Re: [Intel-gfx] [PATCH 03/19] drm/i915: Create stolen memory region from local memory

On 12/04/2021 10:05, Matthew Auld wrote:

From: CQ Tang cq.tang@intel.com

Add "REGION_STOLEN" device info to dg1, create stolen memory region from upper portion of local device memory, starting from DSMBASE.

v2: - s/drm_info/drm_dbg; userspace likely doesn't care about stolen. - mem->type is only setup after the region probe, so setting the name as stolen-local or stolen-system based on this value won't work. Split system vs local stolen setup to fix this. - kill all the region->devmem/is_devmem stuff. We already differentiate the different types of stolen so such things shouldn't be needed anymore.

Signed-off-by: CQ Tang cq.tang@intel.com Signed-off-by: Matthew Auld matthew.auld@intel.com

---

drivers/gpu/drm/i915/gem/i915_gem_stolen.c | 99 +++++++++++++++++++--- drivers/gpu/drm/i915/gem/i915_gem_stolen.h | 3 + drivers/gpu/drm/i915/i915_pci.c | 2 +- drivers/gpu/drm/i915/i915_reg.h | 1 + drivers/gpu/drm/i915/intel_memory_region.c | 6 ++ drivers/gpu/drm/i915/intel_memory_region.h | 5 +- 6 files changed, 102 insertions(+), 14 deletions(-)

diff --git a/drivers/gpu/drm/i915/gem/i915_gem_stolen.c b/drivers/gpu/drm/i915/gem/i915_gem_stolen.c index b0597de206de..56dd58bef5ee 100644 --- a/drivers/gpu/drm/i915/gem/i915_gem_stolen.c +++ b/drivers/gpu/drm/i915/gem/i915_gem_stolen.c @@ -10,6 +10,7 @@ #include <drm/drm_mm.h> #include <drm/i915_drm.h>

+#include "gem/i915_gem_lmem.h" #include "gem/i915_gem_region.h" #include "i915_drv.h" #include "i915_gem_stolen.h" @@ -121,6 +122,14 @@ static int i915_adjust_stolen(struct drm_i915_private *i915, } }

• /*

• * With device local memory, we don't need to check the address range,
  

• * this is device memory physical address, could overlap with system
  

• * memory.
  

• */
  

• if (HAS_LMEM(i915))

• return 0;
  

• /*
  • Verify that nothing else uses this physical address. Stolen
  • memory should be reserved by the BIOS and hidden from the

@@ -374,8 +383,9 @@ static void icl_get_stolen_reserved(struct drm_i915_private *i915, } }

-static int i915_gem_init_stolen(struct drm_i915_private *i915) +static int i915_gem_init_stolen(struct intel_memory_region *mem) {

• struct drm_i915_private *i915 = mem->i915; struct intel_uncore *uncore = &i915->uncore; resource_size_t reserved_base, stolen_top; resource_size_t reserved_total, reserved_size;

@@ -396,10 +406,10 @@ static int i915_gem_init_stolen(struct drm_i915_private *i915) return 0; }

• if (resource_size(&intel_graphics_stolen_res) == 0)

• if (resource_size(&mem->region) == 0) return 0;

• i915->dsm = intel_graphics_stolen_res;

• i915->dsm = mem->region;

  if (i915_adjust_stolen(i915, &i915->dsm)) return 0;

@@ -684,23 +694,36 @@ static int _i915_gem_object_stolen_init(struct intel_memory_region *mem, return ret; }

+struct intel_memory_region *i915_stolen_region(struct drm_i915_private *i915) +{

• if (HAS_LMEM(i915))

• return i915->mm.regions[INTEL_REGION_STOLEN_LMEM];
  

• return i915->mm.regions[INTEL_REGION_STOLEN_SMEM];

+}

Could be a bikeshedding comment only - especially since I think this path gets very little used at runtime so it is most likely pointless to fiddle with it, but it just strikes me a bit not fully elegant to do:

i915_gem_object_create_stolen -> i915_gem_object_create_region -> i915_stolen_region

And end up in here, when alternative could be at driver init:

i915->stolen_region_id = HAS_LMEM() ? ... : ...;

i915_gem_object_create_stolen -> i915_gem_object_create_region(i915->mm.regions[i915->stolen_region_id]);

Or pointer to region. Would avoid having to export i915_stolen_region as well.

Or is i915->dsm already the right thing? Because..

