* [PATCH V4 1/2] vfio, platform: add support for ACPI during probe and reset
[not found] <1462136872-17590-1-git-send-email-okaya@codeaurora.org>
@ 2016-05-01 21:07 ` Sinan Kaya
2016-05-09 15:47 ` Eric Auger
2016-05-01 21:07 ` [PATCH V4 2/2] vfio, platform: make reset driver a requirement by default Sinan Kaya
1 sibling, 1 reply; 4+ messages in thread
From: Sinan Kaya @ 2016-05-01 21:07 UTC (permalink / raw)
To: kvm, timur, cov, jcm, eric.auger
Cc: shankerd, vikrams, marc.zyngier, mark.rutland, devicetree,
vinod.koul, agross, linux-arm-msm, linux-arm-kernel, Sinan Kaya,
Baptiste Reynal, Alex Williamson, linux-kernel
The code is using the compatible DT string to associate a reset driver with
the actual device itself. The compatible string does not exist on ACPI
based systems. HID is the unique identifier for a device driver instead.
When ACPI is enabled, the change will query the presence of _RST method
and will call it instead of querying an external reset driver.
Signed-off-by: Sinan Kaya <okaya@codeaurora.org>
---
drivers/vfio/platform/vfio_platform_common.c | 176 +++++++++++++++++++++-----
drivers/vfio/platform/vfio_platform_private.h | 7 +-
2 files changed, 147 insertions(+), 36 deletions(-)
diff --git a/drivers/vfio/platform/vfio_platform_common.c b/drivers/vfio/platform/vfio_platform_common.c
index e65b142..528ec04 100644
--- a/drivers/vfio/platform/vfio_platform_common.c
+++ b/drivers/vfio/platform/vfio_platform_common.c
@@ -13,6 +13,7 @@
*/
#include <linux/device.h>
+#include <linux/acpi.h>
#include <linux/iommu.h>
#include <linux/module.h>
#include <linux/mutex.h>
@@ -41,7 +42,7 @@ static vfio_platform_reset_fn_t vfio_platform_lookup_reset(const char *compat,
if (!strcmp(iter->compat, compat) &&
try_module_get(iter->owner)) {
*module = iter->owner;
- reset_fn = iter->reset;
+ reset_fn = iter->of_reset;
break;
}
}
@@ -49,20 +50,111 @@ static vfio_platform_reset_fn_t vfio_platform_lookup_reset(const char *compat,
return reset_fn;
}
-static void vfio_platform_get_reset(struct vfio_platform_device *vdev)
+
+#ifdef CONFIG_ACPI
+int vfio_platform_acpi_probe(struct vfio_platform_device *vdev,
+ struct device *dev)
{
- vdev->reset = vfio_platform_lookup_reset(vdev->compat,
- &vdev->reset_module);
- if (!vdev->reset) {
- request_module("vfio-reset:%s", vdev->compat);
- vdev->reset = vfio_platform_lookup_reset(vdev->compat,
- &vdev->reset_module);
+ struct acpi_device *adev = ACPI_COMPANION(dev);
+
+ if (acpi_disabled)
+ return -ENODEV;
+
+ if (!adev)
+ return -ENODEV;
+
+ vdev->acpihid = acpi_device_hid(adev);
+ if (!vdev->acpihid) {
+ pr_err("VFIO: cannot find ACPI HID for %s\n",
+ vdev->name);
+ return -ENODEV;
}
+ return 0;
+}
+
+static int vfio_platform_acpi_call_reset(struct vfio_platform_device *vdev)
+{
+ struct device *dev = vdev->device;
+ acpi_handle handle = ACPI_HANDLE(dev);
+ acpi_status acpi_ret;
+ unsigned long long val;
+
+ acpi_ret = acpi_evaluate_integer(handle, "_RST", NULL, &val);
+ if (ACPI_FAILURE(acpi_ret))
+ return -EINVAL;
+
+ return 0;
+}
+
+static int vfio_platform_acpi_has_reset(struct vfio_platform_device *vdev)
+{
+ struct device *dev = vdev->device;
+ acpi_handle handle = ACPI_HANDLE(dev);
+
+ if (acpi_has_method(handle, "_RST"))
+ return 0;
+
+ return -EINVAL;
+}
+#else
+int vfio_platform_acpi_probe(struct vfio_platform_device *vdev,
+ struct device *dev)
+{
+ return -EINVAL;
+}
+
+static int vfio_platform_acpi_call_reset(struct vfio_platform_device *vdev)
+{
+ return -EINVAL;
+}
+
+static int vfio_platform_acpi_has_reset(struct vfio_platform_device *vdev)
+{
+ return -EINVAL;
+}
+#endif
+
+static int vfio_platform_has_reset(struct vfio_platform_device *vdev)
+{
+ if (vdev->acpihid)
+ return vfio_platform_acpi_has_reset(vdev);
+
+ if (vdev->of_reset)
+ return 0;
+
+ return -EINVAL;
+}
+
+static int vfio_platform_get_reset(struct vfio_platform_device *vdev)
+{
+ int rc;
+
+ if (vdev->acpihid)
+ return vfio_platform_acpi_has_reset(vdev);
+
+ vdev->of_reset = vfio_platform_lookup_reset(vdev->compat,
+ &vdev->reset_module);
+ if (vdev->of_reset)
+ return 0;
+
+ rc = request_module("vfio-reset:%s", vdev->compat);
+ if (rc)
+ return rc;
+
+ vdev->of_reset = vfio_platform_lookup_reset(vdev->compat,
+ &vdev->reset_module);
+ if (vdev->of_reset)
+ return 0;
+
+ return -EINVAL;
}
static void vfio_platform_put_reset(struct vfio_platform_device *vdev)
{
- if (vdev->reset)
+ if (vdev->acpihid)
+ return;
+
+ if (vdev->of_reset)
module_put(vdev->reset_module);
}
@@ -134,6 +226,20 @@ static void vfio_platform_regions_cleanup(struct vfio_platform_device *vdev)
kfree(vdev->regions);
}
+static int vfio_platform_call_reset(struct vfio_platform_device *vdev)
+{
+ if (vdev->of_reset) {
+ dev_info(vdev->device, "reset\n");
+ vdev->of_reset(vdev);
+ return 0;
+ } else if (vdev->acpihid) {
+ return vfio_platform_acpi_call_reset(vdev);
+ }
+
+ dev_warn(vdev->device, "no reset function found!\n");
+ return -EINVAL;
