas Söderlund
@ 2025-06-12 17:59 ` Niklas Söderlund
2025-06-12 17:59 ` [PATCH v4 3/4] media: rcar-csi2: Update start procedure for V4H Niklas Söderlund
2025-06-12 17:59 ` [PATCH v4 4/4] media: rcar-csi2: Add D-PHY support " Niklas Söderlund
3 siblings, 0 replies; 6+ messages in thread
From: Niklas Söderlund @ 2025-06-12 17:59 UTC (permalink / raw)
To: Mauro Carvalho Chehab, Geert Uytterhoeven, Sakari Ailus,
Tomi Valkeinen, Laurent Pinchart, linux-media, linux-renesas-soc,
linux-kernel
Cc: Niklas Söderlund, Laurent Pinchart
Each AFE lane has a set of control and offset registers. The registers
themself are undocumented but later datasheets program more of them with
magic values. Before exploding the driver with more defines to name them
all rework the AFE ones to be able to address all controls and offsets.
Also move a stray define that is out of sequence.
There is no functional change.
Signed-off-by: Niklas Söderlund <niklas.soderlund+renesas@ragnatech.se>
Tested-by: Tomi Valkeinen <tomi.valkeinen+renesas@ideasonboard.com>
Reviewed-by: Laurent Pinchart <laurent.pinchart+renesas@ideasonboard.com>
---
* Changes since v2
- Improve spelling in commit message.
* Changes since v1
- Adjust line length.
---
drivers/media/platform/renesas/rcar-csi2.c | 32 +++++++++++-----------
1 file changed, 16 insertions(+), 16 deletions(-)
diff --git a/drivers/media/platform/renesas/rcar-csi2.c b/drivers/media/platform/renesas/rcar-csi2.c
index 358e7470befc..cdd358b4a973 100644
--- a/drivers/media/platform/renesas/rcar-csi2.c
+++ b/drivers/media/platform/renesas/rcar-csi2.c
@@ -177,15 +177,14 @@ struct rcar_csi2;
#define V4H_PPI_RW_OFFSETCAL_CFG_0_REG 0x21ca0
/* V4H CORE registers */
-#define V4H_CORE_DIG_IOCTRL_RW_AFE_LANE0_CTRL_2_REG(n) (0x22040 + ((n) * 2)) /* n = 0 - 15 */
-#define V4H_CORE_DIG_IOCTRL_RW_AFE_LANE1_CTRL_2_REG(n) (0x22440 + ((n) * 2)) /* n = 0 - 15 */
-#define V4H_CORE_DIG_IOCTRL_RW_AFE_LANE2_CTRL_2_REG(n) (0x22840 + ((n) * 2)) /* n = 0 - 15 */
-#define V4H_CORE_DIG_IOCTRL_RW_AFE_LANE3_CTRL_2_REG(n) (0x22c40 + ((n) * 2)) /* n = 0 - 15 */
-#define V4H_CORE_DIG_IOCTRL_RW_AFE_LANE4_CTRL_2_REG(n) (0x23040 + ((n) * 2)) /* n = 0 - 15 */
+
+#define V4H_CORE_DIG_IOCTRL_RW_AFE_LANEl_CTRL_2_REG(l, n) (0x22040 + ((l) * 0x400) + ((n) * 2))
+#define V4H_CORE_DIG_IOCTRL_RW_AFE_LANEl_CTRL_3_REG(l, n) (0x22060 + ((l) * 0x400) + ((n) * 2))
+#define V4H_CORE_DIG_IOCTRL_RW_AFE_LANEl_CTRL_4_REG(l, n) (0x22080 + ((l) * 0x400) + ((n) * 2))
+
#define V4H_CORE_DIG_IOCTRL_RW_AFE_CB_CTRL_2_REG(n) (0x23840 + ((n) * 2)) /* n = 0 - 11 */
#define V4H_CORE_DIG_RW_COMMON_REG(n) (0x23880 + ((n) * 2)) /* n = 0 - 15 */
#define V4H_CORE_DIG_ANACTRL_RW_COMMON_ANACTRL_REG(n) (0x239e0 + ((n) * 2)) /* n = 0 - 3 */
-#define V4H_CORE_DIG_CLANE_1_RW_HS_TX_6_REG 0x2a60c
/* V4H C-PHY */
#define V4H_CORE_DIG_RW_TRIO0_REG(n) (0x22100 + ((n) * 2)) /* n = 0 - 3 */
@@ -197,6 +196,7 @@ struct rcar_csi2;
#define V4H_CORE_DIG_CLANE_1_RW_CFG_0_REG 0x2a400
#define V4H_CORE_DIG_CLANE_1_RW_LP_0_REG 0x2a480
#define V4H_CORE_DIG_CLANE_1_RW_HS_RX_REG(n) (0x2a500 + ((n) * 2)) /* n = 0 - 6 */
+#define V4H_CORE_DIG_CLANE_1_RW_HS_TX_6_REG 0x2a60c
#define V4H_CORE_DIG_CLANE_2_RW_CFG_0_REG 0x2a800
#define V4H_CORE_DIG_CLANE_2_RW_LP_0_REG 0x2a880
#define V4H_CORE_DIG_CLANE_2_RW_HS_RX_REG(n) (0x2a900 + ((n) * 2)) /* n = 0 - 6 */
@@ -1246,11 +1246,11 @@ static int rcsi2_c_phy_setting_v4h(struct rcar_csi2 *priv, int mbps)
rcsi2_write16(priv, V4H_CORE_DIG_CLANE_1_RW_HS_RX_REG(2), conf->rx2);
rcsi2_write16(priv, V4H_CORE_DIG_CLANE_2_RW_HS_RX_REG(2), conf->rx2);
- rcsi2_write16(priv, V4H_CORE_DIG_IOCTRL_RW_AFE_LANE0_CTRL_2_REG(2), 0x0001);
- rcsi2_write16(priv, V4H_CORE_DIG_IOCTRL_RW_AFE_LANE1_CTRL_2_REG(2), 0);
- rcsi2_write16(priv, V4H_CORE_DIG_IOCTRL_RW_AFE_LANE2_CTRL_2_REG(2), 0x0001);
- rcsi2_write16(priv, V4H_CORE_DIG_IOCTRL_RW_AFE_LANE3_CTRL_2_REG(2), 0x0001);
- rcsi2_write16(priv, V4H_CORE_DIG_IOCTRL_RW_AFE_LANE4_CTRL_2_REG(2), 0);
+ rcsi2_write16(priv, V4H_CORE_DIG_IOCTRL_RW_AFE_LANEl_CTRL_2_REG(0, 2), 0x0001);
+ rcsi2_write16(priv, V4H_CORE_DIG_IOCTRL_RW_AFE_LANEl_CTRL_2_REG(1, 2), 0);
+ rcsi2_write16(priv, V4H_CORE_DIG_IOCTRL_RW_AFE_LANEl_CTRL_2_REG(2, 2), 0x0001);
+ rcsi2_write16(priv, V4H_CORE_DIG_IOCTRL_RW_AFE_LANEl_CTRL_2_REG(3, 2), 0x0001);
+ rcsi2_write16(priv, V4H_CORE_DIG_IOCTRL_RW_AFE_LANEl_CTRL_2_REG(4, 2), 0);
rcsi2_write16(priv, V4H_CORE_DIG_RW_TRIO0_REG(0), conf->trio0);
rcsi2_write16(priv, V4H_CORE_DIG_RW_TRIO1_REG(0), conf->trio0);
@@ -1267,13 +1267,13 @@ static int rcsi2_c_phy_setting_v4h(struct rcar_csi2 *priv, int mbps)
/* Configure data line order. */
rsci2_set_line_order(priv, priv->line_orders[0],
V4H_CORE_DIG_CLANE_0_RW_CFG_0_REG,
- V4H_CORE_DIG_IOCTRL_RW_AFE_LANE0_CTRL_2_REG(9));
+ V4H_CORE_DIG_IOCTRL_RW_AFE_LANEl_CTRL_2_REG(0, 9));
rsci2_set_line_order(priv, priv->line_orders[1],
V4H_CORE_DIG_CLANE_1_RW_CFG_0_REG,
- V4H_CORE_DIG_IOCTRL_RW_AFE_LANE1_CTRL_2_REG(9));
