[PATCH V8 03/11] misc/pvpanic: add MMIO support

From: Peng Hao
Date: Tue Nov 06 2018 - 01:47:52 EST


On some architectures (e.g. arm64), it's preferable to use MMIO, since
this can be used standalone. Add MMIO support to the pvpanic driver.

Suggested-by: Andy Shevchenko <andy.shevchenko@xxxxxxxxx>
[Use acpi_dev_resource_memory API. - Andy]
Reviewed-by: Andy Shevchenko <andy.shevchenko@xxxxxxxxx>
Acked-by: Mark Rutland <mark.rutland@xxxxxxx>
Signed-off-by: Peng Hao <peng.hao2@xxxxxxxxxx>
---
drivers/misc/pvpanic.c | 15 ++++++++++-----
1 file changed, 10 insertions(+), 5 deletions(-)

diff --git a/drivers/misc/pvpanic.c b/drivers/misc/pvpanic.c
index 49c59e1..e923dac 100644
--- a/drivers/misc/pvpanic.c
+++ b/drivers/misc/pvpanic.c
@@ -26,6 +26,8 @@
#include <linux/types.h>
#include <linux/acpi.h>

+static void __iomem *base;
+
MODULE_AUTHOR("Hu Tao <hutao@xxxxxxxxxxxxxx>");
MODULE_DESCRIPTION("pvpanic device driver");
MODULE_LICENSE("GPL");
@@ -41,8 +43,6 @@

#define PVPANIC_PANICKED (1 << 0)

-static u16 port;
-
static struct acpi_driver pvpanic_driver = {
.name = "pvpanic",
.class = "QEMU",
@@ -57,7 +57,7 @@
static void
pvpanic_send_event(unsigned int event)
{
- outb(event, port);
+ iowrite8(event, base);
}

static int
@@ -80,7 +80,10 @@
struct resource r;

if (acpi_dev_resource_io(res, &r)) {
- port = r.start;
+ base = ioport_map(r.start, resource_size(&r));
+ return AE_OK;
+ } else if (acpi_dev_resource_memory(res, &r)) {
+ base = ioremap(r.start, resource_size(&r));
return AE_OK;
}

@@ -101,7 +104,7 @@ static int pvpanic_add(struct acpi_device *device)
acpi_walk_resources(device->handle, METHOD_NAME__CRS,
pvpanic_walk_resources, NULL);

- if (!port)
+ if (!base)
return -ENODEV;

atomic_notifier_chain_register(&panic_notifier_list,
@@ -115,6 +118,8 @@ static int pvpanic_remove(struct acpi_device *device)

atomic_notifier_chain_unregister(&panic_notifier_list,
&pvpanic_panic_nb);
+ iounmap(base);
+
return 0;
}

--
1.8.3.1