[PATCH v3 1/9] soc: renesas: rz-sysc: Add syscon/regmap support

Claudiu
2025-07-04T16:31:40Z

From: John Madieu <john.madieu.xa@bp.renesas.com>

The RZ/G3E system controller has various registers that control or report
some properties specific to individual IPs. The regmap is registered as a
syscon device to allow these IP drivers to access the registers through the
regmap API.

As other RZ SoCs might have custom read/write callbacks or max-offsets,
add register a custom regmap configuration.

Signed-off-by: John Madieu <john.madieu.xa@bp.renesas.com>
Tested-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
[claudiu.beznea:
- s/rzg3e_sysc_regmap/rzv2h_sysc_regmap in RZ/V2H sysc
file
- do not check the match->data validity in rz_sysc_probe() as it is
always valid
- register the regmap if data->regmap_cfg is valid]
Signed-off-by: Claudiu Beznea <claudiu.beznea.uj@bp.renesas.com>
---

Changes in v3:
- collected tags

Changes in v2:
- picked the latest version from John after he addressed the review
comments received at [1];
- I adjusted as specified in the SoB area

[1] https://lore.kernel.org/all/20250330214945.185725-2-john.madieu.xa@bp.renesas.com/

drivers/soc/renesas/Kconfig | 1 +
drivers/soc/renesas/r9a08g045-sysc.c | 10 ++++++++++
drivers/soc/renesas/r9a09g047-sys.c | 10 ++++++++++
drivers/soc/renesas/r9a09g057-sys.c | 10 ++++++++++
drivers/soc/renesas/rz-sysc.c | 17 ++++++++++++++++-
drivers/soc/renesas/rz-sysc.h | 3 +++
6 files changed, 50 insertions(+), 1 deletion(-)

diff --git a/drivers/soc/renesas/Kconfig b/drivers/soc/renesas/Kconfig
index 1930a12b8fa7..58a4ab2643d6 100644
--- a/drivers/soc/renesas/Kconfig
+++ b/drivers/soc/renesas/Kconfig
@@ -452,6 +452,7 @@ config RST_RCAR

config SYSC_RZ
bool "System controller for RZ SoCs" if COMPILE_TEST
+ select MFD_SYSCON

config SYSC_R9A08G045
bool "Renesas System controller support for R9A08G045 (RZ/G3S)" if COMPILE_TEST
diff --git a/drivers/soc/renesas/r9a08g045-sysc.c b/drivers/soc/renesas/r9a08g045-sysc.c
index f4db1431e036..0ef6df77e25f 100644
--- a/drivers/soc/renesas/r9a08g045-sysc.c
+++ b/drivers/soc/renesas/r9a08g045-sysc.c
@@ -18,6 +18,16 @@ static const struct rz_sysc_soc_id_init_data rzg3s_sysc_soc_id_init_data __initc
.specific_id_mask = GENMASK(27, 0),
};

+static const struct regmap_config rzg3s_sysc_regmap __initconst = {
+ .name = "rzg3s_sysc_regs",
+ .reg_bits = 32,
+ .reg_stride = 4,
+ .val_bits = 32,
+ .fast_io = true,
+ .max_register = 0xe20,
+};
+
const struct rz_sysc_init_data rzg3s_sysc_init_data __initconst = {
.soc_id_init_data = &rzg3s_sysc_soc_id_init_data,
+ .regmap_cfg = &rzg3s_sysc_regmap,
};
diff --git a/drivers/soc/renesas/r9a09g047-sys.c b/drivers/soc/renesas/r9a09g047-sys.c
index cd2eb7782cfe..a3acf6dd2867 100644
--- a/drivers/soc/renesas/r9a09g047-sys.c
+++ b/drivers/soc/renesas/r9a09g047-sys.c
@@ -62,6 +62,16 @@ static const struct rz_sysc_soc_id_init_data rzg3e_sys_soc_id_init_data __initco
.print_id = rzg3e_sys_print_id,
};

