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authorLinus Torvalds <[email protected]>2025-07-31 02:26:49 +0000
committerLinus Torvalds <[email protected]>2025-07-31 02:26:49 +0000
commit260f6f4fda93c8485c8037865c941b42b9cba5d2 (patch)
tree587a0ea46d3351f63250d19860b01da8217ac774 /drivers/gpu/drm/msm/msm_iommu.c
parentMerge tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm (diff)
parentMerge tag 'drm-misc-next-fixes-2025-07-24' of https://gitlab.freedesktop.org/... (diff)
downloadkernel-260f6f4fda93c8485c8037865c941b42b9cba5d2.tar.gz
kernel-260f6f4fda93c8485c8037865c941b42b9cba5d2.zip
Merge tag 'drm-next-2025-07-30' of https://gitlab.freedesktop.org/drm/kernel
Pull drm updates from Dave Airlie: "Highlights: - Intel xe enable Panthor Lake, started adding WildCat Lake - amdgpu has a bunch of reset improvments along with the usual IP updates - msm got VM_BIND support which is important for vulkan sparse memory - more drm_panic users - gpusvm common code to handle a bunch of core SVM work outside drivers. Detail summary: Changes outside drm subdirectory: - 'shrink_shmem_memory()' for better shmem/hibernate interaction - Rust support infrastructure: - make ETIMEDOUT available - add size constants up to SZ_2G - add DMA coherent allocation bindings - mtd driver for Intel GPU non-volatile storage - i2c designware quirk for Intel xe core: - atomic helpers: tune enable/disable sequences - add task info to wedge API - refactor EDID quirks - connector: move HDR sink to drm_display_info - fourcc: half-float and 32-bit float formats - mode_config: pass format info to simplify dma-buf: - heaps: Give CMA heap a stable name ci: - add device tree validation and kunit displayport: - change AUX DPCD access probe address - add quirk for DPCD probe - add panel replay definitions - backlight control helpers fbdev: - make CONFIG_FIRMWARE_EDID available on all arches fence: - fix UAF issues format-helper: - improve tests gpusvm: - introduce devmem only flag for allocation - add timeslicing support to GPU SVM ttm: - improve eviction sched: - tracing improvements - kunit improvements - memory leak fixes - reset handling improvements color mgmt: - add hardware gamma LUT handling helpers bridge: - add destroy hook - switch to reference counted drm_bridge allocations - tc358767: convert to devm_drm_bridge_alloc - improve CEC handling panel: - switch to reference counter drm_panel allocations - fwnode panel lookup - Huiling hl055fhv028c support - Raspberry Pi 7" 720x1280 support - edp: KDC KD116N3730A05, N160JCE-ELL CMN, N116BCJ-EAK - simple: AUO P238HAN01 - st7701: Winstar wf40eswaa6mnn0 - visionox: rm69299-shift - Renesas R61307, Renesas R69328 support - DJN HX83112B hdmi: - add CEC handling - YUV420 output support xe: - WildCat Lake support - Enable PanthorLake by default - mark BMG as SRIOV capable - update firmware recommendations - Expose media OA units - aux-bux support for non-volatile memory - MTD intel-dg driver for non-volatile memory - Expose fan control and voltage regulator in sysfs - restructure migration for multi-device - Restore GuC submit UAF fix - make GEM shrinker drm managed - SRIOV VF Post-migration recovery of GGTT nodes - W/A additions/reworks - Prefetch support for svm ranges - Don't allocate managed BO for each policy change - HWMON fixes for BMG - Create LRC BO without VM - PCI ID updates - make SLPC debugfs files optional - rework eviction rejection of bound external BOs - consolidate PAT programming logic for pre/post Xe2 - init changes for flicker-free boot - Enable GuC Dynamic Inhibit