diff mbox series

[v2,2/9] vfio/igd: align generation with i915 kernel driver

Message ID 20241203133548.38252-3-tomitamoeko@gmail.com (mailing list archive)
State New
Headers show
Series vfio/igd: Enable legacy mode on more devices | expand

Commit Message

Tomita Moeko Dec. 3, 2024, 1:35 p.m. UTC
Define the igd device generations according to i915 kernel driver to
avoid confusion, and adjust comment placement to clearly reflect the
relationship between ids and devices.

The condition of how GTT stolen memory size is calculated is changed
accordingly as GGMS is in multiple of 2 starting from gen 8.

Signed-off-by: Tomita Moeko <tomitamoeko@gmail.com>
---
 hw/vfio/igd.c | 44 ++++++++++++++++++++++----------------------
 1 file changed, 22 insertions(+), 22 deletions(-)

Comments

Corvin Köhne Dec. 3, 2024, 4:07 p.m. UTC | #1
On Tue, 2024-12-03 at 21:35 +0800, Tomita Moeko wrote:
> CAUTION: External Email!!
> Define the igd device generations according to i915 kernel driver to
> avoid confusion, and adjust comment placement to clearly reflect the
> relationship between ids and devices.
> 
> The condition of how GTT stolen memory size is calculated is changed
> accordingly as GGMS is in multiple of 2 starting from gen 8.
> 
> Signed-off-by: Tomita Moeko <tomitamoeko@gmail.com>
> ---
>  hw/vfio/igd.c | 44 ++++++++++++++++++++++----------------------
>  1 file changed, 22 insertions(+), 22 deletions(-)
> 
> diff --git a/hw/vfio/igd.c b/hw/vfio/igd.c
> index 6ba3045bf3..2ede72d243 100644
> --- a/hw/vfio/igd.c
> +++ b/hw/vfio/igd.c
> @@ -59,33 +59,33 @@
>   */
>  static int igd_gen(VFIOPCIDevice *vdev)
>  {
> -    if ((vdev->device_id & 0xfff) == 0xa84) {
> -        return 8; /* Broxton */
> +    /*
> +     * Device IDs for Broxton/Apollo Lake are 0x0a84, 0x1a84, 0x1a85, 0x5a84
> +     * and 0x5a85
> +     */
> +    if ((vdev->device_id & 0xffe) == 0xa84) {
> +        return 9;
>      }
>  

I'd slightly prefer matching those ids explicitly. At some point it may even
make more sense to copy the pciids of Linux and reuse them [1].

Note that this is just a suggestion!

[1]
https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/tree/include/drm/intel/i915_pciids.h?h=v6.12

>      switch (vdev->device_id & 0xff00) {
> -    /* SandyBridge, IvyBridge, ValleyView, Haswell */
> -    case 0x0100:
> -    case 0x0400:
> -    case 0x0a00:
> -    case 0x0c00:
> -    case 0x0d00:
> -    case 0x0f00:
> +    case 0x0100:    /* SandyBridge, IvyBridge */
>          return 6;
> -    /* BroadWell, CherryView, SkyLake, KabyLake */
> -    case 0x1600:
> -    case 0x1900:
> -    case 0x2200:
> -    case 0x5900:
> +    case 0x0400:    /* Haswell */
> +    case 0x0a00:    /* Haswell */
> +    case 0x0c00:    /* Haswell */
> +    case 0x0d00:    /* Haswell */
> +    case 0x0f00:    /* Valleyview/Bay Trail */
> +        return 7;
> +    case 0x1600:    /* Broadwell */
> +    case 0x2200:    /* Cherryview */
>          return 8;
> -    /* CoffeeLake */
> -    case 0x3e00:
> +    case 0x1900:    /* Skylake */
> +    case 0x5900:    /* Kaby Lake */
> +    case 0x3e00:    /* Coffee Lake */
>          return 9;
> -    /* ElkhartLake */
> -    case 0x4500:
> +    case 0x4500:    /* Elkhart Lake */
>          return 11;
> -    /* TigerLake */
> -    case 0x9A00:
> +    case 0x9A00:    /* Tiger Lake */
>          return 12;
>      }
>  
> @@ -258,7 +258,7 @@ static int vfio_igd_gtt_max(VFIOPCIDevice *vdev)
>  
>      gmch = vfio_pci_read_config(&vdev->pdev, IGD_GMCH, sizeof(gmch));
>      ggms = (gmch >> (gen < 8 ? 8 : 6)) & 0x3;
> -    if (gen > 6) {
> +    if (gen >= 8) {
>          ggms = 1 << ggms;
>      }
>  
> @@ -668,7 +668,7 @@ void vfio_probe_igd_bar4_quirk(VFIOPCIDevice *vdev, int
> nr)
>  
>      /* Determine the size of stolen memory needed for GTT */
>      ggms_mb = (gmch >> (gen < 8 ? 8 : 6)) & 0x3;
> -    if (gen > 6) {
> +    if (gen >= 8) {
>          ggms_mb = 1 << ggms_mb;
>      }
>  