• struct drm_i915_gem_object * i915_gem_object_create_stolen(struct drm_i915_private *i915, resource_size_t size) {

• return i915_gem_object_create_region(i915->mm.regions[INTEL_REGION_STOLEN_SMEM],

• return i915_gem_object_create_region(i915_stolen_region(i915), size, I915_BO_ALLOC_CONTIGUOUS); }

  static int init_stolen(struct intel_memory_region *mem) {

• intel_memory_region_set_name(mem, "stolen");

• if (HAS_LMEM(mem->i915)) {

• if (!io_mapping_init_wc(&mem->iomap,
  

• 			mem->io_start,
  

• 			resource_size(&mem->region)))
  

• 	return -EIO;
  

• }

  /*

  • Initialise stolen early so that we may reserve preallocated
  • objects for the BIOS to KMS transition.

  */

• return i915_gem_init_stolen(mem->i915);

• return i915_gem_init_stolen(mem);

... I find the mem region init paths a bit convoluted, stolen especially, and struggle to figure it out every time.

For instance we have i915_region_stolen_ops shared between system and local stolen. But then shared vfuncs branch depending on system vs stolen?

i915_gem_init_stolen is shared - but which parts of it are relevant for local stolen?

}

static void release_stolen(struct intel_memory_region *mem) @@ -714,13 +737,65 @@ static const struct intel_memory_region_ops i915_region_stolen_ops = { .init_object = _i915_gem_object_stolen_init, };

+static struct intel_memory_region * +setup_lmem_stolen(struct drm_i915_private *i915) +{

• struct intel_uncore *uncore = &i915->uncore;
• struct pci_dev *pdev = i915->drm.pdev;
• struct intel_memory_region *mem;
• resource_size_t io_start;
• resource_size_t lmem_size;
• u64 lmem_base;
• if (!IS_DGFX(i915))

• return ERR_PTR(-ENODEV);
  

• lmem_base = intel_uncore_read64(uncore, GEN12_DSMBASE);
• lmem_size = pci_resource_len(pdev, 2) - lmem_base;
• io_start = pci_resource_start(pdev, 2) + lmem_base;
• mem = intel_memory_region_create(i915, lmem_base, lmem_size,

• 			 I915_GTT_PAGE_SIZE_4K, io_start,
  

• 			 &i915_region_stolen_ops);
  

• if (IS_ERR(mem))

• return mem;
  

• drm_dbg(&i915->drm, "Stolen Local memory: %pR\n", &mem->region);
• drm_dbg(&i915->drm, "Stolen Local memory IO start: %pa\n",

• &mem->io_start);
  

Could these messages be consolidated with the system stolen ones (i915_gem_setup_stolen?) and based off the memory_region data printed from common i915_gem_stolen_setup?

• intel_memory_region_set_name(mem, "stolen-local");
• return mem;

+}

+static struct intel_memory_region*

Space before asterisk.

+setup_smem_stolen(struct drm_i915_private *i915) +{

• struct intel_memory_region *mem;
• mem = intel_memory_region_create(i915,

• 			 intel_graphics_stolen_res.start,
  

• 			 resource_size(&intel_graphics_stolen_res),
  

• 			 PAGE_SIZE, 0,
  

• 			 &i915_region_stolen_ops);
  

• if (IS_ERR(mem))

• return mem;
  

• intel_memory_region_set_name(mem, "stolen-system");

I assume this name, although changed from the current ("stolen"), is not exported anywhere to matter?

• return mem;

+}

• struct intel_memory_region *i915_gem_stolen_setup(struct drm_i915_private *i915) {

• return intel_memory_region_create(i915,

• 			  intel_graphics_stolen_res.start,
  

• 			  resource_size(&intel_graphics_stolen_res),
  

• 			  PAGE_SIZE, 0,
  

• 			  &i915_region_stolen_ops);
  

• struct intel_memory_region *mem;

• mem = setup_lmem_stolen(i915);

• if (mem == ERR_PTR(-ENODEV))

• mem = setup_smem_stolen(i915);
  

• return mem; }

  struct drm_i915_gem_object *

@@ -728,7 +803,7 @@ i915_gem_object_create_stolen_for_preallocated(struct drm_i915_private *i915, resource_size_t stolen_offset, resource_size_t size) {

• struct intel_memory_region *mem = i915->mm.regions[INTEL_REGION_STOLEN_SMEM];

• struct intel_memory_region *mem = i915_stolen_region(i915); struct drm_i915_gem_object *obj; struct drm_mm_node *stolen; int ret;

diff --git a/drivers/gpu/drm/i915/gem/i915_gem_stolen.h b/drivers/gpu/drm/i915/gem/i915_gem_stolen.h index b03489706796..2d1ce7fec61c 100644 --- a/drivers/gpu/drm/i915/gem/i915_gem_stolen.h +++ b/drivers/gpu/drm/i915/gem/i915_gem_stolen.h @@ -22,6 +22,9 @@ int i915_gem_stolen_insert_node_in_range(struct drm_i915_private *dev_priv, void i915_gem_stolen_remove_node(struct drm_i915_private *dev_priv, struct drm_mm_node *node); struct intel_memory_region *i915_gem_stolen_setup(struct drm_i915_private *i915);

