Re: [PATCH v3] pci: Handle 5-bit and 8-bit tag field

----- Mail original -----

If the hardware supports extended tag field (8-bit ones), then enabled it. This is usually done by the VBIOS, but not on some MBPs (see fdo#86537). In case extended tag field is not supported, 5-bit tag field is used which limits the possible values to 32. Apparently bits 7:0 of 0x8841c stores some number of outstanding requests, so cap it to 32 if extended tag is unsupported.

Fixes: fdo#86537

v2: Restrict changes to chipsets >= 0x84 v3:

• Add nvkm_pci_mask to pci.h
• Mask bit 8 before setting it

Signed-off-by: Pierre Moreau pierre.morrow@free.fr

Tested-by: Karol Herbst freedesktop@karolherbst.de

---

drm/nouveau/include/nvkm/subdev/pci.h | 1 + drm/nouveau/nvkm/subdev/pci/base.c | 25 +++++++++++++++++++++++++ 2 files changed, 26 insertions(+)

diff --git a/drm/nouveau/include/nvkm/subdev/pci.h b/drm/nouveau/include/nvkm/subdev/pci.h index 5b3c054..774ca66 100644 --- a/drm/nouveau/include/nvkm/subdev/pci.h +++ b/drm/nouveau/include/nvkm/subdev/pci.h @@ -24,6 +24,7 @@ struct nvkm_pci { u32 nvkm_pci_rd32(struct nvkm_pci *, u16 addr); void nvkm_pci_wr08(struct nvkm_pci *, u16 addr, u8 data); void nvkm_pci_wr32(struct nvkm_pci *, u16 addr, u32 data); +u32 nvkm_pci_mask(struct nvkm_pci *, u16 addr, u32 mask, u32 add); void nvkm_pci_rom_shadow(struct nvkm_pci *, bool shadow);

int nv04_pci_new(struct nvkm_device *, int, struct nvkm_pci **); diff --git a/drm/nouveau/nvkm/subdev/pci/base.c b/drm/nouveau/nvkm/subdev/pci/base.c index d1c148e..cb2835b 100644 --- a/drm/nouveau/nvkm/subdev/pci/base.c +++ b/drm/nouveau/nvkm/subdev/pci/base.c @@ -46,6 +46,14 @@ nvkm_pci_wr32(struct nvkm_pci *pci, u16 addr, u32 data) pci->func->wr32(pci, addr, data); }

+u32 +nvkm_pci_mask(struct nvkm_pci *pci, u16 addr, u32 mask, u32 add) +{

• u32 data = pci->func->rd32(pci, addr);
• pci->func->wr32(pci, addr, (data & ~mask) | add);
• return data;

+}

void nvkm_pci_rom_shadow(struct nvkm_pci *pci, bool shadow) { @@ -115,6 +123,23 @@ nvkm_pci_init(struct nvkm_subdev *subdev) if (ret) return ret;

• if (pci_is_pcie(pdev) && subdev->device->chipset >= 0x84) {

• /* Tag field is 8-bit long, regardless of EXT_TAG.
  

•  * However, if EXT_TAG is disabled, only the lower 5 bits of the
  

tag

•  * field should be used, limiting the number of request to 32.
  

•  *
  

•  * Apparently, 0x041c stores some limit on the number of requests
  

•  * possible, so if EXT_TAG is disabled, limit that requests number
  

to

•  * 32
  

•  *
  

•  * Fixes fdo#86537
  

•  */
  

• if (nvkm_pci_rd32(pci, 0x007c) & 0x00000020)
  

• 	nvkm_pci_mask(pci, 0x0080, 0x00000100, 0x00000100);
  

• else
  

• 	nvkm_pci_mask(pci, 0x041c, 0x00000060, 0x00000000);
  

• }
• pci->irq = pdev->irq; return ret;

}

2.5.2

---

dri-devel mailing list dri-devel@lists.freedesktop.org http://lists.freedesktop.org/mailman/listinfo/dri-devel