Files
linux/drivers/gpu/drm/xe/display/xe_plane_initial.c
Ville Syrjälä 01389846f7 drm/i915: Plumb 'dsb' all way to the plane hooks
We need to be able to do both MMIO and DSB based pipe/plane
programming. To that end plumb the 'dsb' all way from the top
into the plane commit hooks.

The compiler appears smart enough to combine the branches from
all the back-to-back register writes into a single branch.
So the generated asm ends up looking more or less like this:
plane_hook()
{
	if (dsb) {
		intel_dsb_reg_write();
		intel_dsb_reg_write();
		...
	} else {
		intel_de_write_fw();
		intel_de_write_fw();
		...
	}
}
which seems like a reasonably efficient way to do this.

An alternative I was also considering is some kind of closure
(register write function + display vs. dsb pointer passed to it).
That does result is smaller code as there are no branches anymore,
but having each register access go via function pointer sounds
less efficient.

Not that I actually measured the overhead of either approach yet.
Also the reg_rw tracepoint seems to be making a huge mess of the
generated code for the mmio path. And additionally there's some
kind of IS_GSI_REG() hack in __raw_uncore_read() which ends up
generating a pointless branch for every mmio register access.
So looks like there might be quite a bit of room for improvement
in the mmio path still.

Reviewed-by: Animesh Manna <animesh.manna@intel.com>
Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20240930170415.23841-12-ville.syrjala@linux.intel.com
2024-10-04 00:33:28 +03:00