+ V4H_CORE_DIG_IOCTRL_RW_AFE_LANEl_CTRL_2_REG(1, 9));
rsci2_set_line_order(priv, priv->line_orders[2],
V4H_CORE_DIG_CLANE_2_RW_CFG_0_REG,
- V4H_CORE_DIG_IOCTRL_RW_AFE_LANE2_CTRL_2_REG(9));
+ V4H_CORE_DIG_IOCTRL_RW_AFE_LANEl_CTRL_2_REG(2, 9));
/* TODO: This registers is not documented. */
rcsi2_write16(priv, V4H_CORE_DIG_CLANE_1_RW_HS_TX_6_REG, 0x5000);
@@ -1289,8 +1289,8 @@ static int rcsi2_c_phy_setting_v4h(struct rcar_csi2 *priv, int mbps)
}
/* C-PHY setting - analog programing*/
- rcsi2_write16(priv, V4H_CORE_DIG_IOCTRL_RW_AFE_LANE0_CTRL_2_REG(9), conf->lane29);
- rcsi2_write16(priv, V4H_CORE_DIG_IOCTRL_RW_AFE_LANE0_CTRL_2_REG(7), conf->lane27);
+ rcsi2_write16(priv, V4H_CORE_DIG_IOCTRL_RW_AFE_LANEl_CTRL_2_REG(0, 9), conf->lane29);
+ rcsi2_write16(priv, V4H_CORE_DIG_IOCTRL_RW_AFE_LANEl_CTRL_2_REG(0, 7), conf->lane27);
return 0;
}
--
2.49.0
^ permalink raw reply related [flat|nested] 6+ messages in thread
* [PATCH v4 3/4] media: rcar-csi2: Update start procedure for V4H
2025-06-12 17:59 [PATCH v4 0/4] media: rcar-csi2: Add D-PHY support for V4H Niklas Söderlund
2025-06-12 17:59 ` [PATCH v4 1/4] media: rcar-csi2: Clarify usage of mbps and msps Niklas Söderlund
2025-06-12 17:59 ` [PATCH v4 2/4] media: rcar-csi2: Rework macros to access AFE lanes Niklas Söderlund
@ 2025-06-12 17:59 ` Niklas Söderlund
2025-06-12 17:59 ` [PATCH v4 4/4] media: rcar-csi2: Add D-PHY support " Niklas Söderlund
3 siblings, 0 replies; 6+ messages in thread
From: Niklas Söderlund @ 2025-06-12 17:59 UTC (permalink / raw)
To: Mauro Carvalho Chehab, Geert Uytterhoeven, Sakari Ailus,
Tomi Valkeinen, Laurent Pinchart, linux-media, linux-renesas-soc,
linux-kernel
Cc: Niklas Söderlund, Laurent Pinchart
Prepare for adding D-PHY support to the driver by first updating the
generic startup procedure that covers both C-PHY and D-PHY operations.
The starting procedure where updated in later versions of the datasheet.
Most of the configuration is only documented as tables of magic values
in the documentation. Each step is however marked with a T<n> marker,
inject these markers in the comments to make it easier to map driver to
documentation.
Signed-off-by: Niklas Söderlund <niklas.soderlund+renesas@ragnatech.se>
Tested-by: Tomi Valkeinen <tomi.valkeinen+renesas@ideasonboard.com>
Reviewed-by: Laurent Pinchart <laurent.pinchart+renesas@ideasonboard.com>
---
drivers/media/platform/renesas/rcar-csi2.c | 84 +++++++++++++++-------
1 file changed, 58 insertions(+), 26 deletions(-)
diff --git a/drivers/media/platform/renesas/rcar-csi2.c b/drivers/media/platform/renesas/rcar-csi2.c
index cdd358b4a973..7ba637d8683b 100644
--- a/drivers/media/platform/renesas/rcar-csi2.c
+++ b/drivers/media/platform/renesas/rcar-csi2.c
@@ -1199,7 +1199,8 @@ static int rcsi2_wait_phy_start_v4h(struct rcar_csi2 *priv, u32 match)
return -ETIMEDOUT;
}
-static int rcsi2_c_phy_setting_v4h(struct rcar_csi2 *priv, int mbps)
+static const struct rcsi2_cphy_setting *
+rcsi2_c_phy_setting_v4h(struct rcar_csi2 *priv, int mbps)
{
const struct rcsi2_cphy_setting *conf;
int msps;
@@ -1214,7 +1215,7 @@ static int rcsi2_c_phy_setting_v4h(struct rcar_csi2 *priv, int mbps)
if (!conf->msps) {
dev_err(priv->dev, "Unsupported PHY speed for msps setting (%u Msps)", msps);
- return -ERANGE;
+ return NULL;
}
/* C-PHY specific */
@@ -1278,27 +1279,14 @@ static int rcsi2_c_phy_setting_v4h(struct rcar_csi2 *priv, int mbps)
/* TODO: This registers is not documented. */
rcsi2_write16(priv, V4H_CORE_DIG_CLANE_1_RW_HS_TX_6_REG, 0x5000);
- /* Leave Shutdown mode */
- rcsi2_write(priv, V4H_DPHY_RSTZ_REG, BIT(0));
- rcsi2_write(priv, V4H_PHY_SHUTDOWNZ_REG, BIT(0));
-
- /* Wait for calibration */
- if (rcsi2_wait_phy_start_v4h(priv, V4H_ST_PHYST_ST_PHY_READY)) {
- dev_err(priv->dev, "PHY calibration failed\n");
- return -ETIMEDOUT;
- }
-
- /* C-PHY setting - analog programing*/
- rcsi2_write16(priv, V4H_CORE_DIG_IOCTRL_RW_AFE_LANEl_CTRL_2_REG(0, 9), conf->lane29);
- rcsi2_write16(priv, V4H_CORE_DIG_IOCTRL_RW_AFE_LANEl_CTRL_2_REG(0, 7), conf->lane27);
-
- return 0;
+ return conf;
}
static int rcsi2_start_receiver_v4h(struct rcar_csi2 *priv,
struct v4l2_subdev_state *state)
{
const struct rcar_csi2_format *format;
+ const struct rcsi2_cphy_setting *cphy;
const struct v4l2_mbus_framefmt *fmt;
unsigned int lanes;
int mbps;
@@ -1318,24 +1306,35 @@ static int rcsi2_start_receiver_v4h(struct rcar_csi2 *priv,
if (mbps < 0)
return mbps;
- /* Reset LINK and PHY*/
+ /* T0: Reset LINK and PHY*/
rcsi2_write(priv, V4H_CSI2_RESETN_REG, 0);
rcsi2_write(priv, V4H_DPHY_RSTZ_REG, 0);
rcsi2_write(priv, V4H_PHY_SHUTDOWNZ_REG, 0);
- /* PHY static setting */
- rcsi2_write(priv, V4H_PHY_EN_REG, V4H_PHY_EN_ENABLE_CLK);
+ /* T1: PHY static setting */
+ rcsi2_write(priv, V4H_PHY_EN_REG, V4H_PHY_EN_ENABLE_CLK |
+ V4H_PHY_EN_ENABLE_0 | V4H_PHY_EN_ENABLE_1 |
+ V4H_PHY_EN_ENABLE_2 | V4H_PHY_EN_ENABLE_3);
rcsi2_write(priv, V4H_FLDC_REG, 0);
