[PATCH V4 3/5] misc/pvpanic: add MMIO support

From: Peng Hao
Date: Wed Oct 31 2018 - 01:27:22 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.

Signed-off-by: Peng Hao <peng.hao2@xxxxxxxxxx>
---
drivers/misc/pvpanic.c | 20 ++++++++++++++++----
1 file changed, 16 insertions(+), 4 deletions(-)

diff --git a/drivers/misc/pvpanic.c b/drivers/misc/pvpanic.c
index 9450376..d0e28b2 100644
--- a/drivers/misc/pvpanic.c
+++ b/drivers/misc/pvpanic.c
@@ -28,7 +28,7 @@

#define PVPANIC_PANICKED (1 << 0)

-static u16 port;
+static void __iomem *base;

static struct acpi_driver pvpanic_driver = {
.name = "pvpanic",
@@ -44,7 +44,7 @@
static void
pvpanic_send_event(unsigned int event)
{
- outb(event, port);
+ iowrite8(event, base);
}

static int
@@ -64,12 +64,21 @@
static acpi_status
pvpanic_walk_resources(struct acpi_resource *res, void *context)
{
+ struct resource r;
+
switch (res->type) {
case ACPI_RESOURCE_TYPE_END_TAG:
return AE_OK;

case ACPI_RESOURCE_TYPE_IO:
- port = res->data.io.minimum;
+ if (acpi_dev_resource_io(res, &r))
+ base = (void __iomem *) ioport_map(r.start,
+ r.end - r.start + 1);
+ return AE_OK;
+
+ case ACPI_RESOURCE_TYPE_FIXED_MEMORY32:
+ if (acpi_dev_resource_memory(res, &r))
+ base = ioremap(r.start, r.end - r.start + 1);
return AE_OK;

default:
@@ -91,7 +100,7 @@ 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,
@@ -105,6 +114,9 @@ static int pvpanic_remove(struct acpi_device *device)

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

--
1.8.3.1