Context switch i915: - drm_panic support for i915/xe - initial flip queue off by default for LNL/PNL - Wildcat Lake Display support - Support for DSC fractional link bpp - Support for simultaneous Panel Replay and Adaptive sync - Support for PTL+ double buffer LUT - initial PIPEDMC event handling - drm_panel_follower support - DPLL interface renames - allocate struct intel_display dynamically - flip queue preperation - abstract DRAM detection better - avoid GuC scheduling stalls - remove DG1 force probe requirement - fix MEI interrupt handler on RT kernels - use backlight control helpers for eDP - more shared display code refactoring amdgpu: - add userq slot to INFO ioctl - SR-IOV hibernation support - Suspend improvements - Backlight improvements - Use scaling for non-native eDP modes - cleaner shader updates for GC 9.x - Remove fence slab - SDMA fw checks for userq support - RAS updates - DMCUB updates - DP tunneling fixes - Display idle D3 support - Per queue reset improvements - initial smartmux support amdkfd: - enable KFD on loongarch - mtype fix for ext coherent system memory radeon: - CS validation additional GL extensions - drop console lock during suspend/resume - bump driver version msm: - VM BIND support - CI: infrastructure updates - UBWC single source of truth - decouple GPU and KMS support - DP: rework I/O accessors - DPU: SM8750 support - DSI: SM8750 support - GPU: X1-45 support and speedbin support for X1-85 - MDSS: SM8750 support nova: - register! macro improvements - DMA object abstraction - VBIOS parser + fwsec lookup - sysmem flush page support - falcon: generic falcon boot code and HAL - FWSEC-FRTS: fb setup and load/execute ivpu: - Add Wildcat Lake support - Add turbo flag ast: - improve hardware generations implementation imx: - IMX8qxq Display Controller support lima: - Rockchip RK3528 GPU support nouveau: - fence handling cleanup panfrost: - MT8370 support - bo labeling - 64-bit register access qaic: - add RAS support rockchip: - convert inno_hdmi to a bridge rz-du: - add RZ/V2H(P) support - MIPI-DSI DCS support sitronix: - ST7567 support sun4i: - add H616 support tidss: - add TI AM62L support - AM65x OLDI bridge support bochs: - drm panic support vkms: - YUV and R* format support - use faux device vmwgfx: - fence improvements hyperv: - move out of simple - add drm_panic support" * tag 'drm-next-2025-07-30' of https://gitlab.freedesktop.org/drm/kernel: (1479 commits) drm/tidss: oldi: convert to devm_drm_bridge_alloc() API drm/tidss: encoder: convert to devm_drm_bridge_alloc() drm/amdgpu: move reset support type checks into the caller drm/amdgpu/sdma7: re-emit unprocessed state on ring reset drm/amdgpu/sdma6: re-emit unprocessed state on ring reset drm/amdgpu/sdma5.2: re-emit unprocessed state on ring reset drm/amdgpu/sdma5: re-emit unprocessed state on ring reset drm/amdgpu/gfx12: re-emit unprocessed state on ring reset drm/amdgpu/gfx11: re-emit unprocessed state on ring reset drm/amdgpu/gfx10: re-emit unprocessed state on ring reset drm/amdgpu/gfx9.4.3: re-emit unprocessed state on kcq reset drm/amdgpu/gfx9: re-emit unprocessed state on kcq reset drm/amdgpu: Add WARN_ON to the resource clear function drm/amd/pm: Use cached metrics data on SMUv13.0.6 drm/amd/pm: Use cached data for min/max clocks gpu: nova-core: fix bounds check in PmuLookupTableEntry::new drm/amdgpu: Replace HQD terminology with slots naming drm/amdgpu: Add user queue instance count in HW IP info drm/amd/amdgpu: Add helper functions for isp buffers drm/amd/amdgpu: Initialize swnode for ISP MFD device ...