rcsi2_write(priv, V4H_FLDD_REG, 0);
rcsi2_write(priv, V4H_IDIC_REG, 0);
rcsi2_write(priv, V4H_PHY_MODE_REG, V4H_PHY_MODE_CPHY);
rcsi2_write(priv, V4H_N_LANES_REG, lanes - 1);
- /* Reset CSI2 */
+ rcsi2_write(priv, V4M_FRXM_REG,
+ V4M_FRXM_FORCERXMODE_0 | V4M_FRXM_FORCERXMODE_1 |
+ V4M_FRXM_FORCERXMODE_2 | V4M_FRXM_FORCERXMODE_3);
+ rcsi2_write(priv, V4M_OVR1_REG,
+ V4M_OVR1_FORCERXMODE_0 | V4M_OVR1_FORCERXMODE_1 |
+ V4M_OVR1_FORCERXMODE_2 | V4M_OVR1_FORCERXMODE_3);
+
+ /* T2: Reset CSI2 */
rcsi2_write(priv, V4H_CSI2_RESETN_REG, BIT(0));
/* Registers static setting through APB */
/* Common setting */
+ rcsi2_write16(priv, V4H_PPI_STARTUP_RW_COMMON_DPHY_REG(10), 0x0030);
+ rcsi2_write16(priv, V4H_CORE_DIG_ANACTRL_RW_COMMON_ANACTRL_REG(2), 0x1444);
rcsi2_write16(priv, V4H_CORE_DIG_ANACTRL_RW_COMMON_ANACTRL_REG(0), 0x1bfd);
rcsi2_write16(priv, V4H_PPI_STARTUP_RW_COMMON_STARTUP_1_1_REG, 0x0233);
rcsi2_write16(priv, V4H_PPI_STARTUP_RW_COMMON_DPHY_REG(6), 0x0027);
@@ -1350,15 +1349,48 @@ static int rcsi2_start_receiver_v4h(struct rcar_csi2 *priv,
rcsi2_write16(priv, V4H_PPI_RW_LPDCOCAL_COARSE_CFG_REG, 0x0105);
rcsi2_write16(priv, V4H_CORE_DIG_IOCTRL_RW_AFE_CB_CTRL_2_REG(6), 0x1000);
rcsi2_write16(priv, V4H_PPI_RW_COMMON_CFG_REG, 0x0003);
+ rcsi2_write16(priv, V4H_CORE_DIG_IOCTRL_RW_AFE_CB_CTRL_2_REG(0), 0x0000);
+ rcsi2_write16(priv, V4H_CORE_DIG_IOCTRL_RW_AFE_CB_CTRL_2_REG(1), 0x0400);
+ rcsi2_write16(priv, V4H_CORE_DIG_IOCTRL_RW_AFE_CB_CTRL_2_REG(3), 0x41f6);
+ rcsi2_write16(priv, V4H_CORE_DIG_IOCTRL_RW_AFE_CB_CTRL_2_REG(0), 0x0000);
+ rcsi2_write16(priv, V4H_CORE_DIG_IOCTRL_RW_AFE_CB_CTRL_2_REG(3), 0x43f6);
+ rcsi2_write16(priv, V4H_CORE_DIG_IOCTRL_RW_AFE_CB_CTRL_2_REG(6), 0x3000);
+ rcsi2_write16(priv, V4H_CORE_DIG_IOCTRL_RW_AFE_CB_CTRL_2_REG(7), 0x0000);
+ rcsi2_write16(priv, V4H_CORE_DIG_IOCTRL_RW_AFE_CB_CTRL_2_REG(6), 0x7000);
+ rcsi2_write16(priv, V4H_CORE_DIG_IOCTRL_RW_AFE_CB_CTRL_2_REG(7), 0x0000);
+ rcsi2_write16(priv, V4H_CORE_DIG_IOCTRL_RW_AFE_CB_CTRL_2_REG(5), 0x4000);
- /* C-PHY settings */
- ret = rcsi2_c_phy_setting_v4h(priv, mbps);
- if (ret)
- return ret;
+ /* T3: PHY settings */
+ cphy = rcsi2_c_phy_setting_v4h(priv, mbps);
+ if (!cphy)
+ return -ERANGE;
+ /* T4: Leave Shutdown mode */
+ rcsi2_write(priv, V4H_DPHY_RSTZ_REG, BIT(0));
+ rcsi2_write(priv, V4H_PHY_SHUTDOWNZ_REG, BIT(0));
+
+ /* T5: Wait for calibration */
+ if (rcsi2_wait_phy_start_v4h(priv, V4H_ST_PHYST_ST_PHY_READY)) {
+ dev_err(priv->dev, "PHY calibration failed\n");
+ return -ETIMEDOUT;
+ }
+
+ /* T6: Analog programming */
+ for (unsigned int l = 0; l < 3; l++) {
+ rcsi2_write16(priv, V4H_CORE_DIG_IOCTRL_RW_AFE_LANEl_CTRL_2_REG(l, 9),
+ cphy->lane29);
+ rcsi2_write16(priv, V4H_CORE_DIG_IOCTRL_RW_AFE_LANEl_CTRL_2_REG(l, 7),
+ cphy->lane27);
+ }
+
+ /* T7: Wait for stop state */
rcsi2_wait_phy_start_v4h(priv, V4H_ST_PHYST_ST_STOPSTATE_0 |
V4H_ST_PHYST_ST_STOPSTATE_1 |
- V4H_ST_PHYST_ST_STOPSTATE_2);
+ V4H_ST_PHYST_ST_STOPSTATE_2 |
+ V4H_ST_PHYST_ST_STOPSTATE_3);
+
+ /* T8: De-assert FRXM */
+ rcsi2_write(priv, V4M_FRXM_REG, 0);
return 0;
}
--
2.49.0
^ permalink raw reply related [flat|nested] 6+ messages in thread
* [PATCH v4 4/4] media: rcar-csi2: Add D-PHY support for V4H
2025-06-12 17:59 [PATCH v4 0/4] media: rcar-csi2: Add D-PHY support for V4H Niklas Söderlund
` (2 preceding siblings ...)
2025-06-12 17:59 ` [PATCH v4 3/4] media: rcar-csi2: Update start procedure for V4H Niklas Söderlund
@ 2025-06-12 17:59 ` Niklas Söderlund
2025-06-12 22:21 ` Laurent Pinchart
3 siblings, 1 reply; 6+ messages in thread
From: Niklas Söderlund @ 2025-06-12 17:59 UTC (permalink / raw)
To: Mauro Carvalho Chehab, Geert Uytterhoeven, Sakari Ailus,
Tomi Valkeinen, Laurent Pinchart, linux-media, linux-renesas-soc,
linux-kernel
Cc: Niklas Söderlund
Add D-PHY support for V4H in addition to the already supported C-PHY.
The common start-up procedure for C-PHY and D-PHY is shared, only PHY
setup differ. Extend the V4H setup with D-PHY support as documented in
the datasheet (Rev.1.21).
Most of the start-up procedure is only documented as magic values in
tables, there is little documentation to make the settings more clear.
Wherever possible formulas or lookup tables are used as they are
documented in the datasheet.
Signed-off-by: Niklas Söderlund <niklas.soderlund+renesas@ragnatech.se>
Tested-by: Tomi Valkeinen <tomi.valkeinen+renesas@ideasonboard.com>
---
* Fixes since v3
- Improve spelling in commit message and fix a comment style issue.
- Use DIV_ROUND_UP() instead of roundup().
- Correct bad mbps comparison in rcsi2_d_phy_setting_v4h_lut_lookup().
- Use ilog2() instead of a stacked if .. else if .. else if .. else ..
construct.
* Fixes since v2
- Stire DESKEW settings in an array and loop over it instead of opene
coding it.
* Fixes since v1
- Init cphy variables to not trigger false -Wmaybe-uninitialized
warning.
- Adjust line lengths.
