Re: [RFC 07/16] drm/nouveau/bar/nvc0: support chips without BAR3

From: Ben Skeggs
Date: Mon Feb 03 2014 - 22:54:59 EST


On Sat, Feb 1, 2014 at 1:16 PM, Alexandre Courbot <acourbot@xxxxxxxxxx> wrote:
> Adapt the NVC0 BAR driver to make it able to support chips that do not
> expose a BAR3. When this happens, BAR1 is then used for USERD mapping
> and the BAR alloc() functions is disabled, making GPU objects unable
> to rely on BAR for data access and falling back to PRAMIN.
>
> Signed-off-by: Alexandre Courbot <acourbot@xxxxxxxxxx>
> ---
> drivers/gpu/drm/nouveau/core/subdev/bar/nvc0.c | 115 +++++++++++++------------
> 1 file changed, 61 insertions(+), 54 deletions(-)
>
> diff --git a/drivers/gpu/drm/nouveau/core/subdev/bar/nvc0.c b/drivers/gpu/drm/nouveau/core/subdev/bar/nvc0.c
> index 3f30db6..c2bb0e5 100644
> --- a/drivers/gpu/drm/nouveau/core/subdev/bar/nvc0.c
> +++ b/drivers/gpu/drm/nouveau/core/subdev/bar/nvc0.c
> @@ -79,87 +79,88 @@ nvc0_bar_unmap(struct nouveau_bar *bar, struct nouveau_vma *vma)
> }
>
> static int
> -nvc0_bar_ctor(struct nouveau_object *parent, struct nouveau_object *engine,
> - struct nouveau_oclass *oclass, void *data, u32 size,
> - struct nouveau_object **pobject)
> +nvc0_bar_init_vm(struct nvc0_bar_priv *priv, int nr, int bar)
> {
> - struct nouveau_device *device = nv_device(parent);
> - struct nvc0_bar_priv *priv;
> + struct nouveau_device *device = nv_device(&priv->base);
> struct nouveau_gpuobj *mem;
> struct nouveau_vm *vm;
> + resource_size_t bar_len;
> int ret;
>
> - ret = nouveau_bar_create(parent, engine, oclass, &priv);
> - *pobject = nv_object(priv);
> - if (ret)
> - return ret;
> -
> - /* BAR3 */
> ret = nouveau_gpuobj_new(nv_object(priv), NULL, 0x1000, 0, 0,
> - &priv->bar[0].mem);
> - mem = priv->bar[0].mem;
> + &priv->bar[nr].mem);
> + mem = priv->bar[nr].mem;
> if (ret)
> return ret;
>
> ret = nouveau_gpuobj_new(nv_object(priv), NULL, 0x8000, 0, 0,
> - &priv->bar[0].pgd);
> + &priv->bar[nr].pgd);
> if (ret)
> return ret;
>
> - ret = nouveau_vm_new(device, 0, nv_device_resource_len(device, 3), 0, &vm);
> + bar_len = nv_device_resource_len(device, bar);
> +
> + ret = nouveau_vm_new(device, 0, bar_len, 0, &vm);
> if (ret)
> return ret;
>
> atomic_inc(&vm->engref[NVDEV_SUBDEV_BAR]);
>
> - ret = nouveau_gpuobj_new(nv_object(priv), NULL,
> - (nv_device_resource_len(device, 3) >> 12) * 8,
> - 0x1000, NVOBJ_FLAG_ZERO_ALLOC,
> - &vm->pgt[0].obj[0]);
> - vm->pgt[0].refcount[0] = 1;
> - if (ret)
> - return ret;
> + /*
> + * Bootstrap page table lookup.
> + */
> + if (bar == 3) {
> + ret = nouveau_gpuobj_new(nv_object(priv), NULL,
> + (bar_len >> 12) * 8, 0x1000,
> + NVOBJ_FLAG_ZERO_ALLOC,
> + &vm->pgt[0].obj[0]);
> + vm->pgt[0].refcount[0] = 1;
> + if (ret)
> + return ret;
> + }
>
> - ret = nouveau_vm_ref(vm, &priv->bar[0].vm, priv->bar[0].pgd);
> + ret = nouveau_vm_ref(vm, &priv->bar[nr].vm, priv->bar[nr].pgd);
> nouveau_vm_ref(NULL, &vm, NULL);
> if (ret)
> return ret;
>
> - nv_wo32(mem, 0x0200, lower_32_bits(priv->bar[0].pgd->addr));
> - nv_wo32(mem, 0x0204, upper_32_bits(priv->bar[0].pgd->addr));
> - nv_wo32(mem, 0x0208, lower_32_bits(nv_device_resource_len(device, 3) - 1));
> - nv_wo32(mem, 0x020c, upper_32_bits(nv_device_resource_len(device, 3) - 1));
> + nv_wo32(mem, 0x0200, lower_32_bits(priv->bar[nr].pgd->addr));
> + nv_wo32(mem, 0x0204, upper_32_bits(priv->bar[nr].pgd->addr));
