[PATCH] drm/i915: Piggyback opregion vbt to store vbt read from flash/oprom
Ville Syrjälä
ville.syrjala at linux.intel.com
Wed Dec 20 02:13:53 UTC 2023
On Tue, Dec 19, 2023 at 05:49:52PM -0800, Radhakrishna Sripada wrote:
> Discrete cards do not have ACPI opregion. The vbt is stored in a special
> flash accessible by the display controller. In order to access the vbt
> in such cases, re-use the vbt, vbt_size fields in the opregion structure.
Why?
>
> We should move away from storing the vbt in the opregion and store it,
> if required in the vbt structure.
>
> Signed-off-by: Radhakrishna Sripada <radhakrishna.sripada at intel.com>
> ---
> drivers/gpu/drm/i915/display/intel_bios.c | 44 ++++++++++---------
> drivers/gpu/drm/i915/display/intel_opregion.c | 7 ++-
> 2 files changed, 29 insertions(+), 22 deletions(-)
>
> diff --git a/drivers/gpu/drm/i915/display/intel_bios.c b/drivers/gpu/drm/i915/display/intel_bios.c
> index 736499a6e2c7..cbfbc56ff5b2 100644
> --- a/drivers/gpu/drm/i915/display/intel_bios.c
> +++ b/drivers/gpu/drm/i915/display/intel_bios.c
> @@ -2930,12 +2930,11 @@ static u32 intel_spi_read(struct intel_uncore *uncore, u32 offset)
> return intel_uncore_read(uncore, PRIMARY_SPI_TRIGGER);
> }
>
> -static struct vbt_header *spi_oprom_get_vbt(struct drm_i915_private *i915)
> +static struct vbt_header *spi_oprom_get_vbt(struct drm_i915_private *i915, u16 *vbt_size)
> {
> u32 count, data, found, store = 0;
> u32 static_region, oprom_offset;
> u32 oprom_size = 0x200000;
> - u16 vbt_size;
> u32 *vbt;
>
> static_region = intel_uncore_read(&i915->uncore, SPI_STATIC_REGIONS);
> @@ -2957,18 +2956,18 @@ static struct vbt_header *spi_oprom_get_vbt(struct drm_i915_private *i915)
> goto err_not_found;
>
> /* Get VBT size and allocate space for the VBT */
> - vbt_size = intel_spi_read(&i915->uncore,
> + *vbt_size = intel_spi_read(&i915->uncore,
> found + offsetof(struct vbt_header, vbt_size));
> - vbt_size &= 0xffff;
> + *vbt_size &= 0xffff;
>
> - vbt = kzalloc(round_up(vbt_size, 4), GFP_KERNEL);
> + vbt = kzalloc(round_up(*vbt_size, 4), GFP_KERNEL);
> if (!vbt)
> goto err_not_found;
>
> - for (count = 0; count < vbt_size; count += 4)
> + for (count = 0; count < *vbt_size; count += 4)
> *(vbt + store++) = intel_spi_read(&i915->uncore, found + count);
>
> - if (!intel_bios_is_valid_vbt(vbt, vbt_size))
> + if (!intel_bios_is_valid_vbt(vbt, *vbt_size))
> goto err_free_vbt;
>
> drm_dbg_kms(&i915->drm, "Found valid VBT in SPI flash\n");
> @@ -2977,16 +2976,16 @@ static struct vbt_header *spi_oprom_get_vbt(struct drm_i915_private *i915)
>
> err_free_vbt:
> kfree(vbt);
> + *vbt_size = 0;
> err_not_found:
> return NULL;
> }
>
> -static struct vbt_header *oprom_get_vbt(struct drm_i915_private *i915)
> +static struct vbt_header *oprom_get_vbt(struct drm_i915_private *i915, u16 *vbt_size)
> {
> struct pci_dev *pdev = to_pci_dev(i915->drm.dev);
> void __iomem *p = NULL, *oprom;
> struct vbt_header *vbt;
> - u16 vbt_size;
> size_t i, size;
>
> oprom = pci_map_rom(pdev, &size);