---
drivers/media/platform/renesas/rcar-csi2.c | 230 ++++++++++++++++++++-
1 file changed, 220 insertions(+), 10 deletions(-)
diff --git a/drivers/media/platform/renesas/rcar-csi2.c b/drivers/media/platform/renesas/rcar-csi2.c
index 7ba637d8683b..0350eb76df36 100644
--- a/drivers/media/platform/renesas/rcar-csi2.c
+++ b/drivers/media/platform/renesas/rcar-csi2.c
@@ -172,6 +172,7 @@ struct rcar_csi2;
#define V4H_PPI_RW_LPDCOCAL_TWAIT_CONFIG_REG 0x21c0a
#define V4H_PPI_RW_LPDCOCAL_VT_CONFIG_REG 0x21c0c
#define V4H_PPI_RW_LPDCOCAL_COARSE_CFG_REG 0x21c10
+#define V4H_PPI_RW_DDLCAL_CFG_n_REG(n) (0x21c40 + ((n) * 2)) /* n = 0 - 7 */
#define V4H_PPI_RW_COMMON_CFG_REG 0x21c6c
#define V4H_PPI_RW_TERMCAL_CFG_0_REG 0x21c80
#define V4H_PPI_RW_OFFSETCAL_CFG_0_REG 0x21ca0
@@ -185,6 +186,13 @@ struct rcar_csi2;
#define V4H_CORE_DIG_IOCTRL_RW_AFE_CB_CTRL_2_REG(n) (0x23840 + ((n) * 2)) /* n = 0 - 11 */
#define V4H_CORE_DIG_RW_COMMON_REG(n) (0x23880 + ((n) * 2)) /* n = 0 - 15 */
#define V4H_CORE_DIG_ANACTRL_RW_COMMON_ANACTRL_REG(n) (0x239e0 + ((n) * 2)) /* n = 0 - 3 */
+#define V4H_CORE_DIG_COMMON_RW_DESKEW_FINE_MEM_REG 0x23fe0
+
+#define V4H_CORE_DIG_DLANE_l_RW_CFG_n_REG(l, n) (0x26000 + ((l) * 0x400) + ((n) * 2))
+#define V4H_CORE_DIG_DLANE_l_RW_LP_n_REG(l, n) (0x26080 + ((l) * 0x400) + ((n) * 2))
+#define V4H_CORE_DIG_DLANE_l_RW_HS_RX_n_REG(l, n) (0x26100 + ((l) * 0x400) + ((n) * 2))
+#define V4H_CORE_DIG_DLANE_CLK_RW_LP_n_REG(n) V4H_CORE_DIG_DLANE_l_RW_LP_n_REG(4, (n))
+#define V4H_CORE_DIG_DLANE_CLK_RW_HS_RX_n_REG(n) V4H_CORE_DIG_DLANE_l_RW_HS_RX_n_REG(4, (n))
/* V4H C-PHY */
#define V4H_CORE_DIG_RW_TRIO0_REG(n) (0x22100 + ((n) * 2)) /* n = 0 - 3 */
@@ -1282,11 +1290,193 @@ rcsi2_c_phy_setting_v4h(struct rcar_csi2 *priv, int mbps)
return conf;
}
+struct rcsi2_d_phy_setting_v4h_lut_value {
+ unsigned int mbps;
+ unsigned char cfg_1;
+ unsigned char cfg_5_94;
+ unsigned char cfg_5_30;
+ unsigned char lane_ctrl_2_8;
+ unsigned char rw_hs_rx_3_83;
+ unsigned char rw_hs_rx_3_20;
+ unsigned char rw_hs_rx_6;
+ unsigned char rw_hs_rx_1;
+};
+
+static const struct rcsi2_d_phy_setting_v4h_lut_value *
+rcsi2_d_phy_setting_v4h_lut_lookup(int mbps)
+{
+ static const struct rcsi2_d_phy_setting_v4h_lut_value values[] = {
+ { 4500, 0x3f, 0x07, 0x00, 0x01, 0x02, 0x01, 0x0d, 0x10 },
+ { 4000, 0x47, 0x08, 0x01, 0x01, 0x05, 0x01, 0x0f, 0x0d },
+ { 3600, 0x4f, 0x09, 0x01, 0x01, 0x06, 0x01, 0x10, 0x0b },
+ { 3230, 0x57, 0x0a, 0x01, 0x01, 0x06, 0x01, 0x12, 0x09 },
+ { 3000, 0x47, 0x08, 0x00, 0x00, 0x03, 0x01, 0x0f, 0x0c },
+ { 2700, 0x4f, 0x09, 0x01, 0x00, 0x06, 0x01, 0x10, 0x0b },
+ { 2455, 0x57, 0x0a, 0x01, 0x00, 0x06, 0x01, 0x12, 0x09 },
+ { 2250, 0x5f, 0x0b, 0x01, 0x00, 0x08, 0x01, 0x13, 0x08 },
+ { 2077, 0x67, 0x0c, 0x01, 0x00, 0x06, 0x02, 0x15, 0x0d },
+ { 1929, 0x6f, 0x0d, 0x02, 0x00, 0x06, 0x02, 0x17, 0x0d },
+ { 1800, 0x77, 0x0e, 0x02, 0x00, 0x06, 0x02, 0x18, 0x0d },
+ { 1688, 0x7f, 0x0f, 0x02, 0x00, 0x08, 0x02, 0x1a, 0x0d },
+ { 1588, 0x87, 0x10, 0x02, 0x00, 0x08, 0x02, 0x1b, 0x0d },
+ { 1500, 0x8f, 0x11, 0x03, 0x00, 0x08, 0x02, 0x1d, 0x0c },
+ };
+
+ for (unsigned int i = 0; i < ARRAY_SIZE(values); i++)
+ if (mbps >= values[i].mbps)
+ return &values[i];
+
+ return NULL;
+}
+
+static int rcsi2_d_phy_setting_v4h(struct rcar_csi2 *priv, int mbps)
+{
+ const struct rcsi2_d_phy_setting_v4h_lut_value *lut =
+ rcsi2_d_phy_setting_v4h_lut_lookup(mbps);
+ u16 val;
+
+ rcsi2_write16(priv, V4H_CORE_DIG_RW_COMMON_REG(7), 0x0000);
+ rcsi2_write16(priv, V4H_PPI_STARTUP_RW_COMMON_DPHY_REG(7), mbps > 1500 ? 0x0028 : 0x0068);
+ rcsi2_write16(priv, V4H_PPI_STARTUP_RW_COMMON_DPHY_REG(8), 0x0050);
+ rcsi2_write16(priv, V4H_PPI_RW_DDLCAL_CFG_n_REG(0), 0x0063);
+ rcsi2_write16(priv, V4H_PPI_RW_DDLCAL_CFG_n_REG(7), 0x1132);
+ rcsi2_write16(priv, V4H_PPI_RW_DDLCAL_CFG_n_REG(1), 0x1340);
+ rcsi2_write16(priv, V4H_PPI_RW_DDLCAL_CFG_n_REG(2), 0x4b13);
+ rcsi2_write16(priv, V4H_PPI_RW_DDLCAL_CFG_n_REG(4), 0x000a);
+ rcsi2_write16(priv, V4H_PPI_RW_DDLCAL_CFG_n_REG(6), 0x800a);
+ rcsi2_write16(priv, V4H_PPI_RW_DDLCAL_CFG_n_REG(7), 0x1109);
+
+ if (mbps > 1500) {
+ val = DIV_ROUND_UP(5 * mbps, 64);
+ rcsi2_write16(priv, V4H_PPI_RW_DDLCAL_CFG_n_REG(3), val);
+ }
+
+ if (lut) {
+ rcsi2_modify16(priv, V4H_PPI_RW_DDLCAL_CFG_n_REG(1),
+ lut->cfg_1, 0x00ff);
+ rcsi2_modify16(priv, V4H_PPI_RW_DDLCAL_CFG_n_REG(5),
+ lut->cfg_5_94 << 4, 0x03f0);
+ rcsi2_modify16(priv, V4H_PPI_RW_DDLCAL_CFG_n_REG(5),
+ lut->cfg_5_30 << 0, 0x000f);
+
+ for (unsigned int l = 0; l < 5; l++)
+ rcsi2_modify16(priv, V4H_CORE_DIG_IOCTRL_RW_AFE_LANEl_CTRL_2_REG(l, 8),
+ lut->lane_ctrl_2_8 << 12, 0x1000);
+ }
+
+ for (unsigned int l = 0; l < 4; l++)
+ rcsi2_write16(priv, V4H_CORE_DIG_DLANE_l_RW_LP_n_REG(l, 0), 0x463c);
+
+ rcsi2_write16(priv, V4H_CORE_DIG_IOCTRL_RW_AFE_LANEl_CTRL_2_REG(0, 2), 0x0000);
+ rcsi2_write16(priv, V4H_CORE_DIG_IOCTRL_RW_AFE_LANEl_CTRL_2_REG(1, 2), 0x0000);
+ rcsi2_write16(priv, V4H_CORE_DIG_IOCTRL_RW_AFE_LANEl_CTRL_2_REG(2, 2), 0x0001);
+ rcsi2_write16(priv, V4H_CORE_DIG_IOCTRL_RW_AFE_LANEl_CTRL_2_REG(3, 2), 0x0000);
+ rcsi2_write16(priv, V4H_CORE_DIG_IOCTRL_RW_AFE_LANEl_CTRL_2_REG(4, 2), 0x0000);
+
+ rcsi2_write16(priv, V4H_CORE_DIG_RW_COMMON_REG(6), 0x0009);
+
+ val = mbps > 1500 ? 0x0800 : 0x0802;
+ for (unsigned int l = 0; l < 5; l++)
+ rcsi2_write16(priv, V4H_CORE_DIG_IOCTRL_RW_AFE_LANEl_CTRL_2_REG(l, 12), val);
+
+ val = mbps > 1500 ? 0x0000 : 0x0002;
+ for (unsigned int l = 0; l < 5; l++)
+ rcsi2_write16(priv, V4H_CORE_DIG_IOCTRL_RW_AFE_LANEl_CTRL_2_REG(l, 13), val);
+
+ if (mbps >= 80) {
+ /* 2560: 6, 1280: 5, 640: 4, 320: 3, 160: 2, 80: 1 */
+ val = ilog2(mbps / 80) + 1;
+ rcsi2_modify16(priv,
+ V4H_CORE_DIG_IOCTRL_RW_AFE_LANEl_CTRL_2_REG(2, 9),
+ val << 5, 0xe0);
+ }
+
+ rcsi2_write16(priv, V4H_CORE_DIG_DLANE_CLK_RW_HS_RX_n_REG(0), 0x091c);
+ rcsi2_write16(priv, V4H_CORE_DIG_DLANE_CLK_RW_HS_RX_n_REG(7), 0x3b06);
+
+ val = DIV_ROUND_UP(1200, mbps) + 12;
+ for (unsigned int l = 0; l < 4; l++)
