new file mode 100644
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+// SPDX-License-Identifier: GPL-2.0 or MIT
+/* Copyright 2019 Linaro, Ltd, Rob Herring <robh@kernel.org> */
+/* Copyright 2023 Collabora ltd. */
+
+#include <drm/drm_debugfs.h>
+#include <drm/drm_drv.h>
+#include <drm/drm_exec.h>
+#include <drm/drm_gpuvm.h>
+#include <drm/drm_managed.h>
+#include <drm/gpu_scheduler.h>
+#include <drm/panthor_drm.h>
+
+#include <linux/atomic.h>
+#include <linux/bitfield.h>
+#include <linux/delay.h>
+#include <linux/dma-mapping.h>
+#include <linux/interrupt.h>
+#include <linux/io.h>
+#include <linux/iopoll.h>
+#include <linux/io-pgtable.h>
+#include <linux/iommu.h>
+#include <linux/kmemleak.h>
+#include <linux/platform_device.h>
+#include <linux/pm_runtime.h>
+#include <linux/rwsem.h>
+#include <linux/sched.h>
+#include <linux/shmem_fs.h>
+#include <linux/sizes.h>
+
+#include "panthor_device.h"
+#include "panthor_gem.h"
+#include "panthor_heap.h"
+#include "panthor_mmu.h"
+#include "panthor_regs.h"
+#include "panthor_sched.h"
+
+#define MAX_AS_SLOTS 32
+
+struct panthor_vm;
+
+/**
+ * struct panthor_as_slot - Address space slot
+ */
+struct panthor_as_slot {
+ /** @vm: VM bound to this slot. NULL is no VM is bound. */
+ struct panthor_vm *vm;
+};
+
+/**
+ * struct panthor_mmu - MMU related data
+ */
+struct panthor_mmu {
+ /** @irq: The MMU irq. */
+ struct panthor_irq irq;
+
+ /** @as: Address space related fields.
+ *
+ * The GPU has a limited number of address spaces (AS) slots, forcing
+ * us to re-assign them to re-assign slots on-demand.
+ */
+ struct {
+ /** @slots_lock: Lock protecting access to all other AS fields. */
+ struct mutex slots_lock;
+
+ /** @alloc_mask: Bitmask encoding the allocated slots. */
+ unsigned long alloc_mask;
+
+ /** @faulty_mask: Bitmask encoding the faulty slots. */
+ unsigned long faulty_mask;
+
+ /** @slots: VMs currently bound to the AS slots. */
+ struct panthor_as_slot slots[MAX_AS_SLOTS];
+
+ /**
+ * @lru_list: List of least recently used VMs.
+ *
+ * We use this list to pick a VM to evict when all slots are
+ * used.
+ *
+ * There should be no more active VMs than there are AS slots,
+ * so this LRU is just here to keep VMs bound until there's
+ * a need to release a slot, thus avoid unnecessary TLB/cache
+ * flushes.
+ */
+ struct list_head lru_list;
+ } as;
+
+ /** @vm: VMs management fields */
+ struct {
+ /** @lock: Lock protecting access to list. */
+ struct mutex lock;
+
+ /** @list: List containing all VMs. */
+ struct list_head list;
+
+ /** @reset_in_progress: True if a reset is in progress. */
+ bool reset_in_progress;
+
+ /** @wq: Workqueue used for the VM_BIND queues. */
+ struct workqueue_struct *wq;
+ } vm;
+};
+
+/**
+ * struct panthor_vm_pool - VM pool object
+ */
+struct panthor_vm_pool {
+ /** @xa: Array used for VM handle tracking. */
+ struct xarray xa;
+};
+
+/**
+ * struct panthor_vma - GPU mapping object
+ *
+ * This is used to track GEM mappings in GPU space.
+ */
+struct panthor_vma {
+ /** @base: Inherits from drm_gpuva. */
+ struct drm_gpuva base;
+
+ /** @node: Used to implement deferred release of VMAs. */
+ struct list_head node;
+
+ /**
+ * @flags: Combination of drm_panthor_vm_bind_op_flags.
+ *
+ * Only map related flags are accepted.
+ */
+ u32 flags;
+};
+
+/**
+ * struct panthor_vm_op_ctx - VM operation context
+ *
+ * With VM operations potentially taking place in a dma-signaling path, we
+ * need to make sure everything that might require resource allocation is
+ * pre-allocated upfront. This is what this operation context is far.
+ *
+ * We also collect resources that have been freed, so we can release them
+ * asynchronously, and let the VM_BIND scheduler process the next VM_BIND
+ * request.
+ */
+struct panthor_vm_op_ctx {
+ /** @rsvd_page_tables: Pages reserved for the MMU page table update. */
+ struct {
+ /** @count: Number of pages reserved. */
+ u32 count;
+
+ /** @ptr: Point to the first unused page in the @pages table. */
+ u32 ptr;
+
+ /**
+ * @page: Array of pages that can be used for an MMU page table update.
+ *
+ * After an VM operation, there might be free pages left in this array.
+ * They should be returned to the pt_cache as part of the op_ctx cleanup.
