Some platforms expose PMT discovery via ACPI instead of PCI BARs. Add a
generic discovery source flag and carry ACPI discovery entries alongside
the existing PCI resource path so PMT clients can consume either.
Changes:
- Add enum intel_vsec_disc_source { _PCI, _ACPI }.
- Extend intel_vsec_platform_info and intel_vsec_device with source enum
and ACPI discovery table pointer/
- When src==ACPI, skip BAR resource setup and copy the ACPI discovery
entries into the aux device.
No user-visible behavior change yet; this only wires ACPI data through vsec
in preparation for ACPI-enumerated PMT clients.
Signed-off-by: David E. Box <[email protected]>
---
v4:
- Use check_mul_overflow() instead of array_size() which was
incorrectly checking for 0 anyway.
v3:
- Re-send with all changes intended for v2 which was sent without them
being applied.
v2:
- Improve comment to clarify BAR resource setup doesn't apply to ACPI
discovery
- Add missing #include for kmemdup()
- Use array_size() for overflow protection
(review comments by Ilpo Järvinen)
drivers/platform/x86/intel/vsec.c | 23 +++++++++++++++++++++++
include/linux/intel_vsec.h | 20 +++++++++++++++++++-
2 files changed, 42 insertions(+), 1 deletion(-)
diff --git a/drivers/platform/x86/intel/vsec.c
b/drivers/platform/x86/intel/vsec.c
index 4aeb0728b435..cdbaa0a7f199 100644
--- a/drivers/platform/x86/intel/vsec.c
+++ b/drivers/platform/x86/intel/vsec.c
@@ -24,7 +24,9 @@
#include <linux/intel_vsec.h>
#include <linux/kernel.h>
#include <linux/module.h>
+#include <linux/overflow.h>
#include <linux/pci.h>
+#include <linux/string.h>
#include <linux/types.h>
#define PMT_XA_START 0
@@ -109,6 +111,7 @@ static void intel_vsec_dev_release(struct device *dev)
ida_free(intel_vsec_dev->ida, intel_vsec_dev->auxdev.id);
+ kfree(intel_vsec_dev->acpi_disc);
kfree(intel_vsec_dev->resource);
kfree(intel_vsec_dev);
}
@@ -320,6 +323,13 @@ static int intel_vsec_add_dev(struct device *dev, struct
intel_vsec_header *head
* auxiliary device driver.
*/
for (i = 0, tmp = res; i < header->num_entries; i++, tmp++) {
+ /*
+ * Skip resource mapping check for ACPI-based discovery
+ * since those tables are read from _DSD, not MMIO.
+ */
+ if (info->src == INTEL_VSEC_DISC_ACPI)
+ break;
+
tmp->start = base_addr + header->offset + i *
(header->entry_size * sizeof(u32));
tmp->end = tmp->start + (header->entry_size * sizeof(u32)) - 1;
tmp->flags = IORESOURCE_MEM;
@@ -338,6 +348,19 @@ static int intel_vsec_add_dev(struct device *dev, struct
intel_vsec_header *head
intel_vsec_dev->base_addr = info->base_addr;
intel_vsec_dev->priv_data = info->priv_data;
intel_vsec_dev->cap_id = cap_id;
+ intel_vsec_dev->src = info->src;
+
+ if (info->src == INTEL_VSEC_DISC_ACPI) {
+ size_t bytes;
+
+ if (check_mul_overflow(intel_vsec_dev->num_resources,
+ sizeof(*info->acpi_disc), &bytes))
+ return -EOVERFLOW;
+
+ intel_vsec_dev->acpi_disc = kmemdup(info->acpi_disc, bytes,
GFP_KERNEL);
+ if (!intel_vsec_dev->acpi_disc)
+ return -ENOMEM;
+ }
if (header->id == VSEC_ID_SDSI)
intel_vsec_dev->ida = &intel_vsec_sdsi_ida;
diff --git a/include/linux/intel_vsec.h b/include/linux/intel_vsec.h
index 4eecb2a6bac4..1fe5665a9d02 100644
--- a/include/linux/intel_vsec.h
+++ b/include/linux/intel_vsec.h
@@ -33,6 +33,11 @@ struct device;
struct pci_dev;
struct resource;
+enum intel_vsec_disc_source {
+ INTEL_VSEC_DISC_PCI, /* PCI, default */
+ INTEL_VSEC_DISC_ACPI, /* ACPI */
+};
+
enum intel_vsec_id {
VSEC_ID_TELEMETRY = 2,
VSEC_ID_WATCHER = 3,
@@ -103,6 +108,10 @@ struct vsec_feature_dependency {
* @parent: parent device in the auxbus chain
* @headers: list of headers to define the PMT client devices to create
* @deps: array of feature dependencies
+ * @acpi_disc: ACPI discovery tables, each entry is two QWORDs
+ * in little-endian format as defined by the PMT ACPI spec.
+ * Valid only when @provider == INTEL_VSEC_DISC_ACPI.
+ * @src: source of discovery table data
* @priv_data: private data, usable by parent devices, currently a callback
* @caps: bitmask of PMT capabilities for the given headers
* @quirks: bitmask of VSEC device quirks
@@ -113,6 +122,8 @@ struct intel_vsec_platform_info {
struct device *parent;
struct intel_vsec_header **headers;
const struct vsec_feature_dependency *deps;
+ u32 (*acpi_disc)[4];
+ enum intel_vsec_disc_source src;
void *priv_data;
unsigned long caps;
unsigned long quirks;
@@ -124,7 +135,12 @@ struct intel_vsec_platform_info {
* struct intel_vsec_device - Auxbus specific device information
* @auxdev: auxbus device struct for auxbus access
* @dev: struct device associated with the device
- * @resource: any resources shared by the parent
+ * @resource: PCI discovery resources (BAR windows), one per discovery
+ * instance. Valid only when @src == INTEL_VSEC_DISC_PCI
+ * @acpi_disc: ACPI discovery tables, each entry is two QWORDs
+ * in little-endian format as defined by the PMT ACPI spec.
+ * Valid only when @src == INTEL_VSEC_DISC_ACPI.
+ * @src: source of discovery table data
* @ida: id reference
* @num_resources: number of resources
* @id: xarray id
@@ -138,6 +154,8 @@ struct intel_vsec_device {
struct auxiliary_device auxdev;
struct device *dev;
struct resource *resource;
+ u32 (*acpi_disc)[4];
+ enum intel_vsec_disc_source src;
struct ida *ida;
int num_resources;
int id; /* xa */
--
2.43.0