> + nv_wo32(mem, 0x0208, lower_32_bits(bar_len - 1));
> + nv_wo32(mem, 0x020c, upper_32_bits(bar_len - 1));
>
> - /* BAR1 */
> - ret = nouveau_gpuobj_new(nv_object(priv), NULL, 0x1000, 0, 0,
> - &priv->bar[1].mem);
> - mem = priv->bar[1].mem;
> - if (ret)
> - return ret;
> + return 0;
> +}
>
> - ret = nouveau_gpuobj_new(nv_object(priv), NULL, 0x8000, 0, 0,
> - &priv->bar[1].pgd);
> - if (ret)
> - return ret;
> +static int
> +nvc0_bar_ctor(struct nouveau_object *parent, struct nouveau_object *engine,
> + struct nouveau_oclass *oclass, void *data, u32 size,
> + struct nouveau_object **pobject)
> +{
> + struct nouveau_device *device = nv_device(parent);
> + struct nvc0_bar_priv *priv;
> + bool has_bar3 = nv_device_resource_len(device, 3) != 0;
> + int ret;
>
> - ret = nouveau_vm_new(device, 0, nv_device_resource_len(device, 1), 0, &vm);
> + ret = nouveau_bar_create(parent, engine, oclass, &priv);
> + *pobject = nv_object(priv);
> if (ret)
> return ret;
>
> - atomic_inc(&vm->engref[NVDEV_SUBDEV_BAR]);
> + /* BAR3 */
> + if (has_bar3) {
> + ret = nvc0_bar_init_vm(priv, 0, 3);
> + if (ret)
> + return ret;
> + priv->base.alloc = nouveau_bar_alloc;
> + priv->base.kmap = nvc0_bar_kmap;
> + }
>
> - ret = nouveau_vm_ref(vm, &priv->bar[1].vm, priv->bar[1].pgd);
> - nouveau_vm_ref(NULL, &vm, NULL);
> + /* BAR1 */
> + ret = nvc0_bar_init_vm(priv, 1, 1);
> if (ret)
> return ret;
>
> - nv_wo32(mem, 0x0200, lower_32_bits(priv->bar[1].pgd->addr));
> - nv_wo32(mem, 0x0204, upper_32_bits(priv->bar[1].pgd->addr));
> - nv_wo32(mem, 0x0208, lower_32_bits(nv_device_resource_len(device, 1) - 1));
> - nv_wo32(mem, 0x020c, upper_32_bits(nv_device_resource_len(device, 1) - 1));
> -
> - priv->base.alloc = nouveau_bar_alloc;
> - priv->base.kmap = nvc0_bar_kmap;
> priv->base.umap = nvc0_bar_umap;
> priv->base.unmap = nvc0_bar_unmap;
> priv->base.flush = nv84_bar_flush;
> @@ -176,12 +177,16 @@ nvc0_bar_dtor(struct nouveau_object *object)
> nouveau_gpuobj_ref(NULL, &priv->bar[1].pgd);
> nouveau_gpuobj_ref(NULL, &priv->bar[1].mem);
>
> - if (priv->bar[0].vm) {
> - nouveau_gpuobj_ref(NULL, &priv->bar[0].vm->pgt[0].obj[0]);
> - nouveau_vm_ref(NULL, &priv->bar[0].vm, priv->bar[0].pgd);
> + if (priv->bar[0].mem) {
> + if (priv->bar[0].vm) {
> + nouveau_gpuobj_ref(NULL,
> + &priv->bar[0].vm->pgt[0].obj[0]);
> + nouveau_vm_ref(NULL, &priv->bar[0].vm,
> + priv->bar[0].pgd);
> + }
> + nouveau_gpuobj_ref(NULL, &priv->bar[0].pgd);
> + nouveau_gpuobj_ref(NULL, &priv->bar[0].mem);
> }
> - nouveau_gpuobj_ref(NULL, &priv->bar[0].pgd);
> - nouveau_gpuobj_ref(NULL, &priv->bar[0].mem);
Did the conditional on priv->bar[0].mem fix anything here? The ref()
functions called are designed to handle the NULL pointers already.

>
> nouveau_bar_destroy(&priv->base);
> }
> @@ -201,7 +206,9 @@ nvc0_bar_init(struct nouveau_object *object)
> nv_mask(priv, 0x100c80, 0x00000001, 0x00000000);
>
> nv_wr32(priv, 0x001704, 0x80000000 | priv->bar[1].mem->addr >> 12);
> - nv_wr32(priv, 0x001714, 0xc0000000 | priv->bar[0].mem->addr >> 12);
> + if (priv->bar[0].mem)
> + nv_wr32(priv, 0x001714,
> + 0xc0000000 | priv->bar[0].mem->addr >> 12);
> return 0;
> }
>
> --
> 1.8.5.3
>
> _______________________________________________
> dri-devel mailing list
> dri-devel@xxxxxxxxxxxxxxxxxxxxx
> http://lists.freedesktop.org/mailman/listinfo/dri-devel
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/