[PATCH v4 1/8] soc: renesas: rz-sysc: Add syscon/regmap support
From: Claudiu
Date: Fri Aug 08 2025 - 02:18:42 EST
From: John Madieu <john.madieu.xa@xxxxxxxxxxxxxx>
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,
register a custom regmap configuration.
Signed-off-by: John Madieu <john.madieu.xa@xxxxxxxxxxxxxx>
[claudiu.beznea:
- do not check the match->data validity in rz_sysc_probe() as it is
always valid
- dinamically allocate regmap_cfg]
Signed-off-by: Claudiu Beznea <claudiu.beznea.uj@xxxxxxxxxxxxxx>
---
Changes in v4:
- adjusted the patch description by dropping "add" from
"add register a custom regmap configuration"
- updated the list of changes from Claudiu Beznea
- dynamically allocate the regmap_config as proposed at [2]
- this patch is needed for proper function of USB (as proposed in this
series) that being the reason it is introduced here, as well
[2] https://lore.kernel.org/all/CAMuHMdVyf3Xtpw=LWHrnD2CVQX4xYm=FBHvY_dx9OesHDz5zNg@xxxxxxxxxxxxxx/
Changes in v3:
- none, this patch is new, it was picked from John after he addressed
the review comments received at [1];
- I adjusted as specified in the SoB area, and included it here as it
is the base for the signal support presented in the next commits
[1] https://lore.kernel.org/all/20250330214945.185725-2-john.madieu.xa@xxxxxxxxxxxxxx/
drivers/soc/renesas/Kconfig | 1 +
drivers/soc/renesas/r9a08g045-sysc.c | 1 +
drivers/soc/renesas/r9a09g047-sys.c | 1 +
drivers/soc/renesas/r9a09g057-sys.c | 1 +
drivers/soc/renesas/rz-sysc.c | 29 +++++++++++++++++++++++++++-
drivers/soc/renesas/rz-sysc.h | 2 ++
6 files changed, 34 insertions(+), 1 deletion(-)
diff --git a/drivers/soc/renesas/Kconfig b/drivers/soc/renesas/Kconfig
index 719b7f4f376f..c97e2a183388 100644
--- a/drivers/soc/renesas/Kconfig
+++ b/drivers/soc/renesas/Kconfig
@@ -449,6 +449,7 @@ 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..0504d4e68761 100644
--- a/drivers/soc/renesas/r9a08g045-sysc.c
+++ b/drivers/soc/renesas/r9a08g045-sysc.c
@@ -20,4 +20,5 @@ static const struct rz_sysc_soc_id_init_data rzg3s_sysc_soc_id_init_data __initc
const struct rz_sysc_init_data rzg3s_sysc_init_data __initconst = {
.soc_id_init_data = &rzg3s_sysc_soc_id_init_data,
+ .max_register = 0xe20,
};
diff --git a/drivers/soc/renesas/r9a09g047-sys.c b/drivers/soc/renesas/r9a09g047-sys.c
index cd2eb7782cfe..2e8426c03050 100644
--- a/drivers/soc/renesas/r9a09g047-sys.c
+++ b/drivers/soc/renesas/r9a09g047-sys.c
@@ -64,4 +64,5 @@ static const struct rz_sysc_soc_id_init_data rzg3e_sys_soc_id_init_data __initco
const struct rz_sysc_init_data rzg3e_sys_init_data = {
.soc_id_init_data = &rzg3e_sys_soc_id_init_data,
+ .max_register = 0x170c,
};
diff --git a/drivers/soc/renesas/r9a09g057-sys.c b/drivers/soc/renesas/r9a09g057-sys.c
index 4c21cc29edbc..e3390e7c7fe5 100644
--- a/drivers/soc/renesas/r9a09g057-sys.c
+++ b/drivers/soc/renesas/r9a09g057-sys.c
@@ -64,4 +64,5 @@ static const struct rz_sysc_soc_id_init_data rzv2h_sys_soc_id_init_data __initco
const struct rz_sysc_init_data rzv2h_sys_init_data = {
.soc_id_init_data = &rzv2h_sys_soc_id_init_data,
+ .max_register = 0x170c,
};
diff --git a/drivers/soc/renesas/rz-sysc.c b/drivers/soc/renesas/rz-sysc.c
index ffa65fb4dade..66cc8d01f096 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 +102,20 @@ 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 regmap_config *regmap_cfg;
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 +125,26 @@ 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)
+ return ret;
+
+ regmap_cfg = devm_kzalloc(dev, sizeof(*regmap_cfg), GFP_KERNEL);
+ if (!regmap_cfg)
+ return -ENOMEM;
+
+ regmap_cfg->name = "rz_sysc_regs";
+ regmap_cfg->reg_bits = 32;
+ regmap_cfg->reg_stride = 4;
+ regmap_cfg->val_bits = 32;
+ regmap_cfg->fast_io = true;
+ regmap_cfg->max_register = data->max_register;
+
+ regmap = devm_regmap_init_mmio(dev, sysc->base, 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..8eec355d5d56 100644
--- a/drivers/soc/renesas/rz-sysc.h
+++ b/drivers/soc/renesas/rz-sysc.h
@@ -34,9 +34,11 @@ 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
+ * @max_register: Maximum SYSC register offset to be used by the regmap config
*/
struct rz_sysc_init_data {
const struct rz_sysc_soc_id_init_data *soc_id_init_data;
+ u32 max_register;
};
extern const struct rz_sysc_init_data rzg3e_sys_init_data;
--
2.43.0