drm/nouveau/mmu/gp100: Remove unused/broken support for compression

From GP100 onwards it's not possible to initialise comptag RAM without
PMU firmware, which nouveau has no support for.

As such, this code is essentially a no-op and will always revert to the
equivalent non-compressed kind due to comptag allocation failure.  It's
also broken for the needs of VM_BIND/Vulkan.

Remove the code entirely to make way for supporting compression on GPUs
that support GSM-RM.

Signed-off-by: Ben Skeggs <bskeggs@nvidia.com>
Signed-off-by: Mohamed Ahmed <mohamedahmedegypt2001@gmail.com>
Signed-off-by: Mary Guillemard <mary@mary.zone>
Reviewed-by: Lyude Paul <lyude@redhat.com>
Reviewed-by: James Jones <jajones@nvidia.com>
Signed-off-by: Lyude Paul <lyude@redhat.com>
Link: https://patch.msgid.link/20251110-nouveau-compv6-v6-3-83b05475f57c@mary.zone

Author: Ben Skeggs

drivers/gpu/drm/nouveau/nvkm/subdev/mmu/vmmgp100.c

@@ -21,9 +21,7 @@
  */
 #include "vmm.h"
 
-#include <core/client.h>
 #include <subdev/fb.h>
-#include <subdev/ltc.h>
 #include <subdev/timer.h>
 #include <engine/gr.h>
 
@@ -117,8 +115,6 @@ gp100_vmm_pgt_pte(struct nvkm_vmm *vmm, struct nvkm_mmu_pt *pt,
 {
 	u64 data = (addr >> 4) | map->type;
 
-	map->type += ptes * map->ctag;
-
 	while (ptes--) {
 		VMM_WO064(pt, vmm, ptei++ * 8, data);
 		data += map->next;
@@ -142,7 +138,6 @@ gp100_vmm_pgt_dma(struct nvkm_vmm *vmm, struct nvkm_mmu_pt *pt,
 		while (ptes--) {
 			const u64 data = (*map->dma++ >> 4) | map->type;
 			VMM_WO064(pt, vmm, ptei++ * 8, data);
-			map->type += map->ctag;
 		}
 		nvkm_done(pt->memory);
 		return;
@@ -200,8 +195,6 @@ gp100_vmm_pd0_pte(struct nvkm_vmm *vmm, struct nvkm_mmu_pt *pt,
 {
 	u64 data = (addr >> 4) | map->type;
 
-	map->type += ptes * map->ctag;
-
 	while (ptes--) {
 		VMM_WO128(pt, vmm, ptei++ * 0x10, data, 0ULL);
 		data += map->next;
@@ -411,8 +404,6 @@ gp100_vmm_valid(struct nvkm_vmm *vmm, void *argv, u32 argc,
 		struct gp100_vmm_map_vn vn;
 		struct gp100_vmm_map_v0 v0;
 	} *args = argv;
-	struct nvkm_device *device = vmm->mmu->subdev.device;
-	struct nvkm_memory *memory = map->memory;
 	u8  kind, kind_inv, priv, ro, vol;
 	int kindn, aper, ret = -ENOSYS;
 	const u8 *kindm;
@@ -450,30 +441,8 @@ gp100_vmm_valid(struct nvkm_vmm *vmm, void *argv, u32 argc,
 	}
 
 	if (kindm[kind] != kind) {
-		u64 tags = nvkm_memory_size(memory) >> 16;
-		if (aper != 0 || !(page->type & NVKM_VMM_PAGE_COMP)) {
-			VMM_DEBUG(vmm, "comp %d %02x", aper, page->type);
-			return -EINVAL;
-		}
-
-		if (!map->no_comp) {
-			ret = nvkm_memory_tags_get(memory, device, tags,
-						   nvkm_ltc_tags_clear,
-						   &map->tags);
-			if (ret) {
-				VMM_DEBUG(vmm, "comp %d", ret);
-				return ret;
-			}
-		}
-
-		if (!map->no_comp && map->tags->mn) {
-			tags = map->tags->mn->offset + (map->offset >> 16);
-			map->ctag |= ((1ULL << page->shift) >> 16) << 36;
-			map->type |= tags << 36;
-			map->next |= map->ctag;
-		} else {
-			kind = kindm[kind];
-		}
+		/* Revert to non-compressed kind. */
+		kind = kindm[kind];
 	}
 
 	map->type |= BIT(0);
@@ -592,8 +561,8 @@ gp100_vmm = {
 		{ 47, &gp100_vmm_desc_16[4], NVKM_VMM_PAGE_Sxxx },
 		{ 38, &gp100_vmm_desc_16[3], NVKM_VMM_PAGE_Sxxx },
 		{ 29, &gp100_vmm_desc_16[2], NVKM_VMM_PAGE_Sxxx },
-		{ 21, &gp100_vmm_desc_16[1], NVKM_VMM_PAGE_SVxC },
-		{ 16, &gp100_vmm_desc_16[0], NVKM_VMM_PAGE_SVxC },
+		{ 21, &gp100_vmm_desc_16[1], NVKM_VMM_PAGE_SVxx },
+		{ 16, &gp100_vmm_desc_16[0], NVKM_VMM_PAGE_SVxx },
 		{ 12, &gp100_vmm_desc_12[0], NVKM_VMM_PAGE_SVHx },
 		{}
 	}

drivers/gpu/drm/nouveau/nvkm/subdev/mmu/vmmgp10b.c

@@ -34,8 +34,8 @@ gp10b_vmm = {
 		{ 47, &gp100_vmm_desc_16[4], NVKM_VMM_PAGE_Sxxx },
 		{ 38, &gp100_vmm_desc_16[3], NVKM_VMM_PAGE_Sxxx },
 		{ 29, &gp100_vmm_desc_16[2], NVKM_VMM_PAGE_Sxxx },
-		{ 21, &gp100_vmm_desc_16[1], NVKM_VMM_PAGE_SxHC },
-		{ 16, &gp100_vmm_desc_16[0], NVKM_VMM_PAGE_SxHC },
+		{ 21, &gp100_vmm_desc_16[1], NVKM_VMM_PAGE_SxHx },
+		{ 16, &gp100_vmm_desc_16[0], NVKM_VMM_PAGE_SxHx },
 		{ 12, &gp100_vmm_desc_12[0], NVKM_VMM_PAGE_SxHx },
 		{}
 	}