+ */
+ void **pages;
+ } rsvd_page_tables;
+
+ /**
+ * @preallocated_vmas: Pre-allocated VMAs to handle the remap case.
+ *
+ * Partial unmap requests or map requests overlapping existing mappings will
+ * trigger a remap call, which need to register up to three panthor_vma objects
+ * (one for the new mapping, and two for the previous and next mappings).
+ */
+ struct panthor_vma *preallocated_vmas[3];
+
+ /** @flags: Combination of drm_panthor_vm_bind_op_flags. */
+ u32 flags;
+
+ /** @va: Virtual range targeted by the VM operation. */
+ struct {
+ /** @addr: Start address. */
+ u64 addr;
+
+ /** @range: Range size. */
+ u64 range;
+ } va;
+
+ /**
+ * @returned_vmas: List of panthor_vma objects returned after a VM operation.
+ *
+ * For unmap operations, this will contain all VMAs that were covered by the
+ * specified VA range.
+ *
+ * For map operations, this will contain all VMAs that previously mapped to
+ * the specified VA range.
+ *
+ * Those VMAs, and the resources they point to will be released as part of
+ * the op_ctx cleanup operation.
+ */
+ struct list_head returned_vmas;
+
+ /** @map: Fields specific to a map operation. */
+ struct {
+ /** @vm_bo: Buffer object to map. */
+ struct drm_gpuvm_bo *vm_bo;
+
+ /** @bo_offset: Offset in the buffer object. */
+ u64 bo_offset;
+
+ /**
+ * @sgt: sg-table pointing to pages backing the GEM object.
+ *
+ * This is gathered at job creation time, such that we don't have
+ * to allocate in ::run_job().
+ */
+ struct sg_table *sgt;
+
+ /**
+ * @new_vma: The new VMA object that will be inserted to the VA tree.
+ */
+ struct panthor_vma *new_vma;
+ } map;
+};
+
+/**
+ * struct panthor_vm - VM object
+ *
+ * A VM is an object representing a GPU (or MCU) virtual address space.
+ * It embeds the MMU page table for this address space, a tree containing
+ * all the virtual mappings of GEM objects, and other things needed to manage
+ * the VM.
+ *
+ * Except for the MCU VM, which is managed by the kernel, all other VMs are
+ * created by userspace and mostly managed by userspace, using the
+ * %DRM_IOCTL_PANTHOR_VM_BIND ioctl.
+ *
+ * A portion of the virtual address space is reserved for kernel objects,
+ * like heap chunks, and userspace gets to decide how much of the virtual
+ * address space is left to the kernel (half of the virtual address space
+ * by default).
+ */
+struct panthor_vm {
+ /**
+ * @base: Inherit from drm_gpuvm.
+ *
+ * We delegate all the VA management to the common drm_gpuvm framework
+ * and only implement hooks to update the MMU page table.
+ */
+ struct drm_gpuvm base;
+
+ /**
+ * @sched: Scheduler used for asynchronous VM_BIND request.
+ *
+ * We use a 1:1 scheduler here.
+ */
+ struct drm_gpu_scheduler sched;
+
+ /**
+ * @entity: Scheduling entity representing the VM_BIND queue.
+ *
+ * There's currently one bind queue per VM. It doesn't make sense to
+ * allow more given the VM operations are serialized anyway.
+ */
+ struct drm_sched_entity entity;
+
+ /** @ptdev: Device. */
+ struct panthor_device *ptdev;
+
+ /** @memattr: Value to program to the AS_MEMATTR register. */
+ u64 memattr;
+
+ /** @pgtbl_ops: Page table operations. */
+ struct io_pgtable_ops *pgtbl_ops;
+
+ /** @root_page_table: Stores the root page table pointer. */
+ void *root_page_table;
+
+ /**
+ * @op_lock: Lock used to serialize operations on a VM.
+ *
+ * The serialization of jobs queued to the VM_BIND queue is already
+ * taken care of by drm_sched, but we need to serialize synchronous
+ * and asynchronous VM_BIND request. This is what this lock is for.
+ */
+ struct mutex op_lock;
+
+ /**
+ * @op_ctx: The context attached to the currently executing VM operation.
+ *
+ * NULL when no operation is in progress.
+ */
+ struct panthor_vm_op_ctx *op_ctx;
+
+ /**
+ * @mm: Memory management object representing the auto-VA/kernel-VA.
+ *
+ * Used to auto-allocate VA space for kernel-managed objects (tiler
+ * heaps, ...).
+ *
+ * For the MCU VM, this is managing the VA range that's used to map
+ * all shared interfaces.
+ *
+ * For user VMs, the range is specified by userspace, and must not
+ * exceed half of the VA space addressable.
+ */
+ struct drm_mm mm;
+
+ /** @mm_lock: Lock protecting the @mm field. */
+ struct mutex mm_lock;
+
+ /** @kernel_auto_va: Automatic VA-range for kernel BOs. */
+ struct {
+ /** @start: Start of the automatic VA-range for kernel BOs. */
+ u64 start;
+
+ /** @size: Size of the automatic VA-range for kernel BOs. */
+ u64 end;
+ } kernel_auto_va;
+
+ /** @as: Address space related fields. */
+ struct {
+ /**
+ * @id: ID of the address space this VM is bound to.