+}
+
static void vfio_platform_release(void *device_data)
{
struct vfio_platform_device *vdev = device_data;
@@ -141,12 +247,7 @@ static void vfio_platform_release(void *device_data)
mutex_lock(&driver_lock);
if (!(--vdev->refcnt)) {
- if (vdev->reset) {
- dev_info(vdev->device, "reset\n");
- vdev->reset(vdev);
- } else {
- dev_warn(vdev->device, "no reset function found!\n");
- }
+ vfio_platform_call_reset(vdev);
vfio_platform_regions_cleanup(vdev);
vfio_platform_irq_cleanup(vdev);
}
@@ -175,12 +276,9 @@ static int vfio_platform_open(void *device_data)
if (ret)
goto err_irq;
- if (vdev->reset) {
- dev_info(vdev->device, "reset\n");
- vdev->reset(vdev);
- } else {
- dev_warn(vdev->device, "no reset function found!\n");
- }
+ ret = vfio_platform_call_reset(vdev);
+ if (ret)
+ goto err_irq;
}
vdev->refcnt++;
@@ -213,7 +311,7 @@ static long vfio_platform_ioctl(void *device_data,
if (info.argsz < minsz)
return -EINVAL;
- if (vdev->reset)
+ if (!vfio_platform_has_reset(vdev))
vdev->flags |= VFIO_DEVICE_FLAGS_RESET;
info.flags = vdev->flags;
info.num_regions = vdev->num_regions;
@@ -312,10 +410,7 @@ static long vfio_platform_ioctl(void *device_data,
return ret;
} else if (cmd == VFIO_DEVICE_RESET) {
- if (vdev->reset)
- return vdev->reset(vdev);
- else
- return -EINVAL;
+ return vfio_platform_call_reset(vdev);
}
return -ENOTTY;
@@ -544,6 +639,21 @@ static const struct vfio_device_ops vfio_platform_ops = {
.mmap = vfio_platform_mmap,
};
+int vfio_platform_of_probe(struct vfio_platform_device *vdev,
+ struct device *dev)
+{
+ int ret;
+
+ ret = device_property_read_string(dev, "compatible",
+ &vdev->compat);
+ if (ret) {
+ pr_err("VFIO: cannot retrieve compat for %s\n",
+ vdev->name);
+ return ret;
+ }
+ return 0;
+}
+
int vfio_platform_probe_common(struct vfio_platform_device *vdev,
struct device *dev)
{
@@ -553,14 +663,14 @@ int vfio_platform_probe_common(struct vfio_platform_device *vdev,
if (!vdev)
return -EINVAL;
- ret = device_property_read_string(dev, "compatible", &vdev->compat);
- if (ret) {
- pr_err("VFIO: cannot retrieve compat for %s\n", vdev->name);
- return -EINVAL;
- }
+ ret = vfio_platform_acpi_probe(vdev, dev);
+ if (ret)
+ ret = vfio_platform_of_probe(vdev, dev);
- vdev->device = dev;
+ if (ret)
+ return ret;
+ vdev->device = dev;
group = iommu_group_get(dev);
if (!group) {
pr_err("VFIO: No IOMMU group for device %s\n", vdev->name);
@@ -611,7 +721,7 @@ void vfio_platform_unregister_reset(const char *compat,
mutex_lock(&driver_lock);
list_for_each_entry_safe(iter, temp, &reset_list, link) {
- if (!strcmp(iter->compat, compat) && (iter->reset == fn)) {
+ if (!strcmp(iter->compat, compat) && (iter->of_reset == fn)) {
list_del(&iter->link);
break;
}
diff --git a/drivers/vfio/platform/vfio_platform_private.h b/drivers/vfio/platform/vfio_platform_private.h
index 42816dd..ba9e4f8 100644
--- a/drivers/vfio/platform/vfio_platform_private.h
+++ b/drivers/vfio/platform/vfio_platform_private.h
@@ -58,6 +58,7 @@ struct vfio_platform_device {
struct mutex igate;
struct module *parent_module;
const char *compat;
+ const char *acpihid;
struct module *reset_module;
struct device *device;
@@ -71,7 +72,7 @@ struct vfio_platform_device {
struct resource*
(*get_resource)(struct vfio_platform_device *vdev, int i);
int (*get_irq)(struct vfio_platform_device *vdev, int i);
- int (*reset)(struct vfio_platform_device *vdev);
+ int (*of_reset)(struct vfio_platform_device *vdev);
};
typedef int (*vfio_platform_reset_fn_t)(struct vfio_platform_device *vdev);
@@ -80,7 +81,7 @@ struct vfio_platform_reset_node {
struct list_head link;
char *compat;
struct module *owner;
- vfio_platform_reset_fn_t reset;
+ vfio_platform_reset_fn_t of_reset;
};
extern int vfio_platform_probe_common(struct vfio_platform_device *vdev,
@@ -103,7 +104,7 @@ extern void vfio_platform_unregister_reset(const char *compat,
static struct vfio_platform_reset_node __reset ## _node = { \
.owner = THIS_MODULE, \
.compat = __compat, \
- .reset = __reset, \
+ .of_reset = __reset, \
}; \
__vfio_platform_register_reset(&__reset ## _node)
--
1.8.2.1
^ permalink raw reply related [flat|nested] 4+ messages in thread
* [PATCH V4 2/2] vfio, platform: make reset driver a requirement by default
[not found] <1462136872-17590-1-git-send-email-okaya@codeaurora.org>
2016-05-01 21:07 ` [PATCH V4 1/2] vfio, platform: add support for ACPI during probe and reset Sinan Kaya
@ 2016-05-01 21:07 ` Sinan Kaya
1 sibling, 0 replies; 4+ messages in thread
From: Sinan Kaya @ 2016-05-01 21:07 UTC (permalink / raw)
To: kvm, timur, cov, jcm, eric.auger
Cc: shankerd, vikrams, marc.zyngier, mark.rutland, devicetree,
vinod.koul, agross, linux-arm-msm, linux-arm-kernel, Sinan Kaya,
Baptiste Reynal, Alex Williamson, linux-kernel
The code was allowing platform devices to be used without a supporting VFIO
reset driver. The hardware can be left in some inconsistent state after a
guest machine abort.
