[PATCH 11/17] drm: renesas: rz-du: mipi_dsi: Add OF data support

Prabhakar
2025-03-30T21:08:17Z

From: Lad Prabhakar <prabhakar.mahadev-lad.rj@bp.renesas.com>

In preparation for adding support for the Renesas RZ/V2H(P) SoC, this patch
introduces a mechanism to pass SoC-specific information via OF data in the
DSI driver. This enables the driver to adapt dynamically to various
SoC-specific requirements without hardcoding configurations.

The MIPI DSI interface on the RZ/V2H(P) SoC is nearly identical to the one
on the RZ/G2L SoC. While the LINK registers are shared between the two
SoCs, the D-PHY registers differ. Also the VCLK range differs on both these
SoCs. To accommodate these differences `struct rzg2l_mipi_dsi_hw_info` is
introduced and as now passed as OF data.

These changes lay the groundwork for the upcoming RZ/V2H(P) SoC support by
allowing SoC-specific data to be passed through OF.

Co-developed-by: Fabrizio Castro <fabrizio.castro.jz@renesas.com>
Signed-off-by: Fabrizio Castro <fabrizio.castro.jz@renesas.com>
Signed-off-by: Lad Prabhakar <prabhakar.mahadev-lad.rj@bp.renesas.com>
---
.../gpu/drm/renesas/rz-du/rzg2l_mipi_dsi.c | 66 ++++++++++++++-----
.../drm/renesas/rz-du/rzg2l_mipi_dsi_regs.h | 2 -
2 files changed, 49 insertions(+), 19 deletions(-)

diff --git a/drivers/gpu/drm/renesas/rz-du/rzg2l_mipi_dsi.c b/drivers/gpu/drm/renesas/rz-du/rzg2l_mipi_dsi.c
index e0379f099659..44b95082b29c 100644
--- a/drivers/gpu/drm/renesas/rz-du/rzg2l_mipi_dsi.c
+++ b/drivers/gpu/drm/renesas/rz-du/rzg2l_mipi_dsi.c
@@ -28,10 +28,24 @@

#include "rzg2l_mipi_dsi_regs.h"

+struct rzg2l_mipi_dsi;
+
+struct rzg2l_mipi_dsi_hw_info {
+ int (*dphy_init)(struct rzg2l_mipi_dsi *dsi, unsigned long hsfreq);
+ void (*dphy_exit)(struct rzg2l_mipi_dsi *dsi);
+ u32 phy_reg_offset;
+ u32 link_reg_offset;
+ unsigned long max_dclk;
+ unsigned long min_dclk;
+ bool has_dphy_rstc;
+};
+
struct rzg2l_mipi_dsi {
struct device *dev;
void __iomem *mmio;

+ const struct rzg2l_mipi_dsi_hw_info *info;
+
struct reset_control *rstc;
struct reset_control *arstc;
struct reset_control *prstc;
@@ -164,22 +178,22 @@ static const struct rzg2l_mipi_dsi_timings rzg2l_mipi_dsi_global_timings[] = {

static void rzg2l_mipi_dsi_phy_write(struct rzg2l_mipi_dsi *dsi, u32 reg, u32 data)
{
- iowrite32(data, dsi->mmio + reg);
+ iowrite32(data, dsi->mmio + dsi->info->phy_reg_offset + reg);
}

static void rzg2l_mipi_dsi_link_write(struct rzg2l_mipi_dsi *dsi, u32 reg, u32 data)
{
- iowrite32(data, dsi->mmio + LINK_REG_OFFSET + reg);
+ iowrite32(data, dsi->mmio + dsi->info->link_reg_offset + reg);
}

static u32 rzg2l_mipi_dsi_phy_read(struct rzg2l_mipi_dsi *dsi, u32 reg)
{
- return ioread32(dsi->mmio + reg);
+ return ioread32(dsi->mmio + dsi->info->phy_reg_offset + reg);
}

static u32 rzg2l_mipi_dsi_link_read(struct rzg2l_mipi_dsi *dsi, u32 reg)
{
- return ioread32(dsi->mmio + LINK_REG_OFFSET + reg);
+ return ioread32(dsi->mmio + dsi->info->link_reg_offset + reg);
}

/* -----------------------------------------------------------------------------
@@ -291,7 +305,7 @@ static int rzg2l_mipi_dsi_startup(struct rzg2l_mipi_dsi *dsi,
vclk_rate = clk_get_rate(dsi->vclk);
hsfreq = DIV_ROUND_CLOSEST_ULL(vclk_rate * bpp, dsi->lanes);

- ret = rzg2l_mipi_dsi_dphy_init(dsi, hsfreq);
+ ret = dsi->info->dphy_init(dsi, hsfreq);
if (ret < 0)
goto err_phy;

@@ -334,7 +348,7 @@ static int rzg2l_mipi_dsi_startup(struct rzg2l_mipi_dsi *dsi,
return 0;

err_phy:
- rzg2l_mipi_dsi_dphy_exit(dsi);
+ dsi->info->dphy_exit(dsi);
pm_runtime_put(dsi->dev);

return ret;
@@ -342,7 +356,7 @@ static int rzg2l_mipi_dsi_startup(struct rzg2l_mipi_dsi *dsi,

static void rzg2l_mipi_dsi_stop(struct rzg2l_mipi_dsi *dsi)
{
- rzg2l_mipi_dsi_dphy_exit(dsi);
+ dsi->info->dphy_exit(dsi);
pm_runtime_put(dsi->dev);
}