+ *
+ * A value of -1 means the VM is inactive/not bound.
+ */
+ int id;
+
+ /** @active_cnt: Number of active users of this VM. */
+ refcount_t active_cnt;
+
+ /**
+ * @lru_node: Used to instead the VM in the panthor_mmu::as::lru_list.
+ *
+ * Active VMs should not be inserted in the LRU list.
+ */
+ struct list_head lru_node;
+ } as;
+
+ /**
+ * @heaps: Tiler heap related fields.
+ */
+ struct {
+ /**
+ * @pool: The heap pool attached to this VM.
+ *
+ * Will stay NULL until someone creates a heap context on this VM.
+ */
+ struct panthor_heap_pool *pool;
+
+ /** @lock: Lock used to protect access to @pool. */
+ struct mutex lock;
+ } heaps;
+
+ /** @node: Used to insert the VM in the panthor_mmu::vm::list. */
+ struct list_head node;
+
+ /** @for_mcu: True if this is the MCU VM. */
+ bool for_mcu;
+
+ /**
+ * @destroyed: True if the VM was destroyed.
+ *
+ * No further bind requests should be queued to a destroyed VM.
+ */
+ bool destroyed;
+
+ /**
+ * @unusable: True if the VM has turned unusable because something
+ * bad happened during an asynchronous request.
+ *
+ * We don't try to recover from such failures, because this implies
+ * informing userspace about the specific operation that failed, and
+ * hoping the userspace driver can replay things from there. This all
+ * sounds very complicated for little gain.
+ *
+ * Instead, we should just flag the VM as unusable, and fail any
+ * further request targeting this VM.
+ *
+ * We also provide a way to query a VM state, so userspace can destroy
+ * it and create a new one.
+ *
+ * As an analogy, this would be mapped to a VK_ERROR_DEVICE_LOST
+ * situation, where the logical device needs to be re-created.
+ */
+ bool unusable;
+
+ /**
+ * @unhandled_fault: Unhandled fault happened.
+ *
+ * This should be reported to the scheduler, and the queue/group be
+ * flagged as faulty as a result.
+ */
+ bool unhandled_fault;
+};
+
+/**
+ * struct panthor_vm_bind_job - VM bind job
+ */
+struct panthor_vm_bind_job {
+ /** @base: Inherit from drm_sched_job. */
+ struct drm_sched_job base;
+
+ /** @refcount: Reference count. */
+ struct kref refcount;
+
+ /** @cleanup_op_ctx_work: Work used to cleanup the VM operation context. */
+ struct work_struct cleanup_op_ctx_work;
+
+ /** @vm: VM targeted by the VM operation. */
+ struct panthor_vm *vm;
+
+ /** @ctx: Operation context. */
+ struct panthor_vm_op_ctx ctx;
+};
+
+/**
+ * @pt_cache: Cache used to allocate MMU page tables.
+ *
+ * The pre-allocation pattern forces us to over-allocate to plan for
+ * the worst case scenario, and return the pages we didn't use.
+ *
+ * Having a kmem_cache allows us to speed allocations.
+ */
+static struct kmem_cache *pt_cache;
+
+/**
+ * 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 *alloc_pt(void *cookie, size_t size, gfp_t gfp)
+{
+ struct panthor_vm *vm = cookie;
+ void *page;
+
+ /* Allocation of the root page table happening during init. */
+ if (unlikely(!vm->root_page_table)) {
+ struct page *p;
+
+ drm_WARN_ON(&vm->ptdev->base, vm->op_ctx);
+ p = alloc_pages_node(dev_to_node(vm->ptdev->base.dev),
+ gfp | __GFP_ZERO, get_order(size));
+ page = p ? page_address(p) : NULL;
+ vm->root_page_table = page;
+ return page;
+ }
+
+ /* We're not supposed to have anything bigger than 4k here, because we picked a
+ * 4k granule size at init time.
+ */
+ if (drm_WARN_ON(&vm->ptdev->base, size != SZ_4K))
+ return NULL;
+
+ /* We must have some op_ctx attached to the VM and it must have at least one
+ * free page.
+ */
+ if (drm_WARN_ON(&vm->ptdev->base, !vm->op_ctx) ||
+ drm_WARN_ON(&vm->ptdev->base,
+ vm->op_ctx->rsvd_page_tables.ptr >= vm->op_ctx->rsvd_page_tables.count))
+ return NULL;
+
+ page = vm->op_ctx->rsvd_page_tables.pages[vm->op_ctx->rsvd_page_tables.ptr++];
+ memset(page, 0, SZ_4K);
+
+ /* 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 free_pt(void *cookie, void *data, size_t size)
+{
+ struct panthor_vm *vm = cookie;
+
+ if (unlikely(vm->root_page_table == data)) {
+ free_pages((unsigned long)data, get_order(size));
+ vm->root_page_table = NULL;
+ return;
+ }
+
+ if (drm_WARN_ON(&vm->ptdev->base, size != SZ_4K))
+ return;
+
+ /* Return the page to the pt_cache. */
+ kmem_cache_free(pt_cache, data);
+}
+
+static int wait_ready(struct panthor_device *ptdev, u32 as_nr)
+{
+ int ret;
+ u32 val;
+
+ /* Wait for the MMU status to indicate there is no active command, in
+ * case one is pending.