The reset driver will put the hardware back to safe state and disable
interrupts before returning the control back to the host machine.
Signed-off-by: Sinan Kaya <okaya@codeaurora.org>
---
drivers/vfio/platform/vfio_amba.c | 5 +++++
drivers/vfio/platform/vfio_platform.c | 5 +++++
drivers/vfio/platform/vfio_platform_common.c | 8 +++++++-
drivers/vfio/platform/vfio_platform_private.h | 1 +
4 files changed, 18 insertions(+), 1 deletion(-)
diff --git a/drivers/vfio/platform/vfio_amba.c b/drivers/vfio/platform/vfio_amba.c
index a66479b..7585902 100644
--- a/drivers/vfio/platform/vfio_amba.c
+++ b/drivers/vfio/platform/vfio_amba.c
@@ -23,6 +23,10 @@
#define DRIVER_AUTHOR "Antonios Motakis <a.motakis@virtualopensystems.com>"
#define DRIVER_DESC "VFIO for AMBA devices - User Level meta-driver"
+static bool reset_required = true;
+module_param(reset_required, bool, 0644);
+MODULE_PARM_DESC(reset_required, "override reset requirement (default: 1)");
+
/* probing devices from the AMBA bus */
static struct resource *get_amba_resource(struct vfio_platform_device *vdev,
@@ -68,6 +72,7 @@ static int vfio_amba_probe(struct amba_device *adev, const struct amba_id *id)
vdev->get_resource = get_amba_resource;
vdev->get_irq = get_amba_irq;
vdev->parent_module = THIS_MODULE;
+ vdev->reset_required = reset_required;
ret = vfio_platform_probe_common(vdev, &adev->dev);
if (ret) {
diff --git a/drivers/vfio/platform/vfio_platform.c b/drivers/vfio/platform/vfio_platform.c
index b1cc3a7..ef89146 100644
--- a/drivers/vfio/platform/vfio_platform.c
+++ b/drivers/vfio/platform/vfio_platform.c
@@ -23,6 +23,10 @@
#define DRIVER_AUTHOR "Antonios Motakis <a.motakis@virtualopensystems.com>"
#define DRIVER_DESC "VFIO for platform devices - User Level meta-driver"
+static bool reset_required = true;
+module_param(reset_required, bool, 0644);
+MODULE_PARM_DESC(reset_required, "override reset requirement (default: 1)");
+
/* probing devices from the linux platform bus */
static struct resource *get_platform_resource(struct vfio_platform_device *vdev,
@@ -66,6 +70,7 @@ static int vfio_platform_probe(struct platform_device *pdev)
vdev->get_resource = get_platform_resource;
vdev->get_irq = get_platform_irq;
vdev->parent_module = THIS_MODULE;
+ vdev->reset_required = reset_required;
ret = vfio_platform_probe_common(vdev, &pdev->dev);
if (ret)
diff --git a/drivers/vfio/platform/vfio_platform_common.c b/drivers/vfio/platform/vfio_platform_common.c
index 528ec04..b342538 100644
--- a/drivers/vfio/platform/vfio_platform_common.c
+++ b/drivers/vfio/platform/vfio_platform_common.c
@@ -683,7 +683,13 @@ int vfio_platform_probe_common(struct vfio_platform_device *vdev,
return ret;
}
- vfio_platform_get_reset(vdev);
+ ret = vfio_platform_get_reset(vdev);
+ if (ret && vdev->reset_required) {
+ pr_err("vfio: no reset function found for device %s\n",
+ vdev->name);
+ iommu_group_put(group);
+ return ret;
+ }
mutex_init(&vdev->igate);
diff --git a/drivers/vfio/platform/vfio_platform_private.h b/drivers/vfio/platform/vfio_platform_private.h
index ba9e4f8..68fbc00 100644
--- a/drivers/vfio/platform/vfio_platform_private.h
+++ b/drivers/vfio/platform/vfio_platform_private.h
@@ -50,6 +50,7 @@ struct vfio_platform_region {
};
struct vfio_platform_device {
+ bool reset_required;
struct vfio_platform_region *regions;
u32 num_regions;
struct vfio_platform_irq *irqs;
--
1.8.2.1
^ permalink raw reply related [flat|nested] 4+ messages in thread
* Re: [PATCH V4 1/2] vfio, platform: add support for ACPI during probe and reset
2016-05-01 21:07 ` [PATCH V4 1/2] vfio, platform: add support for ACPI during probe and reset Sinan Kaya
@ 2016-05-09 15:47 ` Eric Auger
2016-05-09 19:45 ` Sinan Kaya
0 siblings, 1 reply; 4+ messages in thread
From: Eric Auger @ 2016-05-09 15:47 UTC (permalink / raw)
To: Sinan Kaya, kvm, timur, cov, jcm
Cc: shankerd, vikrams, marc.zyngier, mark.rutland, devicetree,
vinod.koul, agross, linux-arm-msm, linux-arm-kernel,
Baptiste Reynal, Alex Williamson, linux-kernel
Hi Sinan,
On 05/01/2016 11:07 PM, Sinan Kaya wrote:
> The code is using the compatible DT string to associate a reset driver with
> the actual device itself. The compatible string does not exist on ACPI
> based systems. HID is the unique identifier for a device driver instead.
