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author | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-04-07 18:49:45 +0000 |
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committer | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-04-07 18:49:45 +0000 |
commit | 2c3c1048746a4622d8c89a29670120dc8fab93c4 (patch) | |
tree | 848558de17fb3008cdf4d861b01ac7781903ce39 /drivers/gpu/drm/nouveau/nouveau_dma.c | |
parent | Initial commit. (diff) | |
download | linux-2c3c1048746a4622d8c89a29670120dc8fab93c4.tar.xz linux-2c3c1048746a4622d8c89a29670120dc8fab93c4.zip |
Adding upstream version 6.1.76.upstream/6.1.76
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'drivers/gpu/drm/nouveau/nouveau_dma.c')
-rw-r--r-- | drivers/gpu/drm/nouveau/nouveau_dma.c | 246 |
1 files changed, 246 insertions, 0 deletions
diff --git a/drivers/gpu/drm/nouveau/nouveau_dma.c b/drivers/gpu/drm/nouveau/nouveau_dma.c new file mode 100644 index 000000000..ddb75d80b --- /dev/null +++ b/drivers/gpu/drm/nouveau/nouveau_dma.c @@ -0,0 +1,246 @@ +/* + * Copyright (C) 2007 Ben Skeggs. + * All Rights Reserved. + * + * Permission is hereby granted, free of charge, to any person obtaining + * a copy of this software and associated documentation files (the + * "Software"), to deal in the Software without restriction, including + * without limitation the rights to use, copy, modify, merge, publish, + * distribute, sublicense, and/or sell copies of the Software, and to + * permit persons to whom the Software is furnished to do so, subject to + * the following conditions: + * + * The above copyright notice and this permission notice (including the + * next paragraph) shall be included in all copies or substantial + * portions of the Software. + * + * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, + * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF + * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. + * IN NO EVENT SHALL THE COPYRIGHT OWNER(S) AND/OR ITS SUPPLIERS BE + * LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION + * OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION + * WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE. + * + */ + +#include "nouveau_drv.h" +#include "nouveau_dma.h" +#include "nouveau_vmm.h" + +#include <nvif/user.h> + +/* Fetch and adjust GPU GET pointer + * + * Returns: + * value >= 0, the adjusted GET pointer + * -EINVAL if GET pointer currently outside main push buffer + * -EBUSY if timeout exceeded + */ +static inline int +READ_GET(struct nouveau_channel *chan, uint64_t *prev_get, int *timeout) +{ + uint64_t val; + + val = nvif_rd32(&chan->user, chan->user_get); + if (chan->user_get_hi) + val |= (uint64_t)nvif_rd32(&chan->user, chan->user_get_hi) << 32; + + /* reset counter as long as GET is still advancing, this is + * to avoid misdetecting a GPU lockup if the GPU happens to + * just be processing an operation that takes a long time + */ + if (val != *prev_get) { + *prev_get = val; + *timeout = 0; + } + + if ((++*timeout & 0xff) == 0) { + udelay(1); + if (*timeout > 100000) + return -EBUSY; + } + + if (val < chan->push.addr || + val > chan->push.addr + (chan->dma.max << 2)) + return -EINVAL; + + return (val - chan->push.addr) >> 2; +} + +void +nv50_dma_push(struct nouveau_channel *chan, u64 offset, int length) +{ + struct nvif_user *user = &chan->drm->client.device.user; + struct nouveau_bo *pb = chan->push.buffer; + int ip = (chan->dma.ib_put * 2) + chan->dma.ib_base; + + BUG_ON(chan->dma.ib_free < 1); + + nouveau_bo_wr32(pb, ip++, lower_32_bits(offset)); + nouveau_bo_wr32(pb, ip++, upper_32_bits(offset) | length << 8); + + chan->dma.ib_put = (chan->dma.ib_put + 1) & chan->dma.ib_max; + + mb(); + /* Flush writes. */ + nouveau_bo_rd32(pb, 0); + + nvif_wr32(&chan->user, 0x8c, chan->dma.ib_put); + if (user->func && user->func->doorbell) + user->func->doorbell(user, chan->token); + chan->dma.ib_free--; +} + +static int +nv50_dma_push_wait(struct nouveau_channel *chan, int count) +{ + uint32_t cnt = 0, prev_get = 0; + + while (chan->dma.ib_free < count) { + uint32_t get = nvif_rd32(&chan->user, 0x88); + if (get != prev_get) { + prev_get = get; + cnt = 0; + } + + if ((++cnt & 0xff) == 0) { + udelay(1); + if (cnt > 100000) + return -EBUSY; + } + + chan->dma.ib_free = get - chan->dma.ib_put; + if (chan->dma.ib_free <= 0) + chan->dma.ib_free += chan->dma.ib_max; + } + + return 0; +} + +static int +nv50_dma_wait(struct nouveau_channel *chan, int slots, int count) +{ + uint64_t prev_get = 0; + int ret, cnt = 0; + + ret = nv50_dma_push_wait(chan, slots + 1); + if (unlikely(ret)) + return ret; + + while (chan->dma.free < count) { + int get = READ_GET(chan, &prev_get, &cnt); + if (unlikely(get < 0)) { + if (get == -EINVAL) + continue; + + return get; + } + + if (get <= chan->dma.cur) { + chan->dma.free = chan->dma.max - chan->dma.cur; + if (chan->dma.free >= count) + break; + + FIRE_RING(chan); + do { + get = READ_GET(chan, &prev_get, &cnt); + if (unlikely(get < 0)) { + if (get == -EINVAL) + continue; + return get; + } + } while (get == 0); + chan->dma.cur = 0; + chan->dma.put = 0; + } + + chan->dma.free = get - chan->dma.cur - 1; + } + + return 0; +} + +int +nouveau_dma_wait(struct nouveau_channel *chan, int slots, int size) +{ + uint64_t prev_get = 0; + int cnt = 0, get; + + if (chan->dma.ib_max) + return nv50_dma_wait(chan, slots, size); + + while (chan->dma.free < size) { + get = READ_GET(chan, &prev_get, &cnt); + if (unlikely(get == -EBUSY)) + return -EBUSY; + + /* loop until we have a usable GET pointer. the value + * we read from the GPU may be outside the main ring if + * PFIFO is processing a buffer called from the main ring, + * discard these values until something sensible is seen. + * + * the other case we discard GET is while the GPU is fetching + * from the SKIPS area, so the code below doesn't have to deal + * with some fun corner cases. + */ + if (unlikely(get == -EINVAL) || get < NOUVEAU_DMA_SKIPS) + continue; + + if (get <= chan->dma.cur) { + /* engine is fetching behind us, or is completely + * idle (GET == PUT) so we have free space up until + * the end of the push buffer + * + * we can only hit that path once per call due to + * looping back to the beginning of the push buffer, + * we'll hit the fetching-ahead-of-us path from that + * point on. + * + * the *one* exception to that rule is if we read + * GET==PUT, in which case the below conditional will + * always succeed and break us out of the wait loop. + */ + chan->dma.free = chan->dma.max - chan->dma.cur; + if (chan->dma.free >= size) + break; + + /* not enough space left at the end of the push buffer, + * instruct the GPU to jump back to the start right + * after processing the currently pending commands. + */ + OUT_RING(chan, chan->push.addr | 0x20000000); + + /* wait for GET to depart from the skips area. + * prevents writing GET==PUT and causing a race + * condition that causes us to think the GPU is + * idle when it's not. + */ + do { + get = READ_GET(chan, &prev_get, &cnt); + if (unlikely(get == -EBUSY)) + return -EBUSY; + if (unlikely(get == -EINVAL)) + continue; + } while (get <= NOUVEAU_DMA_SKIPS); + WRITE_PUT(NOUVEAU_DMA_SKIPS); + + /* we're now submitting commands at the start of + * the push buffer. + */ + chan->dma.cur = + chan->dma.put = NOUVEAU_DMA_SKIPS; + } + + /* engine fetching ahead of us, we have space up until the + * current GET pointer. the "- 1" is to ensure there's + * space left to emit a jump back to the beginning of the + * push buffer if we require it. we can never get GET == PUT + * here, so this is safe. + */ + chan->dma.free = get - chan->dma.cur - 1; + } + + return 0; +} + |