+ */
+ ret = readl_relaxed_poll_timeout_atomic(ptdev->iomem + AS_STATUS(as_nr),
+ val, !(val & AS_STATUS_AS_ACTIVE),
+ 10, 100000);
+
+ if (ret) {
+ panthor_device_schedule_reset(ptdev);
+ drm_err(&ptdev->base, "AS_ACTIVE bit stuck\n");
+ }
+
+ return ret;
+}
+
+static int write_cmd(struct panthor_device *ptdev, u32 as_nr, u32 cmd)
+{
+ int status;
+
+ /* write AS_COMMAND when MMU is ready to accept another command */
+ status = wait_ready(ptdev, as_nr);
+ if (!status)
+ gpu_write(ptdev, AS_COMMAND(as_nr), cmd);
+
+ return status;
+}
+
+static void lock_region(struct panthor_device *ptdev, u32 as_nr,
+ u64 region_start, u64 size)
+{
+ u8 region_width;
+ u64 region;
+ u64 region_end = region_start + size;
+
+ if (!size)
+ return;
+
+ /*
+ * The locked region is a naturally aligned power of 2 block encoded as
+ * log2 minus(1).
+ * Calculate the desired start/end and look for the highest bit which
+ * differs. The smallest naturally aligned block must include this bit
+ * change, the desired region starts with this bit (and subsequent bits)
+ * zeroed and ends with the bit (and subsequent bits) set to one.
+ */
+ region_width = max(fls64(region_start ^ (region_end - 1)),
+ const_ilog2(AS_LOCK_REGION_MIN_SIZE)) - 1;
+
+ /*
+ * Mask off the low bits of region_start (which would be ignored by
+ * the hardware anyway)
+ */
+ region_start &= GENMASK_ULL(63, region_width);
+
+ region = region_width | region_start;
+
+ /* Lock the region that needs to be updated */
+ gpu_write(ptdev, AS_LOCKADDR_LO(as_nr), lower_32_bits(region));
+ gpu_write(ptdev, AS_LOCKADDR_HI(as_nr), upper_32_bits(region));
+ write_cmd(ptdev, as_nr, AS_COMMAND_LOCK);
+}
+
+static int mmu_hw_do_operation_locked(struct panthor_device *ptdev, int as_nr,
+ u64 iova, u64 size, u32 op)
+{
+ lockdep_assert_held(&ptdev->mmu->as.slots_lock);
+
+ if (as_nr < 0)
+ return 0;
+
+ if (op != AS_COMMAND_UNLOCK)
+ lock_region(ptdev, as_nr, iova, size);
+
+ /* Run the MMU operation */
+ write_cmd(ptdev, as_nr, op);
+
+ /* Wait for the flush to complete */
+ return wait_ready(ptdev, as_nr);
+}
+
+static int mmu_hw_do_operation(struct panthor_vm *vm,
+ u64 iova, u64 size, u32 op)
+{
+ struct panthor_device *ptdev = vm->ptdev;
+ int ret;
+
+ mutex_lock(&ptdev->mmu->as.slots_lock);
+ ret = mmu_hw_do_operation_locked(ptdev, vm->as.id, iova, size, op);
+ mutex_unlock(&ptdev->mmu->as.slots_lock);
+
+ return ret;
+}
+
+static int panthor_mmu_as_enable(struct panthor_device *ptdev, u32 as_nr,
+ u64 transtab, u64 transcfg, u64 memattr)
+{
+ int ret;
+
+ ret = mmu_hw_do_operation_locked(ptdev, as_nr, 0, ~0ULL, AS_COMMAND_FLUSH_MEM);
+ if (ret)
+ return ret;
+
+ gpu_write(ptdev, AS_TRANSTAB_LO(as_nr), lower_32_bits(transtab));
+ gpu_write(ptdev, AS_TRANSTAB_HI(as_nr), upper_32_bits(transtab));
+
+ gpu_write(ptdev, AS_MEMATTR_LO(as_nr), lower_32_bits(memattr));
+ gpu_write(ptdev, AS_MEMATTR_HI(as_nr), upper_32_bits(memattr));
+
+ gpu_write(ptdev, AS_TRANSCFG_LO(as_nr), lower_32_bits(transcfg));
+ gpu_write(ptdev, AS_TRANSCFG_HI(as_nr), upper_32_bits(transcfg));
+
+ return write_cmd(ptdev, as_nr, AS_COMMAND_UPDATE);
+}
+
+static int panthor_mmu_as_disable(struct panthor_device *ptdev, u32 as_nr)
+{
+ int ret;
+
+ ret = mmu_hw_do_operation_locked(ptdev, as_nr, 0, ~0ULL, AS_COMMAND_FLUSH_MEM);
+ if (ret)
+ return ret;
+
+ gpu_write(ptdev, AS_TRANSTAB_LO(as_nr), 0);
+ gpu_write(ptdev, AS_TRANSTAB_HI(as_nr), 0);
+
+ gpu_write(ptdev, AS_MEMATTR_LO(as_nr), 0);
+ gpu_write(ptdev, AS_MEMATTR_HI(as_nr), 0);
+
+ gpu_write(ptdev, AS_TRANSCFG_LO(as_nr), AS_TRANSCFG_ADRMODE_UNMAPPED);
+ gpu_write(ptdev, AS_TRANSCFG_HI(as_nr), 0);
+
+ return write_cmd(ptdev, as_nr, AS_COMMAND_UPDATE);
+}
+
+static u32 panthor_mmu_fault_mask(struct panthor_device *ptdev, u32 value)
+{
+ /* Bits 16 to 31 mean REQ_COMPLETE. */
+ return value & GENMASK(15, 0);
+}
+
+static u32 panthor_mmu_as_fault_mask(struct panthor_device *ptdev, u32 as)
+{
+ return BIT(as);
+}
+
+/**
+ * panthor_vm_has_unhandled_faults() - Check if a VM has unhandled faults
+ * @vm: VM to check.