>
> When ACPI is enabled, the change will query the presence of _RST method
> and will call it instead of querying an external reset driver.
>
> Signed-off-by: Sinan Kaya <okaya@codeaurora.org>
> ---
> drivers/vfio/platform/vfio_platform_common.c | 176 +++++++++++++++++++++-----
> drivers/vfio/platform/vfio_platform_private.h | 7 +-
> 2 files changed, 147 insertions(+), 36 deletions(-)
>
> diff --git a/drivers/vfio/platform/vfio_platform_common.c b/drivers/vfio/platform/vfio_platform_common.c
> index e65b142..528ec04 100644
> --- a/drivers/vfio/platform/vfio_platform_common.c
> +++ b/drivers/vfio/platform/vfio_platform_common.c
> @@ -13,6 +13,7 @@
> */
>
> #include <linux/device.h>
> +#include <linux/acpi.h>
> #include <linux/iommu.h>
> #include <linux/module.h>
> #include <linux/mutex.h>
> @@ -41,7 +42,7 @@ static vfio_platform_reset_fn_t vfio_platform_lookup_reset(const char *compat,
> if (!strcmp(iter->compat, compat) &&
> try_module_get(iter->owner)) {
> *module = iter->owner;
> - reset_fn = iter->reset;
> + reset_fn = iter->of_reset;
> break;
> }
> }
> @@ -49,20 +50,111 @@ static vfio_platform_reset_fn_t vfio_platform_lookup_reset(const char *compat,
> return reset_fn;
> }
>
> -static void vfio_platform_get_reset(struct vfio_platform_device *vdev)
> +
> +#ifdef CONFIG_ACPI
> +int vfio_platform_acpi_probe(struct vfio_platform_device *vdev,
> + struct device *dev)
> {
> - vdev->reset = vfio_platform_lookup_reset(vdev->compat,
> - &vdev->reset_module);
> - if (!vdev->reset) {
> - request_module("vfio-reset:%s", vdev->compat);
> - vdev->reset = vfio_platform_lookup_reset(vdev->compat,
> - &vdev->reset_module);
> + struct acpi_device *adev = ACPI_COMPANION(dev);
> +
> + if (acpi_disabled)
> + return -ENODEV;
> +
> + if (!adev)
> + return -ENODEV;
> +
> + vdev->acpihid = acpi_device_hid(adev);
> + if (!vdev->acpihid) {
> + pr_err("VFIO: cannot find ACPI HID for %s\n",
> + vdev->name);
> + return -ENODEV;
> }
> + return 0;
> +}
> +
> +static int vfio_platform_acpi_call_reset(struct vfio_platform_device *vdev)
> +{
> + struct device *dev = vdev->device;
> + acpi_handle handle = ACPI_HANDLE(dev);
> + acpi_status acpi_ret;
> + unsigned long long val;
> +
> + acpi_ret = acpi_evaluate_integer(handle, "_RST", NULL, &val);
> + if (ACPI_FAILURE(acpi_ret))
> + return -EINVAL;
> +
> + return 0;
> +}
> +
> +static int vfio_platform_acpi_has_reset(struct vfio_platform_device *vdev)
> +{
> + struct device *dev = vdev->device;
> + acpi_handle handle = ACPI_HANDLE(dev);
> +
> + if (acpi_has_method(handle, "_RST"))
> + return 0;
Can't you directly return acpi_has_method(handle, "_RST"), hence return
a boolean?
> +
> + return -EINVAL;
> +}
> +#else
> +int vfio_platform_acpi_probe(struct vfio_platform_device *vdev,
> + struct device *dev)
> +{
> + return -EINVAL;
> +}
> +
> +static int vfio_platform_acpi_call_reset(struct vfio_platform_device *vdev)
> +{
> + return -EINVAL;
> +}
> +
> +static int vfio_platform_acpi_has_reset(struct vfio_platform_device *vdev)
> +{
> + return -EINVAL;
> +}
> +#endif
> +
> +static int vfio_platform_has_reset(struct vfio_platform_device *vdev)
> +{
return a boolean?