311 lines
8.1 KiB
C

// SPDX-License-Identifier: MIT
/*
* Copyright © 2021 Intel Corporation
*/
/* for ioread64 */
#include <linux/io-64-nonatomic-lo-hi.h>
#include "regs/xe_gtt_defs.h"
#include "xe_ggtt.h"
#include "intel_atomic_plane.h"
#include "intel_crtc.h"
#include "intel_display.h"
#include "intel_display_types.h"
#include "intel_fb.h"
#include "intel_fb_pin.h"
#include "intel_frontbuffer.h"
#include "intel_plane_initial.h"
#include "xe_bo.h"
#include "xe_wa.h"
#include <generated/xe_wa_oob.h>
static bool
intel_reuse_initial_plane_obj(struct intel_crtc *this,
const struct intel_initial_plane_config plane_configs[],
struct drm_framebuffer **fb)
{
struct xe_device *xe = to_xe_device(this->base.dev);
struct intel_crtc *crtc;
for_each_intel_crtc(&xe->drm, crtc) {
struct intel_plane *plane =
to_intel_plane(crtc->base.primary);
const struct intel_plane_state *plane_state =
to_intel_plane_state(plane->base.state);
const struct intel_crtc_state *crtc_state =
to_intel_crtc_state(crtc->base.state);
if (!crtc_state->uapi.active)
continue;
if (!plane_state->ggtt_vma)
continue;
if (plane_configs[this->pipe].base == plane_configs[crtc->pipe].base) {
*fb = plane_state->hw.fb;
return true;
}
}
return false;
}
static struct xe_bo *
initial_plane_bo(struct xe_device *xe,
struct intel_initial_plane_config *plane_config)
{
struct xe_tile *tile0 = xe_device_get_root_tile(xe);
struct xe_bo *bo;
resource_size_t phys_base;
u32 base, size, flags;
u64 page_size = xe->info.vram_flags & XE_VRAM_FLAGS_NEED64K ? SZ_64K : SZ_4K;
if (plane_config->size == 0)
return NULL;
flags = XE_BO_FLAG_PINNED | XE_BO_FLAG_SCANOUT | XE_BO_FLAG_GGTT;
base = round_down(plane_config->base, page_size);
if (IS_DGFX(xe)) {
u64 __iomem *gte = tile0->mem.ggtt->gsm;
u64 pte;
gte += base / XE_PAGE_SIZE;
pte = ioread64(gte);
if (!(pte & XE_GGTT_PTE_DM)) {
drm_err(&xe->drm,
"Initial plane programming missing DM bit\n");
return NULL;
}
phys_base = pte & ~(page_size - 1);
flags |= XE_BO_FLAG_VRAM0;
/*
* We don't currently expect this to ever be placed in the
* stolen portion.
*/
if (phys_base >= tile0->mem.vram.usable_size) {
drm_err(&xe->drm,
"Initial plane programming using invalid range, phys_base=%pa\n",
&phys_base);
return NULL;
}
drm_dbg(&xe->drm,
"Using phys_base=%pa, based on initial plane programming\n",
&phys_base);
} else {
struct ttm_resource_manager *stolen = ttm_manager_type(&xe->ttm, XE_PL_STOLEN);
if (!stolen)
return NULL;
phys_base = base;
flags |= XE_BO_FLAG_STOLEN;
if (XE_WA(xe_root_mmio_gt(xe), 22019338487_display))
return NULL;
/*
* If the FB is too big, just don't use it since fbdev is not very
* important and we should probably use that space with FBC or other
* features.
*/
if (IS_ENABLED(CONFIG_FRAMEBUFFER_CONSOLE) &&
plane_config->size * 2 >> PAGE_SHIFT >= stolen->size)
return NULL;
}
size = round_up(plane_config->base + plane_config->size,
page_size);
size -= base;
bo = xe_bo_create_pin_map_at(xe, tile0, NULL, size, phys_base,
ttm_bo_type_kernel, flags);
if (IS_ERR(bo)) {
drm_dbg(&xe->drm,
"Failed to create bo phys_base=%pa size %u with flags %x: %li\n",
&phys_base, size, flags, PTR_ERR(bo));
return NULL;
}
return bo;
}
static bool
intel_alloc_initial_plane_obj(struct intel_crtc *crtc,
struct intel_initial_plane_config *plane_config)
{
struct xe_device *xe = to_xe_device(crtc->base.dev);
struct drm_mode_fb_cmd2 mode_cmd = { 0 };
struct drm_framebuffer *fb = &plane_config->fb->base;
struct xe_bo *bo;
switch (fb->modifier) {
case DRM_FORMAT_MOD_LINEAR:
case I915_FORMAT_MOD_X_TILED:
case I915_FORMAT_MOD_Y_TILED:
case I915_FORMAT_MOD_4_TILED:
break;
default:
drm_dbg_kms(&xe->drm,
"Unsupported modifier for initial FB: 0x%llx\n",
fb->modifier);
return false;
}
mode_cmd.pixel_format = fb->format->format;
mode_cmd.width = fb->width;
mode_cmd.height = fb->height;
mode_cmd.pitches[0] = fb->pitches[0];
mode_cmd.modifier[0] = fb->modifier;
mode_cmd.flags = DRM_MODE_FB_MODIFIERS;
bo = initial_plane_bo(xe, plane_config);
if (!bo)
return false;
if (intel_framebuffer_init(to_intel_framebuffer(fb),
&bo->ttm.base, &mode_cmd)) {
drm_dbg_kms(&xe->drm, "intel fb init failed\n");
goto err_bo;
}
/* Reference handed over to fb */
xe_bo_put(bo);
return true;
err_bo:
xe_bo_unpin_map_no_vm(bo);
return false;
}
static void
intel_find_initial_plane_obj(struct intel_crtc *crtc,
struct intel_initial_plane_config plane_configs[])
{
struct intel_initial_plane_config *plane_config =
&plane_configs[crtc->pipe];
struct intel_plane *plane =
to_intel_plane(crtc->base.primary);
struct intel_plane_state *plane_state =
to_intel_plane_state(plane->base.state);
struct intel_crtc_state *crtc_state =
to_intel_crtc_state(crtc->base.state);
struct drm_framebuffer *fb;
struct i915_vma *vma;
/*
* TODO:
* Disable planes if get_initial_plane_config() failed.
* Make sure things work if the surface base is not page aligned.
*/
if (!plane_config->fb)
return;
if (intel_alloc_initial_plane_obj(crtc, plane_config))
fb = &plane_config->fb->base;
else if (!intel_reuse_initial_plane_obj(crtc, plane_configs, &fb))
goto nofb;
plane_state->uapi.rotation = plane_config->rotation;
intel_fb_fill_view(to_intel_framebuffer(fb),
plane_state->uapi.rotation, &plane_state->view);
vma = intel_fb_pin_to_ggtt(fb, &plane_state->view.gtt,
0, 0, false, &plane_state->flags);
if (IS_ERR(vma))
goto nofb;
plane_state->ggtt_vma = vma;
plane_state->uapi.src_x = 0;
plane_state->uapi.src_y = 0;
plane_state->uapi.src_w = fb->width << 16;
plane_state->uapi.src_h = fb->height << 16;
plane_state->uapi.crtc_x = 0;
plane_state->uapi.crtc_y = 0;
plane_state->uapi.crtc_w = fb->width;
plane_state->uapi.crtc_h = fb->height;
plane_state->uapi.fb = fb;
drm_framebuffer_get(fb);
plane_state->uapi.crtc = &crtc->base;
intel_plane_copy_uapi_to_hw_state(plane_state, plane_state, crtc);
atomic_or(plane->frontbuffer_bit, &to_intel_frontbuffer(fb)->bits);
plane_config->vma = vma;
/*
* Flip to the newly created mapping ASAP, so we can re-use the
* first part of GGTT for WOPCM, prevent flickering, and prevent
* the lookup of sysmem scratch pages.
*/
plane->check_plane(crtc_state, plane_state);
plane->async_flip(NULL, plane, crtc_state, plane_state, true);
return;
nofb:
/*
* We've failed to reconstruct the BIOS FB. Current display state
* indicates that the primary plane is visible, but has a NULL FB,
* which will lead to problems later if we don't fix it up. The
* simplest solution is to just disable the primary plane now and
* pretend the BIOS never had it enabled.
*/
intel_plane_disable_noatomic(crtc, plane);
}
static void plane_config_fini(struct intel_initial_plane_config *plane_config)
{
if (plane_config->fb) {
struct drm_framebuffer *fb = &plane_config->fb->base;
/* We may only have the stub and not a full framebuffer */
if (drm_framebuffer_read_refcount(fb))
drm_framebuffer_put(fb);
else
kfree(fb);
}
}
void intel_initial_plane_config(struct drm_i915_private *i915)
{
struct intel_initial_plane_config plane_configs[I915_MAX_PIPES] = {};
struct intel_crtc *crtc;
for_each_intel_crtc(&i915->drm, crtc) {
struct intel_initial_plane_config *plane_config =
&plane_configs[crtc->pipe];
if (!to_intel_crtc_state(crtc->base.state)->uapi.active)
continue;
/*
* Note that reserving the BIOS fb up front prevents us
* from stuffing other stolen allocations like the ring
* on top. This prevents some ugliness at boot time, and
* can even allow for smooth boot transitions if the BIOS
* fb is large enough for the active pipe configuration.
*/
i915->display.funcs.display->get_initial_plane_config(crtc, plane_config);
/*
* If the fb is shared between multiple heads, we'll
* just get the first one.
*/
intel_find_initial_plane_obj(crtc, plane_configs);
if (i915->display.funcs.display->fixup_initial_plane_config(crtc, plane_config))
intel_crtc_wait_for_next_vblank(crtc);
plane_config_fini(plane_config);
}
}