+ *
+ * Return: true if the VM has unhandled faults, false otherwise.
+ */
+bool panthor_vm_has_unhandled_faults(struct panthor_vm *vm)
+{
+ return vm->unhandled_fault;
+}
+
+/**
+ * panthor_vm_is_unusable() - Check if the VM is still usable
+ * @vm: VM to check.
+ *
+ * Return: true if the VM is unusable, false otherwise.
+ */
+bool panthor_vm_is_unusable(struct panthor_vm *vm)
+{
+ return vm->unusable;
+}
+
+static void panthor_vm_release_as_locked(struct panthor_vm *vm)
+{
+ struct panthor_device *ptdev = vm->ptdev;
+
+ lockdep_assert_held(&ptdev->mmu->as.slots_lock);
+
+ if (drm_WARN_ON(&ptdev->base, vm->as.id < 0))
+ return;
+
+ ptdev->mmu->as.slots[vm->as.id].vm = NULL;
+ clear_bit(vm->as.id, &ptdev->mmu->as.alloc_mask);
+ refcount_set(&vm->as.active_cnt, 0);
+ list_del_init(&vm->as.lru_node);
+ vm->as.id = -1;
+}
+
+/**
+ * panthor_vm_active() - Flag a VM as active
+ * @VM: VM to flag as active.
+ *
+ * Assigns an address space to a VM so it can be used by the GPU/MCU.
+ *
+ * Return: 0 on success, a negative error code otherwise.
+ */
+int panthor_vm_active(struct panthor_vm *vm)
+{
+ struct panthor_device *ptdev = vm->ptdev;
+ u32 va_bits = GPU_MMU_FEATURES_VA_BITS(ptdev->gpu_info.mmu_features);
+ struct io_pgtable_cfg *cfg = &io_pgtable_ops_to_pgtable(vm->pgtbl_ops)->cfg;
+ int ret = 0, as, cookie;
+ u64 transtab, transcfg;
+
+ if (!drm_dev_enter(&ptdev->base, &cookie))
+ return -ENODEV;
+
+ if (refcount_inc_not_zero(&vm->as.active_cnt))
+ goto out_dev_exit;
+
+ mutex_lock(&ptdev->mmu->as.slots_lock);
+
+ if (refcount_inc_not_zero(&vm->as.active_cnt))
+ goto out_unlock;
+
+ as = vm->as.id;
+ if (as >= 0) {
+ /* Unhandled pagefault on this AS, the MMU was disabled. We need to
+ * re-enable the MMU after clearing+unmasking the AS interrupts.
+ */
+ if (ptdev->mmu->as.faulty_mask & panthor_mmu_as_fault_mask(ptdev, as))
+ goto out_enable_as;
+
+ goto out_make_active;
+ }
+
+ /* Check for a free AS */
+ if (vm->for_mcu) {
+ drm_WARN_ON(&ptdev->base, ptdev->mmu->as.alloc_mask & BIT(0));
+ as = 0;
+ } else {
+ as = ffz(ptdev->mmu->as.alloc_mask | BIT(0));
+ }
+
+ if (!(BIT(as) & ptdev->gpu_info.as_present)) {
+ struct panthor_vm *lru_vm;
+
+ lru_vm = list_first_entry_or_null(&ptdev->mmu->as.lru_list,
+ struct panthor_vm,
+ as.lru_node);
+ if (drm_WARN_ON(&ptdev->base, !lru_vm)) {
+ ret = -EBUSY;
+ goto out_unlock;
+ }
+
+ drm_WARN_ON(&ptdev->base, refcount_read(&lru_vm->as.active_cnt));
+ as = lru_vm->as.id;
+ panthor_vm_release_as_locked(lru_vm);
+ }
+
+ /* Assign the free or reclaimed AS to the FD */
+ vm->as.id = as;
+ set_bit(as, &ptdev->mmu->as.alloc_mask);
+ ptdev->mmu->as.slots[as].vm = vm;
+
+out_enable_as:
+ transtab = cfg->arm_lpae_s1_cfg.ttbr;
+ transcfg = AS_TRANSCFG_PTW_MEMATTR_WB |
+ AS_TRANSCFG_PTW_RA |
+ AS_TRANSCFG_ADRMODE_AARCH64_4K |
+ AS_TRANSCFG_INA_BITS(55 - va_bits);
+ if (ptdev->coherent)
+ transcfg |= AS_TRANSCFG_PTW_SH_OS;
+
+ /* If the VM is re-activated, we clear the fault. */
+ vm->unhandled_fault = false;
+
+ /* Unhandled pagefault on this AS, clear the fault and re-enable interrupts
+ * before enabling the AS.
