drm/i915/display: Handle GMD_ID identification in display code

commit 12e6f6dc78e4f4a418648fb1a9c0cd2ae9b3430b upstream.

For platforms with GMD_ID support (i.e., everything MTL and beyond),
identification of the display IP present should be based on the contents
of the GMD_ID register rather than a PCI devid match.

Note that since GMD_ID readout requires access to the PCI BAR, a slight
change to the driver init sequence is needed --- pci_enable_device() is
now called before i915_driver_create().

v2:
 - Fix use of uninitialized i915 pointer in error path if
   pci_enable_device() fails before the i915 device is created.  (lkp)
 - Use drm_device parameter to intel_display_device_probe.  This goes
   against i915 conventions, but since the primary goal here is to make
   it easy to call this function from other drivers (like Xe) and since
   we don't need anything from the i915 structure, this seems like an
   exception where drm_device is a more natural fit.
v3:
 - Go back do drm_i915_private for intel_display_device_probe.  (Jani)
 - Move forward decl to top of header.  (Jani)

Signed-off-by: Matt Roper <matthew.d.roper@intel.com>
Reviewed-by: Andrzej Hajda <andrzej.hajda@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20230523195609.73627-6-matthew.d.roper@intel.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/drivers/gpu/drm/i915/display/intel_display_device.c b/drivers/gpu/drm/i915/display/intel_display_device.c
index 8c57d48e8270f1b619345d18a985d1781d2d7387..7e1af980e8ce592fca5b811c3d7fbdd337e49ec9 100644 (file)
--- a/drivers/gpu/drm/i915/display/intel_display_device.c
+++ b/drivers/gpu/drm/i915/display/intel_display_device.c
@@ -5,7 +5,10 @@
 
 #include <drm/i915_pciids.h>
 #include <drm/drm_color_mgmt.h>
+#include <linux/pci.h>
 
+#include "i915_drv.h"
+#include "i915_reg.h"
 #include "intel_display_device.h"
 #include "intel_display_power.h"
 #include "intel_display_reg_defs.h"
@@ -710,19 +713,73 @@ static const struct {
        INTEL_RPLP_IDS(&xe_lpd_display),
        INTEL_DG2_IDS(&xe_hpd_display),
 
-       /* FIXME: Replace this with a GMD_ID lookup */
-       INTEL_MTL_IDS(&xe_lpdp_display),
+       /*
+        * Do not add any GMD_ID-based platforms to this list.  They will
+        * be probed automatically based on the IP version reported by
+        * the hardware.
+        */
 };
 
+static const struct {
+       u16 ver;
+       u16 rel;
+       const struct intel_display_device_info *display;
+} gmdid_display_map[] = {
+       { 14,  0, &xe_lpdp_display },
+};
+
+static const struct intel_display_device_info *
+probe_gmdid_display(struct drm_i915_private *i915, u16 *ver, u16 *rel, u16 *step)
+{
+       struct pci_dev *pdev = to_pci_dev(i915->drm.dev);
+       void __iomem *addr;
+       u32 val;
+       int i;
+
+       addr = pci_iomap_range(pdev, 0, i915_mmio_reg_offset(GMD_ID_DISPLAY), sizeof(u32));
+       if (!addr) {
+               drm_err(&i915->drm, "Cannot map MMIO BAR to read display GMD_ID\n");
+               return &no_display;
+       }
+
+       val = ioread32(addr);
+       pci_iounmap(pdev, addr);
+
+       if (val == 0)
+               /* Platform doesn't have display */
+               return &no_display;
+
+       *ver = REG_FIELD_GET(GMD_ID_ARCH_MASK, val);
+       *rel = REG_FIELD_GET(GMD_ID_RELEASE_MASK, val);
+       *step = REG_FIELD_GET(GMD_ID_STEP, val);
+
+       for (i = 0; i < ARRAY_SIZE(gmdid_display_map); i++)
+               if (*ver == gmdid_display_map[i].ver &&
+                   *rel == gmdid_display_map[i].rel)
+                       return gmdid_display_map[i].display;
+
+       drm_err(&i915->drm, "Unrecognized display IP version %d.%02d; disabling display.\n",
+               *ver, *rel);
+       return &no_display;
+}
+
 const struct intel_display_device_info *
-intel_display_device_probe(u16 pci_devid)
+intel_display_device_probe(struct drm_i915_private *i915, bool has_gmdid,
+                          u16 *gmdid_ver, u16 *gmdid_rel, u16 *gmdid_step)
 {
+       struct pci_dev *pdev = to_pci_dev(i915->drm.dev);
        int i;
 
+       if (has_gmdid)
+               return probe_gmdid_display(i915, gmdid_ver, gmdid_rel, gmdid_step);
+
        for (i = 0; i < ARRAY_SIZE(intel_display_ids); i++) {
-               if (intel_display_ids[i].devid == pci_devid)
+               if (intel_display_ids[i].devid == pdev->device)
                        return intel_display_ids[i].info;
        }
 
+       drm_dbg(&i915->drm, "No display ID found for device ID %04x; disabling display.\n",
+               pdev->device);
+
        return &no_display;
 }

diff --git a/drivers/gpu/drm/i915/display/intel_display_device.h b/drivers/gpu/drm/i915/display/intel_display_device.h
index 1f7d08b3ad6b1cc81b16968ba8d9494c7ab4b3e7..d1d11581d85dc6fbd95b4e1e724659ad685412d8 100644 (file)
--- a/drivers/gpu/drm/i915/display/intel_display_device.h
+++ b/drivers/gpu/drm/i915/display/intel_display_device.h
@@ -10,6 +10,8 @@
 