Diffstat (limited to 'drivers/gpu/drm/msm/msm_iommu.c')
-rw-r--r--drivers/gpu/drm/msm/msm_iommu.c302
1 files changed, 293 insertions, 9 deletions
diff --git a/drivers/gpu/drm/msm/msm_iommu.c b/drivers/gpu/drm/msm/msm_iommu.c
index 739ce2c283a4..55c29f49b788 100644
--- a/drivers/gpu/drm/msm/msm_iommu.c
+++ b/drivers/gpu/drm/msm/msm_iommu.c
@@ -6,13 +6,18 @@
#include <linux/adreno-smmu-priv.h>
#include <linux/io-pgtable.h>
+#include <linux/kmemleak.h>
#include "msm_drv.h"
+#include "msm_gpu_trace.h"
#include "msm_mmu.h"
struct msm_iommu {
struct msm_mmu base;
struct iommu_domain *domain;
atomic_t pagetables;
+ struct page *prr_page;
+
+ struct kmem_cache *pt_cache;
};
#define to_msm_iommu(x) container_of(x, struct msm_iommu, base)
@@ -26,6 +31,9 @@ struct msm_iommu_pagetable {
unsigned long pgsize_bitmap; /* Bitmap of page sizes in use */
phys_addr_t ttbr;
u32 asid;
+
+ /** @root_page_table: Stores the root page table pointer. */
+ void *root_page_table;
};
static struct msm_iommu_pagetable *to_pagetable(struct msm_mmu *mmu)
{
@@ -93,15 +101,24 @@ static int msm_iommu_pagetable_unmap(struct msm_mmu *mmu, u64 iova,
{
struct msm_iommu_pagetable *pagetable = to_pagetable(mmu);
struct io_pgtable_ops *ops = pagetable->pgtbl_ops;
+ int ret = 0;
while (size) {
- size_t unmapped, pgsize, count;
+ size_t pgsize, count;
+ ssize_t unmapped;
pgsize = calc_pgsize(pagetable, iova, iova, size, &count);
unmapped = ops->unmap_pages(ops, iova, pgsize, count, NULL);
- if (!unmapped)
- break;
+ if (unmapped <= 0) {
+ ret = -EINVAL;
+ /*
+ * Continue attempting to unamp the remained of the
+ * range, so we don't end up with some dangling
+ * mapped pages
+ */
+ unmapped = PAGE_SIZE;
+ }
iova += unmapped;
size -= unmapped;
@@ -109,11 +126,42 @@ static int msm_iommu_pagetable_unmap(struct msm_mmu *mmu, u64 iova,
iommu_flush_iotlb_all(to_msm_iommu(pagetable->parent)->domain);
- return (size == 0) ? 0 : -EINVAL;
+ return ret;
+}
+
+static int msm_iommu_pagetable_map_prr(struct msm_mmu *mmu, u64 iova, size_t len, int prot)
+{
+ struct msm_iommu_pagetable *pagetable = to_pagetable(mmu);
+ struct io_pgtable_ops *ops = pagetable->pgtbl_ops;
+ struct msm_iommu *iommu = to_msm_iommu(pagetable->parent);
+ phys_addr_t phys = page_to_phys(iommu->prr_page);
+ u64 addr = iova;
+
+ while (len) {
+ size_t mapped = 0;
+ size_t size = PAGE_SIZE;
+ int ret;
+
+ ret = ops->map_pages(ops, addr, phys, size, 1, prot, GFP_KERNEL, &mapped);
+
+ /* map_pages could fail after mapping some of the pages,
+ * so update the counters before error handling.
+ */
+ addr += mapped;
+ len -= mapped;
+
+ if (ret) {
+ msm_iommu_pagetable_unmap(mmu, iova, addr - iova);
+ return -EINVAL;
+ }
+ }
+
+ return 0;
}
static int msm_iommu_pagetable_map(struct msm_mmu *mmu, u64 iova,
- struct sg_table *sgt, size_t len, int prot)
+ struct sg_table *sgt, size_t off, size_t len,
+ int prot)
{
struct msm_iommu_pagetable *pagetable = to_pagetable(mmu);
struct io_pgtable_ops *ops = pagetable->pgtbl_ops;
@@ -121,10 +169,26 @@ static int msm_iommu_pagetable_map(struct msm_mmu *mmu, u64 iova,
u64 addr = iova;
unsigned int i;
+ if (!sgt)
+ return msm_iommu_pagetable_map_prr(mmu, iova, len, prot);
+
for_each_sgtable_sg(sgt, sg, i) {
size_t size = sg->length;
phys_addr_t phys = sg_phys(sg);
+ if (!len)
+ break;
+
+ if (size <= off) {
+ off -= size;
+ continue;
+ }
+
+ phys += off;
+ size -= off;
+ size = min_t(size_t, size, len);
+ off = 0;
+