> @@ -3011,21 +3010,21 @@ static struct vbt_header *oprom_get_vbt(struct drm_i915_private *i915)
> goto err_unmap_oprom;
> }
>
> - vbt_size = ioread16(p + offsetof(struct vbt_header, vbt_size));
> - if (vbt_size > size) {
> + *vbt_size = ioread16(p + offsetof(struct vbt_header, vbt_size));
> + if (*vbt_size > size) {
> drm_dbg(&i915->drm,
> - "VBT incomplete (vbt_size overflows)\n");
> + "VBT incomplete (*vbt_size overflows)\n");
> goto err_unmap_oprom;
> }
>
> /* The rest will be validated by intel_bios_is_valid_vbt() */
> - vbt = kmalloc(vbt_size, GFP_KERNEL);
> + vbt = kmalloc(*vbt_size, GFP_KERNEL);
> if (!vbt)
> goto err_unmap_oprom;
>
> - memcpy_fromio(vbt, p, vbt_size);
> + memcpy_fromio(vbt, p, *vbt_size);
>
> - if (!intel_bios_is_valid_vbt(vbt, vbt_size))
> + if (!intel_bios_is_valid_vbt(vbt, *vbt_size))
> goto err_free_vbt;
>
> pci_unmap_rom(pdev, oprom);
> @@ -3036,6 +3035,7 @@ static struct vbt_header *oprom_get_vbt(struct drm_i915_private *i915)
>
> err_free_vbt:
> kfree(vbt);
> + *vbt_size = 0;
> err_unmap_oprom:
> pci_unmap_rom(pdev, oprom);
>
> @@ -3052,8 +3052,10 @@ static struct vbt_header *oprom_get_vbt(struct drm_i915_private *i915)
> */
> void intel_bios_init(struct drm_i915_private *i915)
> {
> + struct intel_opregion *opregion = &i915->display.opregion;
> const struct vbt_header *vbt = i915->display.opregion.vbt;
> struct vbt_header *oprom_vbt = NULL;
> + u16 vbt_size;
> const struct bdb_header *bdb;
>
> INIT_LIST_HEAD(&i915->display.vbt.display_devices);
> @@ -3072,13 +3074,15 @@ void intel_bios_init(struct drm_i915_private *i915)
> * PCI mapping
> */
> if (!vbt && IS_DGFX(i915)) {
> - oprom_vbt = spi_oprom_get_vbt(i915);
> - vbt = oprom_vbt;
> + oprom_vbt = spi_oprom_get_vbt(i915, &vbt_size);
> + opregion->vbt = vbt = oprom_vbt;
> + opregion->vbt_size = (u32)vbt_size;
> }
>
> if (!vbt) {
> - oprom_vbt = oprom_get_vbt(i915);
> - vbt = oprom_vbt;
> + oprom_vbt = oprom_get_vbt(i915, &vbt_size);
> + opregion->vbt = vbt = oprom_vbt;
> + opregion->vbt_size = (u32)vbt_size;
> }
>
> if (!vbt)
> @@ -3111,8 +3115,6 @@ void intel_bios_init(struct drm_i915_private *i915)
> /* Further processing on pre-parsed or generated child device data */
> parse_sdvo_device_mapping(i915);
> parse_ddi_ports(i915);
> -
> - kfree(oprom_vbt);
> }
>
> static void intel_bios_init_panel(struct drm_i915_private *i915,
> diff --git a/drivers/gpu/drm/i915/display/intel_opregion.c b/drivers/gpu/drm/i915/display/intel_opregion.c
> index 1ce785db6a5e..20b2160e9d0e 100644
> --- a/drivers/gpu/drm/i915/display/intel_opregion.c
> +++ b/drivers/gpu/drm/i915/display/intel_opregion.c
> @@ -1244,8 +1244,13 @@ void intel_opregion_cleanup(struct drm_i915_private *i915)
> {
> struct intel_opregion *opregion = &i915->display.opregion;
>
> - if (!opregion->header)
> + if (!opregion->header) {
> + if (opregion->vbt) {
> + kfree(opregion->vbt);
> + opregion->vbt_size = 0;
> + }
> return;
> + }
>
> /* just clear all opregion memory pointers now */
> memunmap(opregion->header);
> --
> 2.34.1
--
Ville Syrjälä
Intel
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