> + if (vdev->acpihid)
> + return vfio_platform_acpi_has_reset(vdev);
> +
> + if (vdev->of_reset)
> + return 0;
> +
> + return -EINVAL;
> +}
> +
> +static int vfio_platform_get_reset(struct vfio_platform_device *vdev)
> +{
> + int rc;
> +
> + if (vdev->acpihid)
> + return vfio_platform_acpi_has_reset(vdev);
> +
> + vdev->of_reset = vfio_platform_lookup_reset(vdev->compat,
> + &vdev->reset_module);
> + if (vdev->of_reset)
> + return 0;
> +
> + rc = request_module("vfio-reset:%s", vdev->compat);
> + if (rc)
> + return rc;
> +
> + vdev->of_reset = vfio_platform_lookup_reset(vdev->compat,
> + &vdev->reset_module);
> + if (vdev->of_reset)
> + return 0;
> +
> + return -EINVAL;
> }
>
> static void vfio_platform_put_reset(struct vfio_platform_device *vdev)
> {
> - if (vdev->reset)
> + if (vdev->acpihid)
> + return;
> +
> + if (vdev->of_reset)
> module_put(vdev->reset_module);
> }
>
> @@ -134,6 +226,20 @@ static void vfio_platform_regions_cleanup(struct vfio_platform_device *vdev)
> kfree(vdev->regions);
> }
>
> +static int vfio_platform_call_reset(struct vfio_platform_device *vdev)
> +{
> + if (vdev->of_reset) {
> + dev_info(vdev->device, "reset\n");
> + vdev->of_reset(vdev);
return vdev->of_reset(vdev) to align with acpi reset behavior.
> + return 0;
> + } else if (vdev->acpihid) {
> + return vfio_platform_acpi_call_reset(vdev);
I think it would make sense to have the same dev_info traces for dt and
acpi.
> + }
> +
> + dev_warn(vdev->device, "no reset function found!\n");
> + return -EINVAL;
> +}
> +
> static void vfio_platform_release(void *device_data)
> {
> struct vfio_platform_device *vdev = device_data;
> @@ -141,12 +247,7 @@ static void vfio_platform_release(void *device_data)
> mutex_lock(&driver_lock);
>
> if (!(--vdev->refcnt)) {
> - if (vdev->reset) {
> - dev_info(vdev->device, "reset\n");
> - vdev->reset(vdev);
> - } else {
> - dev_warn(vdev->device, "no reset function found!\n");
> - }
> + vfio_platform_call_reset(vdev);
> vfio_platform_regions_cleanup(vdev);
> vfio_platform_irq_cleanup(vdev);
> }
> @@ -175,12 +276,9 @@ static int vfio_platform_open(void *device_data)
> if (ret)
> goto err_irq;
>
> - if (vdev->reset) {
> - dev_info(vdev->device, "reset\n");
> - vdev->reset(vdev);
> - } else {
> - dev_warn(vdev->device, "no reset function found!\n");
> - }
> + ret = vfio_platform_call_reset(vdev);
> + if (ret)
> + goto err_irq;
This change should be in next patch since if you fail finding a reset
function, you clean things up, mandating a reset function to exist.
Also in case the reset function fails you change the behavior which is
not detailed in the commit msg.
> }
>
> vdev->refcnt++;
> @@ -213,7 +311,7 @@ static long vfio_platform_ioctl(void *device_data,
> if (info.argsz < minsz)
> return -EINVAL;
>
> - if (vdev->reset)
> + if (!vfio_platform_has_reset(vdev))
> vdev->flags |= VFIO_DEVICE_FLAGS_RESET;
> info.flags = vdev->flags;
> info.num_regions = vdev->num_regions;
> @@ -312,10 +410,7 @@ static long vfio_platform_ioctl(void *device_data,
> return ret;
>
> } else if (cmd == VFIO_DEVICE_RESET) {
> - if (vdev->reset)
> - return vdev->reset(vdev);
> - else
> - return -EINVAL;
> + return vfio_platform_call_reset(vdev);
Here you also change the behavior: before, in case the dt reset failed
we returned an error. Now we return 0.
To me this patch would deserve to be split into 2 parts: ACPI probing
without reset and then ACPI reset. In case you change the behavior of
existing dt reset, please put that in a separate patch.
Best Regards
Eric
> }
>
> return -ENOTTY;
> @@ -544,6 +639,21 @@ static const struct vfio_device_ops vfio_platform_ops = {
> .mmap = vfio_platform_mmap,
> };
>
> +int vfio_platform_of_probe(struct vfio_platform_device *vdev,
> + struct device *dev)
> +{
> + int ret;
> +
> + ret = device_property_read_string(dev, "compatible",
> + &vdev->compat);
> + if (ret) {
> + pr_err("VFIO: cannot retrieve compat for %s\n",
> + vdev->name);
> + return ret;
> + }
> + return 0;
> +}
> +
> int vfio_platform_probe_common(struct vfio_platform_device *vdev,
> struct device *dev)
> {
> @@ -553,14 +663,14 @@ int vfio_platform_probe_common(struct vfio_platform_device *vdev,
> if (!vdev)
> return -EINVAL;
>
> - ret = device_property_read_string(dev, "compatible", &vdev->compat);
> - if (ret) {
> - pr_err("VFIO: cannot retrieve compat for %s\n", vdev->name);
> - return -EINVAL;
> - }
> + ret = vfio_platform_acpi_probe(vdev, dev);
> + if (ret)
> + ret = vfio_platform_of_probe(vdev, dev);
>
> - vdev->device = dev;
> + if (ret)
> + return ret;
>
> + vdev->device = dev;
> group = iommu_group_get(dev);
> if (!group) {
> pr_err("VFIO: No IOMMU group for device %s\n", vdev->name);
> @@ -611,7 +721,7 @@ void vfio_platform_unregister_reset(const char *compat,
>
> mutex_lock(&driver_lock);
> list_for_each_entry_safe(iter, temp, &reset_list, link) {
> - if (!strcmp(iter->compat, compat) && (iter->reset == fn)) {
> + if (!strcmp(iter->compat, compat) && (iter->of_reset == fn)) {
> list_del(&iter->link);
> break;