 #include "display/intel_display_limits.h"
 
+struct drm_i915_private;
+
 #define DEV_INFO_DISPLAY_FOR_EACH_FLAG(func) \
        /* Keep in alphabetical order */ \
        func(cursor_needs_physical); \
@@ -81,6 +83,7 @@ struct intel_display_device_info {
 };
 
 const struct intel_display_device_info *
-intel_display_device_probe(u16 pci_devid);
+intel_display_device_probe(struct drm_i915_private *i915, bool has_gmdid,
+                          u16 *ver, u16 *rel, u16 *step);
 
 #endif

diff --git a/drivers/gpu/drm/i915/i915_driver.c b/drivers/gpu/drm/i915/i915_driver.c
index 3d73dc3cec112b2d5b4df883362ff017e2611fed..664c55f0ed4c51ff4bd6fdc6beb481c6238fe03f 100644 (file)
--- a/drivers/gpu/drm/i915/i915_driver.c
+++ b/drivers/gpu/drm/i915/i915_driver.c
@@ -739,13 +739,17 @@ int i915_driver_probe(struct pci_dev *pdev, const struct pci_device_id *ent)
        struct drm_i915_private *i915;
        int ret;
 
-       i915 = i915_driver_create(pdev, ent);
-       if (IS_ERR(i915))
-               return PTR_ERR(i915);
-
        ret = pci_enable_device(pdev);
-       if (ret)
-               goto out_fini;
+       if (ret) {
+               pr_err("Failed to enable graphics device: %pe\n", ERR_PTR(ret));
+               return ret;
+       }
+
+       i915 = i915_driver_create(pdev, ent);
+       if (IS_ERR(i915)) {
+               ret = PTR_ERR(i915);
+               goto out_pci_disable;
+       }
 
        ret = i915_driver_early_probe(i915);
        if (ret < 0)
@@ -828,7 +832,6 @@ out_runtime_pm_put:
        i915_driver_late_release(i915);
 out_pci_disable:
        pci_disable_device(pdev);
-out_fini:
        i915_probe_error(i915, "Device initialization failed (%d)\n", ret);
        return ret;
 }

diff --git a/drivers/gpu/drm/i915/intel_device_info.c b/drivers/gpu/drm/i915/intel_device_info.c
index 79523e55ca9c413b395ef928adf7a06c5783fa80..2f79d232b04a94ac2723494e4e8c8158d56505aa 100644 (file)
--- a/drivers/gpu/drm/i915/intel_device_info.c
+++ b/drivers/gpu/drm/i915/intel_device_info.c
@@ -345,7 +345,6 @@ static void ip_ver_read(struct drm_i915_private *i915, u32 offset, struct intel_
 static void intel_ipver_early_init(struct drm_i915_private *i915)
 {
        struct intel_runtime_info *runtime = RUNTIME_INFO(i915);
-       struct intel_display_runtime_info *display_runtime = DISPLAY_RUNTIME_INFO(i915);
 
        if (!HAS_GMD_ID(i915)) {
                drm_WARN_ON(&i915->drm, RUNTIME_INFO(i915)->graphics.ip.ver > 12);
@@ -366,8 +365,6 @@ static void intel_ipver_early_init(struct drm_i915_private *i915)
                RUNTIME_INFO(i915)->graphics.ip.ver = 12;
                RUNTIME_INFO(i915)->graphics.ip.rel = 70;
        }
-       ip_ver_read(i915, i915_mmio_reg_offset(GMD_ID_DISPLAY),
-                   (struct intel_ip_version *)&display_runtime->ip);
        ip_ver_read(i915, i915_mmio_reg_offset(GMD_ID_MEDIA),
                    &runtime->media.ip);
 }
@@ -574,6 +571,7 @@ void intel_device_info_driver_create(struct drm_i915_private *i915,
 {
        struct intel_device_info *info;
        struct intel_runtime_info *runtime;
+       u16 ver, rel, step;
 
        /* Setup the write-once "constant" device info */
        info = mkwrite_device_info(i915);
@@ -584,11 +582,18 @@ void intel_device_info_driver_create(struct drm_i915_private *i915,
        memcpy(runtime, &INTEL_INFO(i915)->__runtime, sizeof(*runtime));
 
        /* Probe display support */
-       info->display = intel_display_device_probe(device_id);
+       info->display = intel_display_device_probe(i915, info->has_gmd_id,
+                                                  &ver, &rel, &step);
        memcpy(DISPLAY_RUNTIME_INFO(i915),
               &DISPLAY_INFO(i915)->__runtime_defaults,
               sizeof(*DISPLAY_RUNTIME_INFO(i915)));
 
+       if (info->has_gmd_id) {
+               DISPLAY_RUNTIME_INFO(i915)->ip.ver = ver;
+               DISPLAY_RUNTIME_INFO(i915)->ip.rel = rel;
+               DISPLAY_RUNTIME_INFO(i915)->ip.step = step;
+       }
+
        runtime->device_id = device_id;
 }