+ rcsi2_modify16(priv, V4H_CORE_DIG_DLANE_l_RW_HS_RX_n_REG(l, 0), val << 8, 0xf0);
+
+ val = mbps > 1500 ? 0x0004 : 0x0008;
+ for (unsigned int l = 0; l < 4; l++)
+ rcsi2_write16(priv, V4H_CORE_DIG_DLANE_l_RW_CFG_n_REG(l, 1), val);
+
+ val = mbps > 2500 ? 0x669a : mbps > 1500 ? 0xe69a : 0xe69b;
+ for (unsigned int l = 0; l < 4; l++)
+ rcsi2_write16(priv, V4H_CORE_DIG_DLANE_l_RW_HS_RX_n_REG(l, 2), val);
+
+ for (unsigned int l = 0; l < 4; l++)
+ rcsi2_write16(priv, V4H_CORE_DIG_DLANE_l_RW_LP_n_REG(l, 0), 0x163c);
+ rcsi2_write16(priv, V4H_CORE_DIG_DLANE_CLK_RW_LP_n_REG(0), 0x163c);
+
+ if (lut) {
+ for (unsigned int l = 0; l < 4; l++)
+ rcsi2_modify16(priv, V4H_CORE_DIG_DLANE_l_RW_HS_RX_n_REG(l, 1),
+ lut->rw_hs_rx_1, 0xff);
+ }
+
+ for (unsigned int l = 0; l < 4; l++)
+ rcsi2_write16(priv, V4H_CORE_DIG_DLANE_l_RW_HS_RX_n_REG(l, 3), 0x9209);
+
+ for (unsigned int l = 0; l < 4; l++)
+ rcsi2_write16(priv, V4H_CORE_DIG_DLANE_l_RW_HS_RX_n_REG(l, 4), 0x0096);
+
+ for (unsigned int l = 0; l < 4; l++)
+ rcsi2_write16(priv, V4H_CORE_DIG_DLANE_l_RW_HS_RX_n_REG(l, 5), 0x0100);
+
+ for (unsigned int l = 0; l < 4; l++)
+ rcsi2_write16(priv, V4H_CORE_DIG_DLANE_l_RW_HS_RX_n_REG(l, 6), 0x2d02);
+
+ for (unsigned int l = 0; l < 4; l++)
+ rcsi2_write16(priv, V4H_CORE_DIG_DLANE_l_RW_HS_RX_n_REG(l, 7), 0x1b06);
+
+ if (lut) {
+ /*
+ * Documentation LUT have two values but document writing both
+ * values in a single write.
+ */
+ for (unsigned int l = 0; l < 4; l++)
+ rcsi2_modify16(priv, V4H_CORE_DIG_DLANE_l_RW_HS_RX_n_REG(l, 3),
+ lut->rw_hs_rx_3_83 << 3 | lut->rw_hs_rx_3_20, 0x1ff);
+
+ for (unsigned int l = 0; l < 4; l++)
+ rcsi2_modify16(priv, V4H_CORE_DIG_DLANE_l_RW_HS_RX_n_REG(l, 6),
+ lut->rw_hs_rx_6 << 8, 0xff00);
+ }
+
+ static const u16 deskew_fine[] = {
+ 0x0404, 0x040c, 0x0414, 0x041c, 0x0423, 0x0429, 0x0430, 0x043a,
+ 0x0445, 0x044a, 0x0450, 0x045a, 0x0465, 0x0469, 0x0472, 0x047a,
+ 0x0485, 0x0489, 0x0490, 0x049a, 0x04a4, 0x04ac, 0x04b4, 0x04bc,
+ 0x04c4, 0x04cc, 0x04d4, 0x04dc, 0x04e4, 0x04ec, 0x04f4, 0x04fc,
+ 0x0504, 0x050c, 0x0514, 0x051c, 0x0523, 0x0529, 0x0530, 0x053a,
+ 0x0545, 0x054a, 0x0550, 0x055a, 0x0565, 0x0569, 0x0572, 0x057a,
+ 0x0585, 0x0589, 0x0590, 0x059a, 0x05a4, 0x05ac, 0x05b4, 0x05bc,
+ 0x05c4, 0x05cc, 0x05d4, 0x05dc, 0x05e4, 0x05ec, 0x05f4, 0x05fc,
+ 0x0604, 0x060c, 0x0614, 0x061c, 0x0623, 0x0629, 0x0632, 0x063a,
+ 0x0645, 0x064a, 0x0650, 0x065a, 0x0665, 0x0669, 0x0672, 0x067a,
+ 0x0685, 0x0689, 0x0690, 0x069a, 0x06a4, 0x06ac, 0x06b4, 0x06bc,
+ 0x06c4, 0x06cc, 0x06d4, 0x06dc, 0x06e4, 0x06ec, 0x06f4, 0x06fc,
+ 0x0704, 0x070c, 0x0714, 0x071c, 0x0723, 0x072a, 0x0730, 0x073a,
+ 0x0745, 0x074a, 0x0750, 0x075a, 0x0765, 0x0769, 0x0772, 0x077a,
+ 0x0785, 0x0789, 0x0790, 0x079a, 0x07a4, 0x07ac, 0x07b4, 0x07bc,
+ 0x07c4, 0x07cc, 0x07d4, 0x07dc, 0x07e4, 0x07ec, 0x07f4, 0x07fc,
+ };
+
+ for (unsigned int i = 0; i < ARRAY_SIZE(deskew_fine); i++) {
+ rcsi2_write16(priv, V4H_CORE_DIG_COMMON_RW_DESKEW_FINE_MEM_REG,
+ deskew_fine[i]);
+ }
+
+ return 0;
+}
+
static int rcsi2_start_receiver_v4h(struct rcar_csi2 *priv,
struct v4l2_subdev_state *state)
{
+ const struct rcsi2_cphy_setting *cphy = NULL;
const struct rcar_csi2_format *format;
- const struct rcsi2_cphy_setting *cphy;
const struct v4l2_mbus_framefmt *fmt;
unsigned int lanes;
int mbps;
@@ -1318,7 +1508,8 @@ static int rcsi2_start_receiver_v4h(struct rcar_csi2 *priv,
rcsi2_write(priv, V4H_FLDC_REG, 0);
rcsi2_write(priv, V4H_FLDD_REG, 0);
rcsi2_write(priv, V4H_IDIC_REG, 0);
- rcsi2_write(priv, V4H_PHY_MODE_REG, V4H_PHY_MODE_CPHY);
+ rcsi2_write(priv, V4H_PHY_MODE_REG,
+ priv->cphy ? V4H_PHY_MODE_CPHY : V4H_PHY_MODE_DPHY);
rcsi2_write(priv, V4H_N_LANES_REG, lanes - 1);
rcsi2_write(priv, V4M_FRXM_REG,
@@ -1361,9 +1552,15 @@ static int rcsi2_start_receiver_v4h(struct rcar_csi2 *priv,
rcsi2_write16(priv, V4H_CORE_DIG_IOCTRL_RW_AFE_CB_CTRL_2_REG(5), 0x4000);
/* T3: PHY settings */
- cphy = rcsi2_c_phy_setting_v4h(priv, mbps);
- if (!cphy)
- return -ERANGE;
+ if (priv->cphy) {
+ cphy = rcsi2_c_phy_setting_v4h(priv, mbps);
+ if (!cphy)
+ return -ERANGE;
+ } else {
+ ret = rcsi2_d_phy_setting_v4h(priv, mbps);
+ if (ret)
+ return ret;
+ }
/* T4: Leave Shutdown mode */
rcsi2_write(priv, V4H_DPHY_RSTZ_REG, BIT(0));
@@ -1376,11 +1573,23 @@ static int rcsi2_start_receiver_v4h(struct rcar_csi2 *priv,
}
/* T6: Analog programming */
- for (unsigned int l = 0; l < 3; l++) {
- rcsi2_write16(priv, V4H_CORE_DIG_IOCTRL_RW_AFE_LANEl_CTRL_2_REG(l, 9),
- cphy->lane29);
- rcsi2_write16(priv, V4H_CORE_DIG_IOCTRL_RW_AFE_LANEl_CTRL_2_REG(l, 7),
- cphy->lane27);
+ if (priv->cphy) {
+ for (unsigned int l = 0; l < 3; l++) {
+ rcsi2_write16(priv, V4H_CORE_DIG_IOCTRL_RW_AFE_LANEl_CTRL_2_REG(l, 9),
+ cphy->lane29);
+ rcsi2_write16(priv, V4H_CORE_DIG_IOCTRL_RW_AFE_LANEl_CTRL_2_REG(l, 7),
+ cphy->lane27);
+ }
+ } else {
+ u16 val_2_9 = mbps > 2500 ? 0x14 : mbps > 1500 ? 0x04 : 0x00;
+ u16 val_2_15 = mbps > 1500 ? 0x03 : 0x00;
+
+ for (unsigned int l = 0; l < 5; l++) {
+ rcsi2_write16(priv, V4H_CORE_DIG_IOCTRL_RW_AFE_LANEl_CTRL_2_REG(l, 9),
+ val_2_9);
+ rcsi2_write16(priv, V4H_CORE_DIG_IOCTRL_RW_AFE_LANEl_CTRL_2_REG(l, 15),
+ val_2_15);
+ }
}
/* T7: Wait for stop state */
@@ -2245,6 +2454,7 @@ static const struct rcar_csi2_info rcar_csi2_info_r8a779g0 = {
.start_receiver = rcsi2_start_receiver_v4h,
.use_isp = true,
.support_cphy = true,
+ .support_dphy = true,
};
static const struct rcsi2_register_layout rcsi2_registers_v4m = {
--
2.49.0
^ permalink raw reply related [flat|nested] 6+ messages in thread
* Re: [PATCH v4 4/4] media: rcar-csi2: Add D-PHY support for V4H
2025-06-12 17:59 ` [PATCH v4 4/4] media: rcar-csi2: Add D-PHY support " Niklas Söderlund
@ 2025-06-12 22:21 ` Laurent Pinchart
0 siblings, 0 replies; 6+ messages in thread
From: Laurent Pinchart @ 2025-06-12 22:21 UTC (permalink / raw)
To: Niklas Söderlund
Cc: Mauro Carvalho Chehab, Geert Uytterhoeven, Sakari Ailus,
Tomi Valkeinen, linux-media, linux-renesas-soc, linux-kernel
Hi Niklas,
Thank you for the patch.