> }
> diff --git a/drivers/vfio/platform/vfio_platform_private.h b/drivers/vfio/platform/vfio_platform_private.h
> index 42816dd..ba9e4f8 100644
> --- a/drivers/vfio/platform/vfio_platform_private.h
> +++ b/drivers/vfio/platform/vfio_platform_private.h
> @@ -58,6 +58,7 @@ struct vfio_platform_device {
> struct mutex igate;
> struct module *parent_module;
> const char *compat;
> + const char *acpihid;
> struct module *reset_module;
> struct device *device;
>
> @@ -71,7 +72,7 @@ struct vfio_platform_device {
> struct resource*
> (*get_resource)(struct vfio_platform_device *vdev, int i);
> int (*get_irq)(struct vfio_platform_device *vdev, int i);
> - int (*reset)(struct vfio_platform_device *vdev);
> + int (*of_reset)(struct vfio_platform_device *vdev);
> };
>
> typedef int (*vfio_platform_reset_fn_t)(struct vfio_platform_device *vdev);
> @@ -80,7 +81,7 @@ struct vfio_platform_reset_node {
> struct list_head link;
> char *compat;
> struct module *owner;
> - vfio_platform_reset_fn_t reset;
> + vfio_platform_reset_fn_t of_reset;
> };
>
> extern int vfio_platform_probe_common(struct vfio_platform_device *vdev,
> @@ -103,7 +104,7 @@ extern void vfio_platform_unregister_reset(const char *compat,
> static struct vfio_platform_reset_node __reset ## _node = { \
> .owner = THIS_MODULE, \
> .compat = __compat, \
> - .reset = __reset, \
> + .of_reset = __reset, \
> }; \
> __vfio_platform_register_reset(&__reset ## _node)
>
>
^ permalink raw reply [flat|nested] 4+ messages in thread
* Re: [PATCH V4 1/2] vfio, platform: add support for ACPI during probe and reset
2016-05-09 15:47 ` Eric Auger
@ 2016-05-09 19:45 ` Sinan Kaya
0 siblings, 0 replies; 4+ messages in thread
From: Sinan Kaya @ 2016-05-09 19:45 UTC (permalink / raw)
To: Eric Auger, kvm, timur, cov, jcm
Cc: shankerd, vikrams, marc.zyngier, mark.rutland, devicetree,
vinod.koul, agross, linux-arm-msm, linux-arm-kernel,
Baptiste Reynal, Alex Williamson, linux-kernel
On 5/9/2016 11:47 AM, Eric Auger wrote:
> Hi Sinan,
> On 05/01/2016 11:07 PM, Sinan Kaya wrote:
>> The code is using the compatible DT string to associate a reset driver with
>> the actual device itself. The compatible string does not exist on ACPI
>> based systems. HID is the unique identifier for a device driver instead.
>>
>> When ACPI is enabled, the change will query the presence of _RST method
>> and will call it instead of querying an external reset driver.
>>
>> Signed-off-by: Sinan Kaya <okaya@codeaurora.org>
>> ---
>> drivers/vfio/platform/vfio_platform_common.c | 176 +++++++++++++++++++++-----
>> drivers/vfio/platform/vfio_platform_private.h | 7 +-
>> 2 files changed, 147 insertions(+), 36 deletions(-)
>>
>> diff --git a/drivers/vfio/platform/vfio_platform_common.c b/drivers/vfio/platform/vfio_platform_common.c
>> index e65b142..528ec04 100644
>> --- a/drivers/vfio/platform/vfio_platform_common.c
>> +++ b/drivers/vfio/platform/vfio_platform_common.c
>> @@ -13,6 +13,7 @@
>> */
>>
>> #include <linux/device.h>
>> +#include <linux/acpi.h>
>> #include <linux/iommu.h>
>> #include <linux/module.h>
>> #include <linux/mutex.h>
>> @@ -41,7 +42,7 @@ static vfio_platform_reset_fn_t vfio_platform_lookup_reset(const char *compat,
>> if (!strcmp(iter->compat, compat) &&
>> try_module_get(iter->owner)) {
>> *module = iter->owner;
>> - reset_fn = iter->reset;
>> + reset_fn = iter->of_reset;
>> break;
>> }
>> }
>> @@ -49,20 +50,111 @@ static vfio_platform_reset_fn_t vfio_platform_lookup_reset(const char *compat,
>> return reset_fn;
>> }
>>
>> -static void vfio_platform_get_reset(struct vfio_platform_device *vdev)
>> +
>> +#ifdef CONFIG_ACPI
>> +int vfio_platform_acpi_probe(struct vfio_platform_device *vdev,
>> + struct device *dev)
>> {
>> - vdev->reset = vfio_platform_lookup_reset(vdev->compat,
>> - &vdev->reset_module);
>> - if (!vdev->reset) {
>> - request_module("vfio-reset:%s", vdev->compat);
>> - vdev->reset = vfio_platform_lookup_reset(vdev->compat,
>> - &vdev->reset_module);
>> + struct acpi_device *adev = ACPI_COMPANION(dev);
>> +
>> + if (acpi_disabled)
>> + return -ENODEV;
>> +
>> + if (!adev)
>> + return -ENODEV;
>> +
>> + vdev->acpihid = acpi_device_hid(adev);
>> + if (!vdev->acpihid) {
>> + pr_err("VFIO: cannot find ACPI HID for %s\n",
>> + vdev->name);
>> + return -ENODEV;
>> }
>> + return 0;
>> +}
>> +
>> +static int vfio_platform_acpi_call_reset(struct vfio_platform_device *vdev)
>> +{
>> + struct device *dev = vdev->device;
>> + acpi_handle handle = ACPI_HANDLE(dev);
>> + acpi_status acpi_ret;
>> + unsigned long long val;
>> +
>> + acpi_ret = acpi_evaluate_integer(handle, "_RST", NULL, &val);
>> + if (ACPI_FAILURE(acpi_ret))
>> + return -EINVAL;
>> +
>> + return 0;
>> +}
>> +
>> +static int vfio_platform_acpi_has_reset(struct vfio_platform_device *vdev)
>> +{
>> + struct device *dev = vdev->device;
>> + acpi_handle handle = ACPI_HANDLE(dev);
>> +
>> + if (acpi_has_method(handle, "_RST"))
>> + return 0;
> Can't you directly return acpi_has_method(handle, "_RST"), hence return
> a boolean?