+struct intel_memory_region *i915_stolen_region(struct drm_i915_private *i915);

• struct drm_i915_gem_object * i915_gem_object_create_stolen(struct drm_i915_private *dev_priv, resource_size_t size);

diff --git a/drivers/gpu/drm/i915/i915_pci.c b/drivers/gpu/drm/i915/i915_pci.c index 480553746794..53f5d1e6daef 100644 --- a/drivers/gpu/drm/i915/i915_pci.c +++ b/drivers/gpu/drm/i915/i915_pci.c @@ -906,7 +906,7 @@ static const struct intel_device_info rkl_info = {

#define GEN12_DGFX_FEATURES \ GEN12_FEATURES, \

• .memory_regions = REGION_SMEM | REGION_LMEM, \

• .memory_regions = REGION_SMEM | REGION_LMEM | REGION_STOLEN_LMEM, \ .has_master_unit_irq = 1, \ .has_llc = 0, \ .has_snoop = 1, \

diff --git a/drivers/gpu/drm/i915/i915_reg.h b/drivers/gpu/drm/i915/i915_reg.h index e087bcd21911..4108f2a7ebfa 100644 --- a/drivers/gpu/drm/i915/i915_reg.h +++ b/drivers/gpu/drm/i915/i915_reg.h @@ -12191,6 +12191,7 @@ enum skl_power_gate { #define GEN12_GLOBAL_MOCS(i) _MMIO(0x4000 + (i) * 4) /* Global MOCS regs */

#define GEN12_GSMBASE _MMIO(0x108100) +#define GEN12_DSMBASE _MMIO(0x1080C0)

/* gamt regs */ #define GEN8_L3_LRA_1_GPGPU _MMIO(0x4dd4) diff --git a/drivers/gpu/drm/i915/intel_memory_region.c b/drivers/gpu/drm/i915/intel_memory_region.c index bf837b6bb185..ac90b76a3fa0 100644 --- a/drivers/gpu/drm/i915/intel_memory_region.c +++ b/drivers/gpu/drm/i915/intel_memory_region.c @@ -22,6 +22,10 @@ static const struct { .class = INTEL_MEMORY_STOLEN_SYSTEM, .instance = 0, },

• [INTEL_REGION_STOLEN_LMEM] = {

• .class = INTEL_MEMORY_STOLEN_LOCAL,
  

• .instance = 0,
  

• }, };

  struct intel_memory_region *

@@ -278,6 +282,8 @@ int intel_memory_regions_hw_probe(struct drm_i915_private *i915) case INTEL_MEMORY_SYSTEM: mem = i915_gem_shmem_setup(i915); break;

• case INTEL_MEMORY_STOLEN_LOCAL:
  

• 	fallthrough;
  

  case INTEL_MEMORY_STOLEN_SYSTEM: mem = i915_gem_stolen_setup(i915); break;

diff --git a/drivers/gpu/drm/i915/intel_memory_region.h b/drivers/gpu/drm/i915/intel_memory_region.h index edd49067c8ca..4c8ec15af55f 100644 --- a/drivers/gpu/drm/i915/intel_memory_region.h +++ b/drivers/gpu/drm/i915/intel_memory_region.h @@ -26,18 +26,21 @@ enum intel_memory_type { INTEL_MEMORY_SYSTEM = 0, INTEL_MEMORY_LOCAL, INTEL_MEMORY_STOLEN_SYSTEM,

• INTEL_MEMORY_STOLEN_LOCAL, };

  enum intel_region_id { INTEL_REGION_SMEM = 0, INTEL_REGION_LMEM, INTEL_REGION_STOLEN_SMEM,

• INTEL_REGION_STOLEN_LMEM, INTEL_REGION_UNKNOWN, /* Should be last */ };

  #define REGION_SMEM BIT(INTEL_REGION_SMEM) #define REGION_LMEM BIT(INTEL_REGION_LMEM) #define REGION_STOLEN_SMEM BIT(INTEL_REGION_STOLEN_SMEM)

+#define REGION_STOLEN_LMEM BIT(INTEL_REGION_STOLEN_LMEM)

#define I915_ALLOC_MIN_PAGE_SIZE BIT(0) #define I915_ALLOC_CONTIGUOUS BIT(1) @@ -82,7 +85,7 @@ struct intel_memory_region { u16 type; u16 instance; enum intel_region_id id;

• char name[8];

• char name[16];

  struct list_head reserved;

Regards,

Tvrtko