Skip to content

watchdog: wdat_wdt: map registers that fall inside ACPI NVS #270

New issue

Have a question about this project? Sign up for a free GitHub account to open an issue and contact its maintainers and the community.

Sign up for GitHub

By clicking “Sign up for GitHub”, you agree to our terms of service and privacy statement. We’ll occasionally send you account related emails.

Already on GitHub? Sign in to your account

Merged
rucoder merged 1 commit into from
Aug 17, 2026
+26 −1
Merged

watchdog: wdat_wdt: map registers that fall inside ACPI NVS #270

Changes from all commits
Commits
Show all changes
1 commit
Select commit
File filter

Filter by extension

Filter by extension
Conversations
Failed to load comments.
Loading
Jump to
Jump to file
Failed to load files.
Loading
Diff view
Diff view
27 changes: 26 additions & 1 deletion drivers/watchdog/wdat_wdt.c
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -7,7 +7,9 @@
*/

#include <linux/acpi.h>
#include <linux/io.h>
#include <linux/ioport.h>
#include <linux/mm.h>
#include <linux/module.h>
#include <linux/platform_device.h>
#include <linux/pm.h>
Expand Down Expand Up @@ -309,6 +311,29 @@ static struct watchdog_ops wdat_wdt_ops = {
.set_timeout = wdat_wdt_set_timeout,
};

static void __iomem *wdat_wdt_map_mem(struct device *dev, struct resource *res)
{
resource_size_t size = resource_size(res);
void *addr;

/* Map memory region without reserving it if it falls inside ACPI NVS */
if (region_intersects(res->start, size, IORESOURCE_MEM,
IORES_DESC_ACPI_NV_STORAGE) == REGION_INTERSECTS) {
dev_warn(dev, "%pR is inside ACPI NVS, mapping without reservation\n",
res);

addr = devm_memremap(dev, res->start, size, MEMREMAP_WB);
if (IS_ERR(addr)) {
dev_err(dev, "failed to map resource %pR\n", res);
return IOMEM_ERR_PTR(PTR_ERR(addr));
}

return (void __iomem __force *)addr;
}

return devm_ioremap_resource(dev, res);
}

static int wdat_wdt_probe(struct platform_device *pdev)
{
struct device *dev = &pdev->dev;
Expand Down Expand Up @@ -362,7 +387,7 @@ static int wdat_wdt_probe(struct platform_device *pdev)

res = &pdev->resource[i];
if (resource_type(res) == IORESOURCE_MEM) {
reg = devm_ioremap_resource(dev, res);
reg = wdat_wdt_map_mem(dev, res);
if (IS_ERR(reg)) {
ret = PTR_ERR(reg);
goto out_put_table;
Expand Down