while (size) {
size_t pgsize, count, mapped = 0;
int ret;
@@ -140,6 +204,7 @@ static int msm_iommu_pagetable_map(struct msm_mmu *mmu, u64 iova,
phys += mapped;
addr += mapped;
size -= mapped;
+ len -= mapped;
if (ret) {
msm_iommu_pagetable_unmap(mmu, iova, addr - iova);
@@ -162,9 +227,16 @@ static void msm_iommu_pagetable_destroy(struct msm_mmu *mmu)
* If this is the last attached pagetable for the parent,
* disable TTBR0 in the arm-smmu driver
*/
- if (atomic_dec_return(&iommu->pagetables) == 0)
+ if (atomic_dec_return(&iommu->pagetables) == 0) {
adreno_smmu->set_ttbr0_cfg(adreno_smmu->cookie, NULL);
+ if (adreno_smmu->set_prr_bit) {
+ adreno_smmu->set_prr_bit(adreno_smmu->cookie, false);
+ __free_page(iommu->prr_page);
+ iommu->prr_page = NULL;
+ }
+ }
+
free_io_pgtable_ops(pagetable->pgtbl_ops);
kfree(pagetable);
}
@@ -217,7 +289,148 @@ msm_iommu_pagetable_walk(struct msm_mmu *mmu, unsigned long iova, uint64_t ptes[
return 0;
}
+static void
+msm_iommu_pagetable_prealloc_count(struct msm_mmu *mmu, struct msm_mmu_prealloc *p,
+ uint64_t iova, size_t len)
+{
+ u64 pt_count;
+
+ /*
+ * L1, L2 and L3 page tables.
+ *
+ * We could optimize L3 allocation by iterating over the sgt and merging
+ * 2M contiguous blocks, but it's simpler to over-provision and return
+ * the pages if they're not used.
+ *
+ * The first level descriptor (v8 / v7-lpae page table format) encodes
+ * 30 bits of address. The second level encodes 29. For the 3rd it is
+ * 39.
+ *
+ * https://developer.arm.com/documentation/ddi0406/c/System-Level-Architecture/Virtual-Memory-System-Architecture--VMSA-/Long-descriptor-translation-table-format/Long-descriptor-translation-table-format-descriptors?lang=en#BEIHEFFB
+ */
+ pt_count = ((ALIGN(iova + len, 1ull << 39) - ALIGN_DOWN(iova, 1ull << 39)) >> 39) +
+ ((ALIGN(iova + len, 1ull << 30) - ALIGN_DOWN(iova, 1ull << 30)) >> 30) +
+ ((ALIGN(iova + len, 1ull << 21) - ALIGN_DOWN(iova, 1ull << 21)) >> 21);
+
+ p->count += pt_count;
+}
+
+static struct kmem_cache *
+get_pt_cache(struct msm_mmu *mmu)
+{
+ struct msm_iommu_pagetable *pagetable = to_pagetable(mmu);
+ return to_msm_iommu(pagetable->parent)->pt_cache;
+}
+
+static int
+msm_iommu_pagetable_prealloc_allocate(struct msm_mmu *mmu, struct msm_mmu_prealloc *p)
+{
+ struct kmem_cache *pt_cache = get_pt_cache(mmu);
+ int ret;
+
+ p->pages = kvmalloc_array(p->count, sizeof(p->pages), GFP_KERNEL);
+ if (!p->pages)
+ return -ENOMEM;
+
+ ret = kmem_cache_alloc_bulk(pt_cache, GFP_KERNEL, p->count, p->pages);
+ if (ret != p->count) {
+ p->count = ret;
+ return -ENOMEM;
+ }
+
+ return 0;
+}
+
+static void
+msm_iommu_pagetable_prealloc_cleanup(struct msm_mmu *mmu, struct msm_mmu_prealloc *p)
+{
+ struct kmem_cache *pt_cache = get_pt_cache(mmu);
+ uint32_t remaining_pt_count = p->count - p->ptr;
+
+ if (p->count > 0)
+ trace_msm_mmu_prealloc_cleanup(p->count, remaining_pt_count);
+
+ kmem_cache_free_bulk(pt_cache, remaining_pt_count, &p->pages[p->ptr]);
+ kvfree(p->pages);
+}
+
+/**
+ * alloc_pt() - Custom page table allocator
+ * @cookie: Cookie passed at page table allocation time.
+ * @size: Size of the page table. This size should be fixed,
+ * and determined at creation time based on the granule size.
+ * @gfp: GFP flags.
+ *
+ * We want a custom allocator so we can use a cache for page table
+ * allocations and amortize the cost of the over-reservation that's
+ * done to allow asynchronous VM operations.