Makes sense. I'll do that on the next post.
>> +
>> + return -EINVAL;
>> +}
>> +#else
>> +int vfio_platform_acpi_probe(struct vfio_platform_device *vdev,
>> + struct device *dev)
>> +{
>> + return -EINVAL;
>> +}
>> +
>> +static int vfio_platform_acpi_call_reset(struct vfio_platform_device *vdev)
>> +{
>> + return -EINVAL;
>> +}
>> +
>> +static int vfio_platform_acpi_has_reset(struct vfio_platform_device *vdev)
>> +{
>> + return -EINVAL;
>> +}
>> +#endif
>> +
>> +static int vfio_platform_has_reset(struct vfio_platform_device *vdev)
>> +{
> return a boolean?
OK
>> + if (vdev->acpihid)
>> + return vfio_platform_acpi_has_reset(vdev);
>> +
>> + if (vdev->of_reset)
>> + return 0;
>> +
>> + return -EINVAL;
>> +}
>> +
>> +static int vfio_platform_get_reset(struct vfio_platform_device *vdev)
>> +{
>> + int rc;
>> +
>> + if (vdev->acpihid)
>> + return vfio_platform_acpi_has_reset(vdev);
>> +
>> + vdev->of_reset = vfio_platform_lookup_reset(vdev->compat,
>> + &vdev->reset_module);
>> + if (vdev->of_reset)
>> + return 0;
>> +
>> + rc = request_module("vfio-reset:%s", vdev->compat);
>> + if (rc)
>> + return rc;
>> +
>> + vdev->of_reset = vfio_platform_lookup_reset(vdev->compat,
>> + &vdev->reset_module);
>> + if (vdev->of_reset)
>> + return 0;
>> +
>> + return -EINVAL;
>> }
>>
>> static void vfio_platform_put_reset(struct vfio_platform_device *vdev)
>> {
>> - if (vdev->reset)
>> + if (vdev->acpihid)
>> + return;
>> +
>> + if (vdev->of_reset)
>> module_put(vdev->reset_module);
>> }
>>
>> @@ -134,6 +226,20 @@ static void vfio_platform_regions_cleanup(struct vfio_platform_device *vdev)
>> kfree(vdev->regions);
>> }
>>
>> +static int vfio_platform_call_reset(struct vfio_platform_device *vdev)
>> +{
>> + if (vdev->of_reset) {
>> + dev_info(vdev->device, "reset\n");
>> + vdev->of_reset(vdev);
> return vdev->of_reset(vdev) to align with acpi reset behavior.
OK. I didn't realize it was returning a value.
>> + return 0;
>> + } else if (vdev->acpihid) {
>> + return vfio_platform_acpi_call_reset(vdev);
> I think it would make sense to have the same dev_info traces for dt and
> acpi.
>> + }
>> +
>> + dev_warn(vdev->device, "no reset function found!\n");
>> + return -EINVAL;
>> +}
>> +
>> static void vfio_platform_release(void *device_data)
>> {
>> struct vfio_platform_device *vdev = device_data;
>> @@ -141,12 +247,7 @@ static void vfio_platform_release(void *device_data)
>> mutex_lock(&driver_lock);
>>
>> if (!(--vdev->refcnt)) {
>> - if (vdev->reset) {
>> - dev_info(vdev->device, "reset\n");
>> - vdev->reset(vdev);
>> - } else {
>> - dev_warn(vdev->device, "no reset function found!\n");
>> - }
>> + vfio_platform_call_reset(vdev);
>> vfio_platform_regions_cleanup(vdev);
>> vfio_platform_irq_cleanup(vdev);
>> }
>> @@ -175,12 +276,9 @@ static int vfio_platform_open(void *device_data)
>> if (ret)
>> goto err_irq;
>>
>> - if (vdev->reset) {
>> - dev_info(vdev->device, "reset\n");
>> - vdev->reset(vdev);
>> - } else {
>> - dev_warn(vdev->device, "no reset function found!\n");
>> - }
>> + ret = vfio_platform_call_reset(vdev);
>> + if (ret)
>> + goto err_irq;
> This change should be in next patch since if you fail finding a reset
> function, you clean things up, mandating a reset function to exist.
>
> Also in case the reset function fails you change the behavior which is
> not detailed in the commit msg.
I admitted this on another patch. Yes, I'll fix this.