@@ -585,10 +599,12 @@ rzg2l_mipi_dsi_bridge_mode_valid(struct drm_bridge *bridge,
const struct drm_display_info *info,
const struct drm_display_mode *mode)
{
- if (mode->clock > 148500)
+ struct rzg2l_mipi_dsi *dsi = bridge_to_rzg2l_mipi_dsi(bridge);
+
+ if (mode->clock > dsi->info->max_dclk)
return MODE_CLOCK_HIGH;

- if (mode->clock < 5803)
+ if (mode->clock < dsi->info->min_dclk)
return MODE_CLOCK_LOW;

return MODE_OK;
@@ -714,6 +730,11 @@ static int rzg2l_mipi_dsi_probe(struct platform_device *pdev)
platform_set_drvdata(pdev, dsi);
dsi->dev = &pdev->dev;

+ dsi->info = of_device_get_match_data(&pdev->dev);
+ if (!dsi->info)
+ return dev_err_probe(dsi->dev, -ENODEV,
+ "missing data info\n");
+
ret = drm_of_get_data_lanes_count_ep(dsi->dev->of_node, 1, 0, 1, 4);
if (ret < 0)
return dev_err_probe(dsi->dev, ret,
@@ -729,10 +750,12 @@ static int rzg2l_mipi_dsi_probe(struct platform_device *pdev)
if (IS_ERR(dsi->vclk))
return PTR_ERR(dsi->vclk);

- dsi->rstc = devm_reset_control_get_exclusive(dsi->dev, "rst");
- if (IS_ERR(dsi->rstc))
- return dev_err_probe(dsi->dev, PTR_ERR(dsi->rstc),
- "failed to get rst\n");
+ if (dsi->info->has_dphy_rstc) {
+ dsi->rstc = devm_reset_control_get_exclusive(dsi->dev, "rst");
+ if (IS_ERR(dsi->rstc))
+ return dev_err_probe(dsi->dev, PTR_ERR(dsi->rstc),
+ "failed to get rst\n");
+ }

dsi->arstc = devm_reset_control_get_exclusive(dsi->dev, "arst");
if (IS_ERR(dsi->arstc))
@@ -757,13 +780,13 @@ static int rzg2l_mipi_dsi_probe(struct platform_device *pdev)
* mode->clock and format are not available. So initialize DPHY with
* timing parameters for 80Mbps.
*/
- ret = rzg2l_mipi_dsi_dphy_init(dsi, 80000000);
+ ret = dsi->info->dphy_init(dsi, 80000000);
if (ret < 0)
goto err_phy;

txsetr = rzg2l_mipi_dsi_link_read(dsi, TXSETR);
dsi->num_data_lanes = min(((txsetr >> 16) & 3) + 1, num_data_lanes);
- rzg2l_mipi_dsi_dphy_exit(dsi);
+ dsi->info->dphy_exit(dsi);
pm_runtime_put(dsi->dev);

/* Initialize the DRM bridge. */
@@ -780,7 +803,7 @@ static int rzg2l_mipi_dsi_probe(struct platform_device *pdev)
return 0;

err_phy:
- rzg2l_mipi_dsi_dphy_exit(dsi);
+ dsi->info->dphy_exit(dsi);
pm_runtime_put(dsi->dev);
err_pm_disable:
pm_runtime_disable(dsi->dev);
@@ -795,8 +818,17 @@ static void rzg2l_mipi_dsi_remove(struct platform_device *pdev)
pm_runtime_disable(&pdev->dev);
}

+static const struct rzg2l_mipi_dsi_hw_info rzg2l_mipi_dsi_info = {
+ .dphy_init = rzg2l_mipi_dsi_dphy_init,
+ .dphy_exit = rzg2l_mipi_dsi_dphy_exit,
+ .has_dphy_rstc = true,
+ .link_reg_offset = 0x10000,
+ .max_dclk = 148500,
+ .min_dclk = 5803,
+};
+
static const struct of_device_id rzg2l_mipi_dsi_of_table[] = {
- { .compatible = "renesas,rzg2l-mipi-dsi" },
+ { .compatible = "renesas,rzg2l-mipi-dsi", .data = &rzg2l_mipi_dsi_info, },
{ /* sentinel */ }
};

diff --git a/drivers/gpu/drm/renesas/rz-du/rzg2l_mipi_dsi_regs.h b/drivers/gpu/drm/renesas/rz-du/rzg2l_mipi_dsi_regs.h
index 1dbc16ec64a4..16efe4dc59f4 100644
--- a/drivers/gpu/drm/renesas/rz-du/rzg2l_mipi_dsi_regs.h
+++ b/drivers/gpu/drm/renesas/rz-du/rzg2l_mipi_dsi_regs.h
@@ -41,8 +41,6 @@
#define DSIDPHYTIM3_THS_ZERO(x) ((x) << 0)

/* --------------------------------------------------------*/
-/* Link Registers */
-#define LINK_REG_OFFSET 0x10000

/* Link Status Register */
#define LINKSR 0x10
--
2.49.0