On Thu, Jun 12, 2025 at 07:59:04PM +0200, Niklas Söderlund wrote:
> Add D-PHY support for V4H in addition to the already supported C-PHY.
> The common start-up procedure for C-PHY and D-PHY is shared, only PHY
> setup differ. Extend the V4H setup with D-PHY support as documented in
> the datasheet (Rev.1.21).
>
> Most of the start-up procedure is only documented as magic values in
> tables, there is little documentation to make the settings more clear.
> Wherever possible formulas or lookup tables are used as they are
> documented in the datasheet.
>
> Signed-off-by: Niklas Söderlund <niklas.soderlund+renesas@ragnatech.se>
> Tested-by: Tomi Valkeinen <tomi.valkeinen+renesas@ideasonboard.com>
Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
> ---
> * Fixes since v3
> - Improve spelling in commit message and fix a comment style issue.
> - Use DIV_ROUND_UP() instead of roundup().
> - Correct bad mbps comparison in rcsi2_d_phy_setting_v4h_lut_lookup().
> - Use ilog2() instead of a stacked if .. else if .. else if .. else ..
> construct.
>
> * Fixes since v2
> - Stire DESKEW settings in an array and loop over it instead of opene
> coding it.
>
> * Fixes since v1
> - Init cphy variables to not trigger false -Wmaybe-uninitialized
> warning.
> - Adjust line lengths.
> ---
> drivers/media/platform/renesas/rcar-csi2.c | 230 ++++++++++++++++++++-
> 1 file changed, 220 insertions(+), 10 deletions(-)
>
> diff --git a/drivers/media/platform/renesas/rcar-csi2.c b/drivers/media/platform/renesas/rcar-csi2.c
> index 7ba637d8683b..0350eb76df36 100644
> --- a/drivers/media/platform/renesas/rcar-csi2.c
> +++ b/drivers/media/platform/renesas/rcar-csi2.c
> @@ -172,6 +172,7 @@ struct rcar_csi2;
> #define V4H_PPI_RW_LPDCOCAL_TWAIT_CONFIG_REG 0x21c0a
> #define V4H_PPI_RW_LPDCOCAL_VT_CONFIG_REG 0x21c0c
> #define V4H_PPI_RW_LPDCOCAL_COARSE_CFG_REG 0x21c10
> +#define V4H_PPI_RW_DDLCAL_CFG_n_REG(n) (0x21c40 + ((n) * 2)) /* n = 0 - 7 */
> #define V4H_PPI_RW_COMMON_CFG_REG 0x21c6c
> #define V4H_PPI_RW_TERMCAL_CFG_0_REG 0x21c80
> #define V4H_PPI_RW_OFFSETCAL_CFG_0_REG 0x21ca0
> @@ -185,6 +186,13 @@ struct rcar_csi2;
> #define V4H_CORE_DIG_IOCTRL_RW_AFE_CB_CTRL_2_REG(n) (0x23840 + ((n) * 2)) /* n = 0 - 11 */
> #define V4H_CORE_DIG_RW_COMMON_REG(n) (0x23880 + ((n) * 2)) /* n = 0 - 15 */
> #define V4H_CORE_DIG_ANACTRL_RW_COMMON_ANACTRL_REG(n) (0x239e0 + ((n) * 2)) /* n = 0 - 3 */
> +#define V4H_CORE_DIG_COMMON_RW_DESKEW_FINE_MEM_REG 0x23fe0
> +
> +#define V4H_CORE_DIG_DLANE_l_RW_CFG_n_REG(l, n) (0x26000 + ((l) * 0x400) + ((n) * 2))
> +#define V4H_CORE_DIG_DLANE_l_RW_LP_n_REG(l, n) (0x26080 + ((l) * 0x400) + ((n) * 2))
> +#define V4H_CORE_DIG_DLANE_l_RW_HS_RX_n_REG(l, n) (0x26100 + ((l) * 0x400) + ((n) * 2))
> +#define V4H_CORE_DIG_DLANE_CLK_RW_LP_n_REG(n) V4H_CORE_DIG_DLANE_l_RW_LP_n_REG(4, (n))
> +#define V4H_CORE_DIG_DLANE_CLK_RW_HS_RX_n_REG(n) V4H_CORE_DIG_DLANE_l_RW_HS_RX_n_REG(4, (n))
>
> /* V4H C-PHY */
> #define V4H_CORE_DIG_RW_TRIO0_REG(n) (0x22100 + ((n) * 2)) /* n = 0 - 3 */
> @@ -1282,11 +1290,193 @@ rcsi2_c_phy_setting_v4h(struct rcar_csi2 *priv, int mbps)
> return conf;
> }
>
> +struct rcsi2_d_phy_setting_v4h_lut_value {
> + unsigned int mbps;
> + unsigned char cfg_1;
> + unsigned char cfg_5_94;
> + unsigned char cfg_5_30;
> + unsigned char lane_ctrl_2_8;
> + unsigned char rw_hs_rx_3_83;
> + unsigned char rw_hs_rx_3_20;
> + unsigned char rw_hs_rx_6;
> + unsigned char rw_hs_rx_1;
> +};
> +
> +static const struct rcsi2_d_phy_setting_v4h_lut_value *
> +rcsi2_d_phy_setting_v4h_lut_lookup(int mbps)
> +{
> + static const struct rcsi2_d_phy_setting_v4h_lut_value values[] = {
> + { 4500, 0x3f, 0x07, 0x00, 0x01, 0x02, 0x01, 0x0d, 0x10 },
> + { 4000, 0x47, 0x08, 0x01, 0x01, 0x05, 0x01, 0x0f, 0x0d },
> + { 3600, 0x4f, 0x09, 0x01, 0x01, 0x06, 0x01, 0x10, 0x0b },
> + { 3230, 0x57, 0x0a, 0x01, 0x01, 0x06, 0x01, 0x12, 0x09 },
> + { 3000, 0x47, 0x08, 0x00, 0x00, 0x03, 0x01, 0x0f, 0x0c },
> + { 2700, 0x4f, 0x09, 0x01, 0x00, 0x06, 0x01, 0x10, 0x0b },
> + { 2455, 0x57, 0x0a, 0x01, 0x00, 0x06, 0x01, 0x12, 0x09 },
> + { 2250, 0x5f, 0x0b, 0x01, 0x00, 0x08, 0x01, 0x13, 0x08 },
> + { 2077, 0x67, 0x0c, 0x01, 0x00, 0x06, 0x02, 0x15, 0x0d },
> + { 1929, 0x6f, 0x0d, 0x02, 0x00, 0x06, 0x02, 0x17, 0x0d },
> + { 1800, 0x77, 0x0e, 0x02, 0x00, 0x06, 0x02, 0x18, 0x0d },
> + { 1688, 0x7f, 0x0f, 0x02, 0x00, 0x08, 0x02, 0x1a, 0x0d },
> + { 1588, 0x87, 0x10, 0x02, 0x00, 0x08, 0x02, 0x1b, 0x0d },
> + { 1500, 0x8f, 0x11, 0x03, 0x00, 0x08, 0x02, 0x1d, 0x0c },
> + };
> +