>> }
>>
>> vdev->refcnt++;
>> @@ -213,7 +311,7 @@ static long vfio_platform_ioctl(void *device_data,
>> if (info.argsz < minsz)
>> return -EINVAL;
>>
>> - if (vdev->reset)
>> + if (!vfio_platform_has_reset(vdev))
>> vdev->flags |= VFIO_DEVICE_FLAGS_RESET;
>> info.flags = vdev->flags;
>> info.num_regions = vdev->num_regions;
>> @@ -312,10 +410,7 @@ static long vfio_platform_ioctl(void *device_data,
>> return ret;
>>
>> } else if (cmd == VFIO_DEVICE_RESET) {
>> - if (vdev->reset)
>> - return vdev->reset(vdev);
>> - else
>> - return -EINVAL;
>> + return vfio_platform_call_reset(vdev);
> Here you also change the behavior: before, in case the dt reset failed
> we returned an error. Now we return 0.
Yes, I'll fix it.
>
> To me this patch would deserve to be split into 2 parts: ACPI probing
> without reset and then ACPI reset. In case you change the behavior of
> existing dt reset, please put that in a separate patch.
Sure, I'll move vfio_platform_probe_common changes to a seperate patch.
I'll try to break it as much as I can before the post.
>
> Best Regards
>
> Eric
>> }
>>
>> return -ENOTTY;
>> @@ -544,6 +639,21 @@ static const struct vfio_device_ops vfio_platform_ops = {
>> .mmap = vfio_platform_mmap,
>> };
>>
>> +int vfio_platform_of_probe(struct vfio_platform_device *vdev,
>> + struct device *dev)
>> +{
>> + int ret;
>> +
>> + ret = device_property_read_string(dev, "compatible",
>> + &vdev->compat);
>> + if (ret) {
>> + pr_err("VFIO: cannot retrieve compat for %s\n",
>> + vdev->name);
>> + return ret;
>> + }
>> + return 0;
>> +}
>> +
>> int vfio_platform_probe_common(struct vfio_platform_device *vdev,
>> struct device *dev)
>> {
>> @@ -553,14 +663,14 @@ int vfio_platform_probe_common(struct vfio_platform_device *vdev,
>> if (!vdev)
>> return -EINVAL;
>>
>> - ret = device_property_read_string(dev, "compatible", &vdev->compat);
>> - if (ret) {
>> - pr_err("VFIO: cannot retrieve compat for %s\n", vdev->name);
>> - return -EINVAL;
>> - }
>> + ret = vfio_platform_acpi_probe(vdev, dev);
>> + if (ret)
>> + ret = vfio_platform_of_probe(vdev, dev);
>>
>> - vdev->device = dev;
>> + if (ret)
>> + return ret;
>>
>> + vdev->device = dev;
>> group = iommu_group_get(dev);
>> if (!group) {
>> pr_err("VFIO: No IOMMU group for device %s\n", vdev->name);
>> @@ -611,7 +721,7 @@ void vfio_platform_unregister_reset(const char *compat,
>>
>> mutex_lock(&driver_lock);
>> list_for_each_entry_safe(iter, temp, &reset_list, link) {
>> - if (!strcmp(iter->compat, compat) && (iter->reset == fn)) {
>> + if (!strcmp(iter->compat, compat) && (iter->of_reset == fn)) {
>> list_del(&iter->link);
>> break;
>> }
>> diff --git a/drivers/vfio/platform/vfio_platform_private.h b/drivers/vfio/platform/vfio_platform_private.h
>> index 42816dd..ba9e4f8 100644
>> --- a/drivers/vfio/platform/vfio_platform_private.h
>> +++ b/drivers/vfio/platform/vfio_platform_private.h
>> @@ -58,6 +58,7 @@ struct vfio_platform_device {
>> struct mutex igate;
>> struct module *parent_module;
>> const char *compat;
>> + const char *acpihid;
>> struct module *reset_module;
>> struct device *device;
>>
>> @@ -71,7 +72,7 @@ struct vfio_platform_device {
>> struct resource*
>> (*get_resource)(struct vfio_platform_device *vdev, int i);
>> int (*get_irq)(struct vfio_platform_device *vdev, int i);
>> - int (*reset)(struct vfio_platform_device *vdev);
>> + int (*of_reset)(struct vfio_platform_device *vdev);
>> };
>>
>> typedef int (*vfio_platform_reset_fn_t)(struct vfio_platform_device *vdev);
>> @@ -80,7 +81,7 @@ struct vfio_platform_reset_node {
>> struct list_head link;
>> char *compat;
>> struct module *owner;
>> - vfio_platform_reset_fn_t reset;
>> + vfio_platform_reset_fn_t of_reset;
>> };
>>
>> extern int vfio_platform_probe_common(struct vfio_platform_device *vdev,
>> @@ -103,7 +104,7 @@ extern void vfio_platform_unregister_reset(const char *compat,
>> static struct vfio_platform_reset_node __reset ## _node = { \
>> .owner = THIS_MODULE, \
>> .compat = __compat, \
>> - .reset = __reset, \
>> + .of_reset = __reset, \
>> }; \
>> __vfio_platform_register_reset(&__reset ## _node)
>>
>>
>
--
Sinan Kaya
Qualcomm Technologies, Inc. on behalf of Qualcomm Innovation Center, Inc.
Qualcomm Innovation Center, Inc. is a member of Code Aurora Forum, a Linux Foundation Collaborative Project
^ permalink raw reply [flat|nested] 4+ messages in thread
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[not found] <1462136872-17590-1-git-send-email-okaya@codeaurora.org>
2016-05-01 21:07 ` [PATCH V4 1/2] vfio, platform: add support for ACPI during probe and reset Sinan Kaya
2016-05-09 15:47 ` Eric Auger
2016-05-09 19:45 ` Sinan Kaya
2016-05-01 21:07 ` [PATCH V4 2/2] vfio, platform: make reset driver a requirement by default Sinan Kaya
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