When hotpluging policy cpu, cpu policy init will be called multiple times.
Unplug CPU7 -> CPU6 -> CPU5 -> CPU4, then plug CPU4 again.
In this case, devm_remap will double remap and resource allocate fail.
So replace devm_remap to ioremap and release related resources in cpu exit.
Hector.Yuan (1):
cpufreq: mediatek-hw: Fix double devm_remap in hotplug case
drivers/cpufreq/mediatek-cpufreq-hw.c | 33 ++++++++++++++++++++++++++++++---
1 file changed, 30 insertions(+), 3 deletions(-)
From: "Hector.Yuan" <[email protected]>
When hotpluging policy cpu, cpu policy init will be called multiple times.
Unplug CPU7 -> CPU6 -> CPU5 -> CPU4, then plug CPU4 again.
In this case, devm_remap will double remap and resource allocate fail.
So replace devm_remap to ioremap and release resources in cpu policy exit.
Signed-off-by: Hector.Yuan <[email protected]>
---
drivers/cpufreq/mediatek-cpufreq-hw.c | 33 ++++++++++++++++++++++++++++++---
1 file changed, 30 insertions(+), 3 deletions(-)
diff --git a/drivers/cpufreq/mediatek-cpufreq-hw.c b/drivers/cpufreq/mediatek-cpufreq-hw.c
index 0cf18dd..25317d7 100644
--- a/drivers/cpufreq/mediatek-cpufreq-hw.c
+++ b/drivers/cpufreq/mediatek-cpufreq-hw.c
@@ -36,6 +36,8 @@ enum {
struct mtk_cpufreq_data {
struct cpufreq_frequency_table *table;
void __iomem *reg_bases[REG_ARRAY_SIZE];
+ struct resource *res;
+ void __iomem *base;
int nr_opp;
};
@@ -156,6 +158,7 @@ static int mtk_cpu_resources_init(struct platform_device *pdev,
{
struct mtk_cpufreq_data *data;
struct device *dev = &pdev->dev;
+ struct resource *res;
void __iomem *base;
int ret, i;
int index;
@@ -170,9 +173,26 @@ static int mtk_cpu_resources_init(struct platform_device *pdev,
if (index < 0)
return index;
- base = devm_platform_ioremap_resource(pdev, index);
- if (IS_ERR(base))
- return PTR_ERR(base);
+ res = platform_get_resource(pdev, IORESOURCE_MEM, index);
+ if (!res) {
+ dev_err(dev, "failed to get mem resource %d\n", index);
+ return -ENODEV;
+ }
+
+ if (!request_mem_region(res->start, resource_size(res), res->name)) {
+ dev_err(dev, "failed to request resource %pR\n", res);
+ return -EBUSY;
+ }
+
+ base = ioremap(res->start, resource_size(res));
+ if (!base) {
+ dev_err(dev, "failed to map resource %pR\n", res);
+ ret = -ENOMEM;
+ goto release_region;
+ }
+
+ data->base = base;
+ data->res = res;
for (i = REG_FREQ_LUT_TABLE; i < REG_ARRAY_SIZE; i++)
data->reg_bases[i] = base + offsets[i];
@@ -187,6 +207,9 @@ static int mtk_cpu_resources_init(struct platform_device *pdev,
policy->driver_data = data;
return 0;
+release_region:
+ release_mem_region(res->start, resource_size(res));
+ return ret;
}
static int mtk_cpufreq_hw_cpu_init(struct cpufreq_policy *policy)
@@ -233,9 +256,13 @@ static int mtk_cpufreq_hw_cpu_init(struct cpufreq_policy *policy)
static int mtk_cpufreq_hw_cpu_exit(struct cpufreq_policy *policy)
{
struct mtk_cpufreq_data *data = policy->driver_data;
+ struct resource *res = data->res;
+ void __iomem *base = data->base;
/* HW should be in paused state now */
writel_relaxed(0x0, data->reg_bases[REG_FREQ_ENABLE]);
+ iounmap(base);
+ release_mem_region(res->start, resource_size(res));
return 0;
}
--
1.7.9.5
On 29-10-21, 19:42, Hector Yuan wrote:
> From: "Hector.Yuan" <[email protected]>
>
> When hotpluging policy cpu, cpu policy init will be called multiple times.
> Unplug CPU7 -> CPU6 -> CPU5 -> CPU4, then plug CPU4 again.
> In this case, devm_remap will double remap and resource allocate fail.
> So replace devm_remap to ioremap and release resources in cpu policy exit.
>
> Signed-off-by: Hector.Yuan <[email protected]>
> ---
> drivers/cpufreq/mediatek-cpufreq-hw.c | 33 ++++++++++++++++++++++++++++++---
> 1 file changed, 30 insertions(+), 3 deletions(-)
>
> diff --git a/drivers/cpufreq/mediatek-cpufreq-hw.c b/drivers/cpufreq/mediatek-cpufreq-hw.c
> index 0cf18dd..25317d7 100644
> --- a/drivers/cpufreq/mediatek-cpufreq-hw.c
> +++ b/drivers/cpufreq/mediatek-cpufreq-hw.c
> @@ -36,6 +36,8 @@ enum {
> struct mtk_cpufreq_data {
> struct cpufreq_frequency_table *table;
> void __iomem *reg_bases[REG_ARRAY_SIZE];
> + struct resource *res;
> + void __iomem *base;
> int nr_opp;
> };
>
> @@ -156,6 +158,7 @@ static int mtk_cpu_resources_init(struct platform_device *pdev,
pdev specific initializations shouldn't be done from policy->init(),
but instead do those only once from mtk_cpufreq_hw_driver_probe().
That way such bugs won't occur again.
--
viresh
On 29-10-21, 19:42, Hector Yuan wrote:
> From: "Hector.Yuan" <[email protected]>
>
> When hotpluging policy cpu, cpu policy init will be called multiple times.
> Unplug CPU7 -> CPU6 -> CPU5 -> CPU4, then plug CPU4 again.
> In this case, devm_remap will double remap and resource allocate fail.
> So replace devm_remap to ioremap and release resources in cpu policy exit.
>
> Signed-off-by: Hector.Yuan <[email protected]>
> ---
> drivers/cpufreq/mediatek-cpufreq-hw.c | 33 ++++++++++++++++++++++++++++++---
> 1 file changed, 30 insertions(+), 3 deletions(-)
Applied. Thanks.
--
viresh