> + for (unsigned int i = 0; i < ARRAY_SIZE(values); i++)
> + if (mbps >= values[i].mbps)
> + return &values[i];
> +
> + return NULL;
> +}
> +
> +static int rcsi2_d_phy_setting_v4h(struct rcar_csi2 *priv, int mbps)
> +{
> + const struct rcsi2_d_phy_setting_v4h_lut_value *lut =
> + rcsi2_d_phy_setting_v4h_lut_lookup(mbps);
> + u16 val;
> +
> + rcsi2_write16(priv, V4H_CORE_DIG_RW_COMMON_REG(7), 0x0000);
> + rcsi2_write16(priv, V4H_PPI_STARTUP_RW_COMMON_DPHY_REG(7), mbps > 1500 ? 0x0028 : 0x0068);
> + rcsi2_write16(priv, V4H_PPI_STARTUP_RW_COMMON_DPHY_REG(8), 0x0050);
> + rcsi2_write16(priv, V4H_PPI_RW_DDLCAL_CFG_n_REG(0), 0x0063);
> + rcsi2_write16(priv, V4H_PPI_RW_DDLCAL_CFG_n_REG(7), 0x1132);
> + rcsi2_write16(priv, V4H_PPI_RW_DDLCAL_CFG_n_REG(1), 0x1340);
> + rcsi2_write16(priv, V4H_PPI_RW_DDLCAL_CFG_n_REG(2), 0x4b13);
> + rcsi2_write16(priv, V4H_PPI_RW_DDLCAL_CFG_n_REG(4), 0x000a);
> + rcsi2_write16(priv, V4H_PPI_RW_DDLCAL_CFG_n_REG(6), 0x800a);
> + rcsi2_write16(priv, V4H_PPI_RW_DDLCAL_CFG_n_REG(7), 0x1109);
> +
> + if (mbps > 1500) {
> + val = DIV_ROUND_UP(5 * mbps, 64);
> + rcsi2_write16(priv, V4H_PPI_RW_DDLCAL_CFG_n_REG(3), val);
> + }
> +
> + if (lut) {
> + rcsi2_modify16(priv, V4H_PPI_RW_DDLCAL_CFG_n_REG(1),
> + lut->cfg_1, 0x00ff);
> + rcsi2_modify16(priv, V4H_PPI_RW_DDLCAL_CFG_n_REG(5),
> + lut->cfg_5_94 << 4, 0x03f0);
> + rcsi2_modify16(priv, V4H_PPI_RW_DDLCAL_CFG_n_REG(5),
> + lut->cfg_5_30 << 0, 0x000f);
> +
> + for (unsigned int l = 0; l < 5; l++)
> + rcsi2_modify16(priv, V4H_CORE_DIG_IOCTRL_RW_AFE_LANEl_CTRL_2_REG(l, 8),
> + lut->lane_ctrl_2_8 << 12, 0x1000);
> + }
> +
> + for (unsigned int l = 0; l < 4; l++)
> + rcsi2_write16(priv, V4H_CORE_DIG_DLANE_l_RW_LP_n_REG(l, 0), 0x463c);
> +
> + rcsi2_write16(priv, V4H_CORE_DIG_IOCTRL_RW_AFE_LANEl_CTRL_2_REG(0, 2), 0x0000);
> + rcsi2_write16(priv, V4H_CORE_DIG_IOCTRL_RW_AFE_LANEl_CTRL_2_REG(1, 2), 0x0000);
> + rcsi2_write16(priv, V4H_CORE_DIG_IOCTRL_RW_AFE_LANEl_CTRL_2_REG(2, 2), 0x0001);
> + rcsi2_write16(priv, V4H_CORE_DIG_IOCTRL_RW_AFE_LANEl_CTRL_2_REG(3, 2), 0x0000);
> + rcsi2_write16(priv, V4H_CORE_DIG_IOCTRL_RW_AFE_LANEl_CTRL_2_REG(4, 2), 0x0000);
> +
> + rcsi2_write16(priv, V4H_CORE_DIG_RW_COMMON_REG(6), 0x0009);
> +
> + val = mbps > 1500 ? 0x0800 : 0x0802;
> + for (unsigned int l = 0; l < 5; l++)
> + rcsi2_write16(priv, V4H_CORE_DIG_IOCTRL_RW_AFE_LANEl_CTRL_2_REG(l, 12), val);
> +
> + val = mbps > 1500 ? 0x0000 : 0x0002;
> + for (unsigned int l = 0; l < 5; l++)
> + rcsi2_write16(priv, V4H_CORE_DIG_IOCTRL_RW_AFE_LANEl_CTRL_2_REG(l, 13), val);
> +
> + if (mbps >= 80) {
> + /* 2560: 6, 1280: 5, 640: 4, 320: 3, 160: 2, 80: 1 */
> + val = ilog2(mbps / 80) + 1;
> + rcsi2_modify16(priv,
> + V4H_CORE_DIG_IOCTRL_RW_AFE_LANEl_CTRL_2_REG(2, 9),
> + val << 5, 0xe0);
> + }
> +
> + rcsi2_write16(priv, V4H_CORE_DIG_DLANE_CLK_RW_HS_RX_n_REG(0), 0x091c);
> + rcsi2_write16(priv, V4H_CORE_DIG_DLANE_CLK_RW_HS_RX_n_REG(7), 0x3b06);
> +
> + val = DIV_ROUND_UP(1200, mbps) + 12;
> + for (unsigned int l = 0; l < 4; l++)
> + rcsi2_modify16(priv, V4H_CORE_DIG_DLANE_l_RW_HS_RX_n_REG(l, 0), val << 8, 0xf0);
> +
> + val = mbps > 1500 ? 0x0004 : 0x0008;
> + for (unsigned int l = 0; l < 4; l++)
> + rcsi2_write16(priv, V4H_CORE_DIG_DLANE_l_RW_CFG_n_REG(l, 1), val);
> +
> + val = mbps > 2500 ? 0x669a : mbps > 1500 ? 0xe69a : 0xe69b;
> + for (unsigned int l = 0; l < 4; l++)
> + rcsi2_write16(priv, V4H_CORE_DIG_DLANE_l_RW_HS_RX_n_REG(l, 2), val);
> +
> + for (unsigned int l = 0; l < 4; l++)
> + rcsi2_write16(priv, V4H_CORE_DIG_DLANE_l_RW_LP_n_REG(l, 0), 0x163c);
> + rcsi2_write16(priv, V4H_CORE_DIG_DLANE_CLK_RW_LP_n_REG(0), 0x163c);
> +
> + if (lut) {
> + for (unsigned int l = 0; l < 4; l++)
> + rcsi2_modify16(priv, V4H_CORE_DIG_DLANE_l_RW_HS_RX_n_REG(l, 1),
> + lut->rw_hs_rx_1, 0xff);
> + }
> +
> + for (unsigned int l = 0; l < 4; l++)
> + rcsi2_write16(priv, V4H_CORE_DIG_DLANE_l_RW_HS_RX_n_REG(l, 3), 0x9209);
> +
> + for (unsigned int l = 0; l < 4; l++)
> + rcsi2_write16(priv, V4H_CORE_DIG_DLANE_l_RW_HS_RX_n_REG(l, 4), 0x0096);
> +
> + for (unsigned int l = 0; l < 4; l++)
> + rcsi2_write16(priv, V4H_CORE_DIG_DLANE_l_RW_HS_RX_n_REG(l, 5), 0x0100);
> +
> + for (unsigned int l = 0; l < 4; l++)
> + rcsi2_write16(priv, V4H_CORE_DIG_DLANE_l_RW_HS_RX_n_REG(l, 6), 0x2d02);
> +
> + for (unsigned int l = 0; l < 4; l++)
> + rcsi2_write16(priv, V4H_CORE_DIG_DLANE_l_RW_HS_RX_n_REG(l, 7), 0x1b06);
> +
> + if (lut) {
> + /*
> + * Documentation LUT have two values but document writing both
> + * values in a single write.