+ */
+ if (ptdev->mmu->as.faulty_mask & panthor_mmu_as_fault_mask(ptdev, as)) {
+ gpu_write(ptdev, MMU_INT_CLEAR, panthor_mmu_as_fault_mask(ptdev, as));
+ ptdev->mmu->as.faulty_mask &= ~panthor_mmu_as_fault_mask(ptdev, as);
+ gpu_write(ptdev, MMU_INT_MASK, ~ptdev->mmu->as.faulty_mask);
+ }
+
+ ret = panthor_mmu_as_enable(vm->ptdev, vm->as.id, transtab, transcfg, vm->memattr);
+
+out_make_active:
+ if (!ret) {
+ refcount_set(&vm->as.active_cnt, 1);
+ list_del_init(&vm->as.lru_node);
+ }
+
+out_unlock:
+ mutex_unlock(&ptdev->mmu->as.slots_lock);
+
+out_dev_exit:
+ drm_dev_exit(cookie);
+ return ret;
+}
+
+/**
+ * panthor_vm_idle() - Flag a VM idle
+ * @VM: VM to flag as idle.
+ *
+ * When we know the GPU is done with the VM (no more jobs to process),
+ * we can relinquish the AS slot attached to this VM, if any.
+ *
+ * We don't release the slot immediately, but instead place the VM in
+ * the LRU list, so it can be evicted if another VM needs an AS slot.
+ * This way, VMs keep attached to the AS they were given until we run
+ * out of free slot, limiting the number of MMU operations (TLB flush
+ * and other AS updates).
+ */
+void panthor_vm_idle(struct panthor_vm *vm)
+{
+ struct panthor_device *ptdev = vm->ptdev;
+
+ if (!refcount_dec_and_mutex_lock(&vm->as.active_cnt, &ptdev->mmu->as.slots_lock))
+ return;
+
+ if (!drm_WARN_ON(&ptdev->base, vm->as.id == -1 || !list_empty(&vm->as.lru_node)))
+ list_add_tail(&vm->as.lru_node, &ptdev->mmu->as.lru_list);
+
+ refcount_set(&vm->as.active_cnt, 0);
+ mutex_unlock(&ptdev->mmu->as.slots_lock);
+}
+
+static void panthor_vm_stop(struct panthor_vm *vm)
+{
+ drm_sched_stop(&vm->sched, NULL);
+}
+
+static void panthor_vm_start(struct panthor_vm *vm)
+{
+ drm_sched_start(&vm->sched, true);
+}
+
+/**
+ * panthor_vm_as() - Get the AS slot attached to a VM
+ * @vm: VM to get the AS slot of.
+ *
+ * Return: -1 if the VM is not assigned an AS slot yet, >= 0 otherwise.
+ */
+int panthor_vm_as(struct panthor_vm *vm)
+{
+ return vm->as.id;
+}
+
+static size_t get_pgsize(u64 addr, size_t size, size_t *count)
+{
+ /*
+ * io-pgtable only operates on multiple pages within a single table
+ * entry, so we need to split at boundaries of the table size, i.e.