+ *
+ * Return: non-NULL on success, NULL if the allocation failed for any
+ * reason.
+ */
+static void *
+msm_iommu_pagetable_alloc_pt(void *cookie, size_t size, gfp_t gfp)
+{
+ struct msm_iommu_pagetable *pagetable = cookie;
+ struct msm_mmu_prealloc *p = pagetable->base.prealloc;
+ void *page;
+
+ /* Allocation of the root page table happening during init. */
+ if (unlikely(!pagetable->root_page_table)) {
+ struct page *p;
+
+ p = alloc_pages_node(dev_to_node(pagetable->iommu_dev),
+ gfp | __GFP_ZERO, get_order(size));
+ page = p ? page_address(p) : NULL;
+ pagetable->root_page_table = page;
+ return page;
+ }
+
+ if (WARN_ON(!p) || WARN_ON(p->ptr >= p->count))
+ return NULL;
+
+ page = p->pages[p->ptr++];
+ memset(page, 0, size);
+
+ /*
+ * Page table entries don't use virtual addresses, which trips out
+ * kmemleak. kmemleak_alloc_phys() might work, but physical addresses
+ * are mixed with other fields, and I fear kmemleak won't detect that
+ * either.
+ *
+ * Let's just ignore memory passed to the page-table driver for now.
+ */
+ kmemleak_ignore(page);
+
+ return page;
+}
+
+
+/**
+ * free_pt() - Custom page table free function
+ * @cookie: Cookie passed at page table allocation time.
+ * @data: Page table to free.
+ * @size: Size of the page table. This size should be fixed,
+ * and determined at creation time based on the granule size.
+ */
+static void
+msm_iommu_pagetable_free_pt(void *cookie, void *data, size_t size)
+{
+ struct msm_iommu_pagetable *pagetable = cookie;
+
+ if (unlikely(pagetable->root_page_table == data)) {
+ free_pages((unsigned long)data, get_order(size));
+ pagetable->root_page_table = NULL;
+ return;
+ }
+
+ kmem_cache_free(get_pt_cache(&pagetable->base), data);
+}
+
static const struct msm_mmu_funcs pagetable_funcs = {
+ .prealloc_count = msm_iommu_pagetable_prealloc_count,
+ .prealloc_allocate = msm_iommu_pagetable_prealloc_allocate,
+ .prealloc_cleanup = msm_iommu_pagetable_prealloc_cleanup,
.map = msm_iommu_pagetable_map,
.unmap = msm_iommu_pagetable_unmap,
.destroy = msm_iommu_pagetable_destroy,
@@ -268,7 +481,18 @@ static const struct iommu_flush_ops tlb_ops = {
static int msm_gpu_fault_handler(struct iommu_domain *domain, struct device *dev,
unsigned long iova, int flags, void *arg);
-struct msm_mmu *msm_iommu_pagetable_create(struct msm_mmu *parent)
+static size_t get_tblsz(const struct io_pgtable_cfg *cfg)
+{
+ int pg_shift, bits_per_level;
+
+ pg_shift = __ffs(cfg->pgsize_bitmap);
+ /* arm_lpae_iopte is u64: */
+ bits_per_level = pg_shift - ilog2(sizeof(u64));
+
+ return sizeof(u64) << bits_per_level;
+}
+
+struct msm_mmu *msm_iommu_pagetable_create(struct msm_mmu *parent, bool kernel_managed)
{
struct adreno_smmu_priv *adreno_smmu = dev_get_drvdata(parent->dev);
struct msm_iommu *iommu = to_msm_iommu(parent);
@@ -302,6 +526,36 @@ struct msm_mmu *msm_iommu_pagetable_create(struct msm_mmu *parent)
ttbr0_cfg.quirks &= ~IO_PGTABLE_QUIRK_ARM_TTBR1;
ttbr0_cfg.tlb = &tlb_ops;
+ if (!kernel_managed) {
+ ttbr0_cfg.quirks |= IO_PGTABLE_QUIRK_NO_WARN;
+
+ /*
+ * With userspace managed VM (aka VM_BIND), we need to pre-
+ * allocate pages ahead of time for map/unmap operations,
+ * handing them to io-pgtable via custom alloc/free ops as
+ * needed:
+ */
+ ttbr0_cfg.alloc = msm_iommu_pagetable_alloc_pt;
+ ttbr0_cfg.free = msm_iommu_pagetable_free_pt;
+
+ /*
+ * Restrict to single page granules. Otherwise we may run
+ * into a situation where userspace wants to unmap/remap
+ * only a part of a larger block mapping, which is not
+ * possible without unmapping the entire block. Which in
+ * turn could cause faults if the GPU is accessing other
+ * parts of the block mapping.