> + */
> + for (unsigned int l = 0; l < 4; l++)
> + rcsi2_modify16(priv, V4H_CORE_DIG_DLANE_l_RW_HS_RX_n_REG(l, 3),
> + lut->rw_hs_rx_3_83 << 3 | lut->rw_hs_rx_3_20, 0x1ff);
> +
> + for (unsigned int l = 0; l < 4; l++)
> + rcsi2_modify16(priv, V4H_CORE_DIG_DLANE_l_RW_HS_RX_n_REG(l, 6),
> + lut->rw_hs_rx_6 << 8, 0xff00);
> + }
> +
> + static const u16 deskew_fine[] = {
> + 0x0404, 0x040c, 0x0414, 0x041c, 0x0423, 0x0429, 0x0430, 0x043a,
> + 0x0445, 0x044a, 0x0450, 0x045a, 0x0465, 0x0469, 0x0472, 0x047a,
> + 0x0485, 0x0489, 0x0490, 0x049a, 0x04a4, 0x04ac, 0x04b4, 0x04bc,
> + 0x04c4, 0x04cc, 0x04d4, 0x04dc, 0x04e4, 0x04ec, 0x04f4, 0x04fc,
> + 0x0504, 0x050c, 0x0514, 0x051c, 0x0523, 0x0529, 0x0530, 0x053a,
> + 0x0545, 0x054a, 0x0550, 0x055a, 0x0565, 0x0569, 0x0572, 0x057a,
> + 0x0585, 0x0589, 0x0590, 0x059a, 0x05a4, 0x05ac, 0x05b4, 0x05bc,
> + 0x05c4, 0x05cc, 0x05d4, 0x05dc, 0x05e4, 0x05ec, 0x05f4, 0x05fc,
> + 0x0604, 0x060c, 0x0614, 0x061c, 0x0623, 0x0629, 0x0632, 0x063a,
> + 0x0645, 0x064a, 0x0650, 0x065a, 0x0665, 0x0669, 0x0672, 0x067a,
> + 0x0685, 0x0689, 0x0690, 0x069a, 0x06a4, 0x06ac, 0x06b4, 0x06bc,
> + 0x06c4, 0x06cc, 0x06d4, 0x06dc, 0x06e4, 0x06ec, 0x06f4, 0x06fc,
> + 0x0704, 0x070c, 0x0714, 0x071c, 0x0723, 0x072a, 0x0730, 0x073a,
> + 0x0745, 0x074a, 0x0750, 0x075a, 0x0765, 0x0769, 0x0772, 0x077a,
> + 0x0785, 0x0789, 0x0790, 0x079a, 0x07a4, 0x07ac, 0x07b4, 0x07bc,
> + 0x07c4, 0x07cc, 0x07d4, 0x07dc, 0x07e4, 0x07ec, 0x07f4, 0x07fc,
> + };
> +
> + for (unsigned int i = 0; i < ARRAY_SIZE(deskew_fine); i++) {
> + rcsi2_write16(priv, V4H_CORE_DIG_COMMON_RW_DESKEW_FINE_MEM_REG,
> + deskew_fine[i]);
> + }
> +
> + return 0;
> +}
> +
> static int rcsi2_start_receiver_v4h(struct rcar_csi2 *priv,
> struct v4l2_subdev_state *state)
> {
> + const struct rcsi2_cphy_setting *cphy = NULL;
> const struct rcar_csi2_format *format;
> - const struct rcsi2_cphy_setting *cphy;
> const struct v4l2_mbus_framefmt *fmt;
> unsigned int lanes;
> int mbps;
> @@ -1318,7 +1508,8 @@ static int rcsi2_start_receiver_v4h(struct rcar_csi2 *priv,
> rcsi2_write(priv, V4H_FLDC_REG, 0);
> rcsi2_write(priv, V4H_FLDD_REG, 0);
> rcsi2_write(priv, V4H_IDIC_REG, 0);
> - rcsi2_write(priv, V4H_PHY_MODE_REG, V4H_PHY_MODE_CPHY);
> + rcsi2_write(priv, V4H_PHY_MODE_REG,
> + priv->cphy ? V4H_PHY_MODE_CPHY : V4H_PHY_MODE_DPHY);
> rcsi2_write(priv, V4H_N_LANES_REG, lanes - 1);
>
> rcsi2_write(priv, V4M_FRXM_REG,
> @@ -1361,9 +1552,15 @@ static int rcsi2_start_receiver_v4h(struct rcar_csi2 *priv,
> rcsi2_write16(priv, V4H_CORE_DIG_IOCTRL_RW_AFE_CB_CTRL_2_REG(5), 0x4000);
>
> /* T3: PHY settings */
> - cphy = rcsi2_c_phy_setting_v4h(priv, mbps);
> - if (!cphy)
> - return -ERANGE;
> + if (priv->cphy) {
> + cphy = rcsi2_c_phy_setting_v4h(priv, mbps);
> + if (!cphy)
> + return -ERANGE;
> + } else {
> + ret = rcsi2_d_phy_setting_v4h(priv, mbps);
> + if (ret)
> + return ret;
> + }
>
> /* T4: Leave Shutdown mode */
> rcsi2_write(priv, V4H_DPHY_RSTZ_REG, BIT(0));
> @@ -1376,11 +1573,23 @@ static int rcsi2_start_receiver_v4h(struct rcar_csi2 *priv,
> }
>
> /* T6: Analog programming */
> - for (unsigned int l = 0; l < 3; l++) {
> - rcsi2_write16(priv, V4H_CORE_DIG_IOCTRL_RW_AFE_LANEl_CTRL_2_REG(l, 9),
> - cphy->lane29);
> - rcsi2_write16(priv, V4H_CORE_DIG_IOCTRL_RW_AFE_LANEl_CTRL_2_REG(l, 7),
> - cphy->lane27);
> + if (priv->cphy) {
> + for (unsigned int l = 0; l < 3; l++) {
> + rcsi2_write16(priv, V4H_CORE_DIG_IOCTRL_RW_AFE_LANEl_CTRL_2_REG(l, 9),
> + cphy->lane29);
> + rcsi2_write16(priv, V4H_CORE_DIG_IOCTRL_RW_AFE_LANEl_CTRL_2_REG(l, 7),
> + cphy->lane27);
> + }
> + } else {
> + u16 val_2_9 = mbps > 2500 ? 0x14 : mbps > 1500 ? 0x04 : 0x00;
> + u16 val_2_15 = mbps > 1500 ? 0x03 : 0x00;
> +
> + for (unsigned int l = 0; l < 5; l++) {
> + rcsi2_write16(priv, V4H_CORE_DIG_IOCTRL_RW_AFE_LANEl_CTRL_2_REG(l, 9),
> + val_2_9);
> + rcsi2_write16(priv, V4H_CORE_DIG_IOCTRL_RW_AFE_LANEl_CTRL_2_REG(l, 15),
> + val_2_15);
> + }
> }
>
> /* T7: Wait for stop state */
> @@ -2245,6 +2454,7 @@ static const struct rcar_csi2_info rcar_csi2_info_r8a779g0 = {
> .start_receiver = rcsi2_start_receiver_v4h,
> .use_isp = true,
> .support_cphy = true,
> + .support_dphy = true,
> };
>
> static const struct rcsi2_register_layout rcsi2_registers_v4m = {
--
Regards,
Laurent Pinchart
^ permalink raw reply [flat|nested] 6+ messages in thread
end of thread, other threads:[~2025-06-12 22:21 UTC | newest]
Thread overview: 6+ messages (download: mbox.gz follow: Atom feed
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2025-06-12 17:59 [PATCH v4 0/4] media: rcar-csi2: Add D-PHY support for V4H Niklas Söderlund
2025-06-12 17:59 ` [PATCH v4 1/4] media: rcar-csi2: Clarify usage of mbps and msps Niklas Söderlund
2025-06-12 17:59 ` [PATCH v4 2/4] media: rcar-csi2: Rework macros to access AFE lanes Niklas Söderlund
2025-06-12 17:59 ` [PATCH v4 3/4] media: rcar-csi2: Update start procedure for V4H Niklas Söderlund
2025-06-12 17:59 ` [PATCH v4 4/4] media: rcar-csi2: Add D-PHY support " Niklas Söderlund
2025-06-12 22:21 ` Laurent Pinchart
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