+static const struct regmap_config rzg3e_sysc_regmap __initconst = {
+ .name = "rzg3e_sysc_regs",
+ .reg_bits = 32,
+ .reg_stride = 4,
+ .val_bits = 32,
+ .fast_io = true,
+ .max_register = 0x170c,
+};
+
const struct rz_sysc_init_data rzg3e_sys_init_data = {
.soc_id_init_data = &rzg3e_sys_soc_id_init_data,
+ .regmap_cfg = &rzg3e_sysc_regmap,
};
diff --git a/drivers/soc/renesas/r9a09g057-sys.c b/drivers/soc/renesas/r9a09g057-sys.c
index 4c21cc29edbc..c26821636dce 100644
--- a/drivers/soc/renesas/r9a09g057-sys.c
+++ b/drivers/soc/renesas/r9a09g057-sys.c
@@ -62,6 +62,16 @@ static const struct rz_sysc_soc_id_init_data rzv2h_sys_soc_id_init_data __initco
.print_id = rzv2h_sys_print_id,
};

+static const struct regmap_config rzv2h_sysc_regmap __initconst = {
+ .name = "rzv2h_sysc_regs",
+ .reg_bits = 32,
+ .reg_stride = 4,
+ .val_bits = 32,
+ .fast_io = true,
+ .max_register = 0x170c,
+};
+
const struct rz_sysc_init_data rzv2h_sys_init_data = {
.soc_id_init_data = &rzv2h_sys_soc_id_init_data,
+ .regmap_cfg = &rzv2h_sysc_regmap,
};
diff --git a/drivers/soc/renesas/rz-sysc.c b/drivers/soc/renesas/rz-sysc.c
index ffa65fb4dade..70556a2f55e6 100644
--- a/drivers/soc/renesas/rz-sysc.c
+++ b/drivers/soc/renesas/rz-sysc.c
@@ -6,8 +6,10 @@
*/

#include <linux/io.h>
+#include <linux/mfd/syscon.h>
#include <linux/of.h>
#include <linux/platform_device.h>
+#include <linux/regmap.h>
#include <linux/sys_soc.h>

#include "rz-sysc.h"
@@ -100,14 +102,19 @@ MODULE_DEVICE_TABLE(of, rz_sysc_match);

static int rz_sysc_probe(struct platform_device *pdev)
{
+ const struct rz_sysc_init_data *data;
const struct of_device_id *match;
struct device *dev = &pdev->dev;
+ struct regmap *regmap;
struct rz_sysc *sysc;
+ int ret;

match = of_match_node(rz_sysc_match, dev->of_node);
if (!match)
return -ENODEV;

+ data = match->data;
+
sysc = devm_kzalloc(dev, sizeof(*sysc), GFP_KERNEL);
if (!sysc)
return -ENOMEM;
@@ -117,7 +124,15 @@ static int rz_sysc_probe(struct platform_device *pdev)
return PTR_ERR(sysc->base);

sysc->dev = dev;
- return rz_sysc_soc_init(sysc, match);
+ ret = rz_sysc_soc_init(sysc, match);
+ if (ret || !data->regmap_cfg)
+ return ret;
+
+ regmap = devm_regmap_init_mmio(dev, sysc->base, data->regmap_cfg);
+ if (IS_ERR(regmap))
+ return PTR_ERR(regmap);
+
+ return of_syscon_register_regmap(dev->of_node, regmap);
}

static struct platform_driver rz_sysc_driver = {
diff --git a/drivers/soc/renesas/rz-sysc.h b/drivers/soc/renesas/rz-sysc.h
index 56bc047a1bff..447008140634 100644
--- a/drivers/soc/renesas/rz-sysc.h
+++ b/drivers/soc/renesas/rz-sysc.h
@@ -9,6 +9,7 @@
#define __SOC_RENESAS_RZ_SYSC_H__

#include <linux/device.h>
+#include <linux/regmap.h>
#include <linux/sys_soc.h>
#include <linux/types.h>

@@ -34,9 +35,11 @@ struct rz_sysc_soc_id_init_data {
/**
* struct rz_sysc_init_data - RZ SYSC initialization data
* @soc_id_init_data: RZ SYSC SoC ID initialization data
+ * @regmap_cfg: SoC-specific regmap config
*/
struct rz_sysc_init_data {
const struct rz_sysc_soc_id_init_data *soc_id_init_data;
+ const struct regmap_config *regmap_cfg;
};

extern const struct rz_sysc_init_data rzg3e_sys_init_data;
--
2.43.0