Reviewed-by: Corvin Köhne <c.koehne@beckhoff.com>
diff mbox series

Patch

diff --git a/hw/vfio/igd.c b/hw/vfio/igd.c
index 6ba3045bf3..2ede72d243 100644
--- a/hw/vfio/igd.c
+++ b/hw/vfio/igd.c
@@ -59,33 +59,33 @@ 
  */
 static int igd_gen(VFIOPCIDevice *vdev)
 {
-    if ((vdev->device_id & 0xfff) == 0xa84) {
-        return 8; /* Broxton */
+    /*
+     * Device IDs for Broxton/Apollo Lake are 0x0a84, 0x1a84, 0x1a85, 0x5a84
+     * and 0x5a85
+     */
+    if ((vdev->device_id & 0xffe) == 0xa84) {
+        return 9;
     }
 
     switch (vdev->device_id & 0xff00) {
-    /* SandyBridge, IvyBridge, ValleyView, Haswell */
-    case 0x0100:
-    case 0x0400:
-    case 0x0a00:
-    case 0x0c00:
-    case 0x0d00:
-    case 0x0f00:
+    case 0x0100:    /* SandyBridge, IvyBridge */
         return 6;
-    /* BroadWell, CherryView, SkyLake, KabyLake */
-    case 0x1600:
-    case 0x1900:
-    case 0x2200:
-    case 0x5900:
+    case 0x0400:    /* Haswell */
+    case 0x0a00:    /* Haswell */
+    case 0x0c00:    /* Haswell */
+    case 0x0d00:    /* Haswell */
+    case 0x0f00:    /* Valleyview/Bay Trail */
+        return 7;
+    case 0x1600:    /* Broadwell */
+    case 0x2200:    /* Cherryview */
         return 8;
-    /* CoffeeLake */
-    case 0x3e00:
+    case 0x1900:    /* Skylake */
+    case 0x5900:    /* Kaby Lake */
+    case 0x3e00:    /* Coffee Lake */
         return 9;
-    /* ElkhartLake */
-    case 0x4500:
+    case 0x4500:    /* Elkhart Lake */
         return 11;
-    /* TigerLake */
-    case 0x9A00:
+    case 0x9A00:    /* Tiger Lake */
         return 12;
     }
 
@@ -258,7 +258,7 @@  static int vfio_igd_gtt_max(VFIOPCIDevice *vdev)
 
     gmch = vfio_pci_read_config(&vdev->pdev, IGD_GMCH, sizeof(gmch));
     ggms = (gmch >> (gen < 8 ? 8 : 6)) & 0x3;
-    if (gen > 6) {
+    if (gen >= 8) {
         ggms = 1 << ggms;
     }
 
@@ -668,7 +668,7 @@  void vfio_probe_igd_bar4_quirk(VFIOPCIDevice *vdev, int nr)
 
     /* Determine the size of stolen memory needed for GTT */
     ggms_mb = (gmch >> (gen < 8 ? 8 : 6)) & 0x3;
-    if (gen > 6) {
+    if (gen >= 8) {
         ggms_mb = 1 << ggms_mb;
     }