+ *
+ * Note that prior to commit 33729a5fc0ca ("iommu/io-pgtable-arm:
+ * Remove split on unmap behavior)" this was handled in
+ * io-pgtable-arm. But this apparently does not work
+ * correctly on SMMUv3.
+ */
+ WARN_ON(!(ttbr0_cfg.pgsize_bitmap & PAGE_SIZE));
+ ttbr0_cfg.pgsize_bitmap = PAGE_SIZE;
+ }
+
+ pagetable->iommu_dev = ttbr1_cfg->iommu_dev;
pagetable->pgtbl_ops = alloc_io_pgtable_ops(ARM_64_LPAE_S1,
&ttbr0_cfg, pagetable);
@@ -321,12 +575,30 @@ struct msm_mmu *msm_iommu_pagetable_create(struct msm_mmu *parent)
kfree(pagetable);
return ERR_PTR(ret);
}
+
+ BUG_ON(iommu->prr_page);
+ if (adreno_smmu->set_prr_bit) {
+ /*
+ * We need a zero'd page for two reasons:
+ *
+ * 1) Reserve a known physical address to use when
+ * mapping NULL / sparsely resident regions
+ * 2) Read back zero
+ *
+ * It appears the hw drops writes to the PRR region
+ * on the floor, but reads actually return whatever
+ * is in the PRR page.
+ */
+ iommu->prr_page = alloc_page(GFP_KERNEL | __GFP_ZERO);
+ adreno_smmu->set_prr_addr(adreno_smmu->cookie,
+ page_to_phys(iommu->prr_page));
+ adreno_smmu->set_prr_bit(adreno_smmu->cookie, true);
+ }
}
/* Needed later for TLB flush */
pagetable->parent = parent;
pagetable->tlb = ttbr1_cfg->tlb;
- pagetable->iommu_dev = ttbr1_cfg->iommu_dev;
pagetable->pgsize_bitmap = ttbr0_cfg.pgsize_bitmap;
pagetable->ttbr = ttbr0_cfg.arm_lpae_s1_cfg.ttbr;
@@ -388,11 +660,14 @@ static void msm_iommu_detach(struct msm_mmu *mmu)
}
static int msm_iommu_map(struct msm_mmu *mmu, uint64_t iova,
- struct sg_table *sgt, size_t len, int prot)
+ struct sg_table *sgt, size_t off, size_t len,
+ int prot)
{
struct msm_iommu *iommu = to_msm_iommu(mmu);
size_t ret;
+ WARN_ON(off != 0);
+
/* The arm-smmu driver expects the addresses to be sign extended */
if (iova & BIT_ULL(48))
iova |= GENMASK_ULL(63, 49);
@@ -419,6 +694,7 @@ static void msm_iommu_destroy(struct msm_mmu *mmu)
{
struct msm_iommu *iommu = to_msm_iommu(mmu);
iommu_domain_free(iommu->domain);
+ kmem_cache_destroy(iommu->pt_cache);
kfree(iommu);
}
@@ -492,6 +768,14 @@ struct msm_mmu *msm_iommu_gpu_new(struct device *dev, struct msm_gpu *gpu, unsig
return mmu;
iommu = to_msm_iommu(mmu);
+ if (adreno_smmu && adreno_smmu->cookie) {
+ const struct io_pgtable_cfg *cfg =
+ adreno_smmu->get_ttbr1_cfg(adreno_smmu->cookie);
+ size_t tblsz = get_tblsz(cfg);
+
+ iommu->pt_cache =
+ kmem_cache_create("msm-mmu-pt", tblsz, tblsz, 0, NULL);
+ }
iommu_set_fault_handler(iommu->domain, msm_gpu_fault_handler, iommu);
/* Enable stall on iommu fault: */