+ * the next block size up. The distance from address A to the next
+ * boundary of block size B is logically B - A % B, but in unsigned
+ * two's complement where B is a power of two we get the equivalence
+ * B - A % B == (B - A) % B == (n * B - A) % B, and choose n = 0 :)
+ */
+ size_t blk_offset = -addr % SZ_2M;
+
+ if (blk_offset || size < SZ_2M) {
+ *count = min_not_zero(blk_offset, size) / SZ_4K;
+ return SZ_4K;
+ }
+ blk_offset = -addr % SZ_1G ?: SZ_1G;
+ *count = min(blk_offset, size) / SZ_2M;
+ return SZ_2M;
+}
+
+static int panthor_vm_flush_range(struct panthor_vm *vm, u64 iova, u64 size)
+{
+ struct panthor_device *ptdev = vm->ptdev;
+ int ret = 0, cookie;
+
+ if (vm->as.id < 0)
+ return 0;
+
+ /* If the device is unplugged, we just silently skip the flush. */
+ if (!drm_dev_enter(&ptdev->base, &cookie))
+ return 0;
+
+ /* Flush the PTs only if we're already awake */
+ if (pm_runtime_active(ptdev->base.dev))
+ ret = mmu_hw_do_operation(vm, iova, size, AS_COMMAND_FLUSH_PT);
+
+ drm_dev_exit(cookie);
+ return ret;
+}
+
+static int panthor_vm_unmap_pages(struct panthor_vm *vm, u64 iova, u64 size)
+{
+ struct panthor_device *ptdev = vm->ptdev;
+ struct io_pgtable_ops *ops = vm->pgtbl_ops;
+ u64 offset = 0;
+
+ drm_dbg(&ptdev->base, "unmap: as=%d, iova=%llx, len=%llx", vm->as.id, iova, size);
+
+ while (offset < size) {
+ size_t unmapped_sz = 0, pgcount;
+ size_t pgsize = get_pgsize(iova + offset, size - offset, &pgcount);
+
+ unmapped_sz = ops->unmap_pages(ops, iova + offset, pgsize, pgcount, NULL);
+
+ if (drm_WARN_ON(&ptdev->base, unmapped_sz != pgsize * pgcount)) {
+ drm_err(&ptdev->base, "failed to unmap range %llx-%llx (requested range %llx-%llx)\n",
+ iova + offset + unmapped_sz,
+ iova + offset + pgsize * pgcount,
+ iova, iova + size);
+ panthor_vm_flush_range(vm, iova, offset + unmapped_sz);
+ return -EINVAL;
+ }
+ offset += unmapped_sz;
+ }
+
+ return panthor_vm_flush_range(vm, iova, size);
+}
+
+static int
+panthor_vm_map_pages(struct panthor_vm *vm, u64 iova, int prot,
+ struct sg_table *sgt, u64 offset, u64 size)
+{
+ struct panthor_device *ptdev = vm->ptdev;
+ unsigned int count;
+ struct scatterlist *sgl;
+ struct io_pgtable_ops *ops = vm->pgtbl_ops;
+ u64 start_iova = iova;
+ int ret;
+
+ if (!size)
+ return 0;
+
+ for_each_sgtable_dma_sg(sgt, sgl, count) {
+ dma_addr_t paddr = sg_dma_address(sgl);
+ size_t len = sg_dma_len(sgl);
+
+ if (len <= offset) {
+ offset -= len;
+ continue;
+ }
+
+ paddr += offset;
+ len -= offset;
+ len = min_t(size_t, len, size);
+ size -= len;
+
+ drm_dbg(&ptdev->base, "map: as=%d, iova=%llx, paddr=%pad, len=%zx",
+ vm->as.id, iova, &paddr, len);
+
+ while (len) {
+ size_t pgcount, mapped = 0;
+ size_t pgsize = get_pgsize(iova | paddr, len, &pgcount);
+
+ ret = ops->map_pages(ops, iova, paddr, pgsize, pgcount, prot,
+ GFP_KERNEL, &mapped);
+ iova += mapped;
+ paddr += mapped;
+ len -= mapped;
+
+ if (drm_WARN_ON(&ptdev->base, !ret && !mapped))
+ ret = -ENOMEM;
+
+ if (ret) {
+ /* If something failed, unmap what we've already mapped before
+ * returning. The unmap call is not supposed to fail.
+ */
+ drm_WARN_ON(&ptdev->base,
+ panthor_vm_unmap_pages(vm, start_iova,
+ iova - start_iova));
+ return ret;
+ }
+ }
+
+ if (!size)
+ break;
+ }
+
+ return panthor_vm_flush_range(vm, start_iova, iova - start_iova);
+}
+
+static int flags_to_prot(u32 flags)
+{
+ int prot = 0;
+
+ if (flags & DRM_PANTHOR_VM_BIND_OP_MAP_NOEXEC)
+ prot |= IOMMU_NOEXEC;
+
+ if (!(flags & DRM_PANTHOR_VM_BIND_OP_MAP_UNCACHED))
+ prot |= IOMMU_CACHE;
+
+ if (flags & DRM_PANTHOR_VM_BIND_OP_MAP_READONLY)
+ prot |= IOMMU_READ;
+ else
+ prot |= IOMMU_READ | IOMMU_WRITE;
+
+ return prot;
+}
+
+/**
+ * panthor_vm_alloc_va() - Allocate a region in the auto-va space
+ * @VM: VM to allocate a region on.
+ * @va: start of the VA range. Can be PANTHOR_VM_KERNEL_AUTO_VA if the user
+ * wants the VA to be automatically allocated from the auto-VA range.
+ * @size: size of the VA range.
+ * @va_node: drm_mm_node to initialize. Must be zero-initialized.
+ *
+ * Some GPU objects, like heap chunks, are fully managed by the kernel and
+ * need to be mapped to the userspace VM, in the region reserved for kernel
+ * objects.
+ *
+ * This function takes care of allocating a region in the kernel auto-VA space.
+ *
+ * Return: 0 on success, an error code otherwise.
