2023-03-15 07:54:39

by Chunyan Zhang

Subject: [PATCH] clk: sprd: set max_register according to mapping range

In sprd clock driver, regmap_config.max_register was set to a fixed value
which is likely larger than the address range configured in device tree,
when reading registers through debugfs it would cause access violation.

Signed-off-by: Chunyan Zhang <[email protected]>
---
drivers/clk/sprd/common.c | 9 ++++++---
1 file changed, 6 insertions(+), 3 deletions(-)

diff --git a/drivers/clk/sprd/common.c b/drivers/clk/sprd/common.c
index ce81e4087a8f..2bfbab8db94b 100644
--- a/drivers/clk/sprd/common.c
+++ b/drivers/clk/sprd/common.c
@@ -17,7 +17,6 @@ static const struct regmap_config sprdclk_regmap_config = {
.reg_bits = 32,
.reg_stride = 4,
.val_bits = 32,
- .max_register = 0xffff,
.fast_io = true,
};

@@ -43,6 +42,8 @@ int sprd_clk_regmap_init(struct platform_device *pdev,
struct device *dev = &pdev->dev;
struct device_node *node = dev->of_node, *np;
struct regmap *regmap;
+ struct resource *res;
+ struct regmap_config reg_config = sprdclk_regmap_config;

if (of_find_property(node, "sprd,syscon", NULL)) {
regmap = syscon_regmap_lookup_by_phandle(node, "sprd,syscon");
@@ -59,12 +60,14 @@ int sprd_clk_regmap_init(struct platform_device *pdev,
return PTR_ERR(regmap);
}
} else {
- base = devm_platform_ioremap_resource(pdev, 0);
+ base = devm_platform_get_and_ioremap_resource(pdev, 0, &res);
if (IS_ERR(base))
return PTR_ERR(base);

+ reg_config.max_register = resource_size(res) - reg_config.reg_stride;
+
regmap = devm_regmap_init_mmio(&pdev->dev, base,
- &sprdclk_regmap_config);
+ &reg_config);
if (IS_ERR(regmap)) {
pr_err("failed to init regmap\n");
return PTR_ERR(regmap);
--
2.25.1

2023-03-15 18:45:15

by Stephen Boyd

Subject: Re: [PATCH] clk: sprd: set max_register according to mapping range

Quoting Chunyan Zhang (2023-03-15 00:53:43)
> In sprd clock driver, regmap_config.max_register was set to a fixed value
> which is likely larger than the address range configured in device tree,
> when reading registers through debugfs it would cause access violation.
>
> Signed-off-by: Chunyan Zhang <[email protected]>

Any Fixes tag?