+ */
+int
+panthor_vm_alloc_va(struct panthor_vm *vm, u64 va, u64 size,
+ struct drm_mm_node *va_node)
+{
+ int ret;
+
+ if (!size || (size & ~PAGE_MASK))
+ return -EINVAL;
+
+ if (va != PANTHOR_VM_KERNEL_AUTO_VA && (va & ~PAGE_MASK))
+ return -EINVAL;
+
+ mutex_lock(&vm->mm_lock);
+ if (va != PANTHOR_VM_KERNEL_AUTO_VA) {
+ va_node->start = va;
+ va_node->size = size;
+ ret = drm_mm_reserve_node(&vm->mm, va_node);
+ } else {
+ ret = drm_mm_insert_node_in_range(&vm->mm, va_node, size,
+ size >= SZ_2M ? SZ_2M : SZ_4K,
+ 0, vm->kernel_auto_va.start,
+ vm->kernel_auto_va.end,
+ DRM_MM_INSERT_BEST);
+ }
+ mutex_unlock(&vm->mm_lock);
+
+ return ret;
+}
+
+/**
+ * panthor_vm_free_va() - Free a region allocated with panthor_vm_alloc_va()
+ * @VM: VM to free the region on.
+ * @va_node: Memory node representing the region to free.
+ */
+void panthor_vm_free_va(struct panthor_vm *vm, struct drm_mm_node *va_node)
+{
+ mutex_lock(&vm->mm_lock);
+ drm_mm_remove_node(va_node);
+ mutex_unlock(&vm->mm_lock);
+}
+
+static void panthor_vm_bo_put(struct drm_gpuvm_bo *vm_bo)
+{
+ struct panthor_gem_object *bo = to_panthor_bo(vm_bo->obj);
+ struct drm_gpuvm *vm = vm_bo->vm;
+ bool unpin;
+
+ /* We must retain the GEM before calling drm_gpuvm_bo_put(),
+ * otherwise the mutex might be destroyed while we hold it.
+ * Same goes for the VM, since we take the VM resv lock.
+ */
+ drm_gem_object_get(&bo->base.base);
+ drm_gpuvm_get(vm);
+
+ /* We take the resv lock to protect against concurrent accesses to the
+ * gpuvm evicted/extobj lists that are modified in
+ * drm_gpuvm_bo_destroy(), which is called if drm_gpuvm_bo_put()
+ * releases sthe last vm_bo reference.
+ * We take the BO GPUVA list lock to protect the vm_bo removal from the
+ * GEM vm_bo list.
+ */
+ dma_resv_lock(drm_gpuvm_resv(vm), NULL);
+ mutex_lock(&bo->gpuva_list_lock);
+ unpin = drm_gpuvm_bo_put(vm_bo);
+ mutex_unlock(&bo->gpuva_list_lock);
+ dma_resv_unlock(drm_gpuvm_resv(vm));
+
+ /* If the vm_bo object was destroyed, release the pin reference that
+ * was hold by this object.
+ */
+ if (unpin && !bo->base.base.import_attach)
+ drm_gem_shmem_unpin(&bo->base);
+
+ drm_gpuvm_put(vm);
+ drm_gem_object_put(&bo->base.base);
+}
+
+static void panthor_vm_cleanup_op_ctx(struct panthor_vm_op_ctx *op_ctx,
+ struct panthor_vm *vm)
+{
+ struct panthor_vma *vma, *tmp_vma;
+
+ u32 remaining_pt_count = op_ctx->rsvd_page_tables.count -
+ op_ctx->rsvd_page_tables.ptr;
+
+ if (remaining_pt_count) {
+ kmem_cache_free_bulk(pt_cache, remaining_pt_count,
+ op_ctx->rsvd_page_tables.pages +
+ op_ctx->rsvd_page_tables.ptr);
+ }
+
+ kfree(op_ctx->rsvd_page_tables.pages);
+
+ if (op_ctx->map.vm_bo)
+ panthor_vm_bo_put(op_ctx->map.vm_bo);
+
+ for (u32 i = 0; i < ARRAY_SIZE(op_ctx->preallocated_vmas); i++)
+ kfree(op_ctx->preallocated_vmas[i]);
+
+ list_for_each_entry_safe(vma, tmp_vma, &op_ctx->returned_vmas, node) {
+ list_del(&vma->node);
+ panthor_vm_bo_put(vma->base.vm_bo);
+ kfree(vma);
+ }
+}
+
+static struct panthor_vma *
+panthor_vm_op_ctx_get_vma(struct panthor_vm_op_ctx *op_ctx)
+{
+ for (u32 i = 0; i < ARRAY_SIZE(op_ctx->preallocated_vmas); i++) {
+ struct panthor_vma *vma = op_ctx->preallocated_vmas[i];
+
+ if (vma) {
+ op_ctx->preallocated_vmas[i] = NULL;
+ return vma;
+ }
+ }
+
+ return NULL;
+}
+
+static int
+panthor_vm_op_ctx_prealloc_vmas(struct panthor_vm_op_ctx *op_ctx)
+{
+ u32 vma_count;
+
+ switch (op_ctx->flags & DRM_PANTHOR_VM_BIND_OP_TYPE_MASK) {
+ case DRM_PANTHOR_VM_BIND_OP_TYPE_MAP:
+ /* One VMA for the new mapping, and two more VMAs for the remap case
+ * which might contain both a prev and next VA.
+ */
+ vma_count = 3;
+ break;
+
+ case DRM_PANTHOR_VM_BIND_OP_TYPE_UNMAP:
+ /* Partial unmaps might trigger a remap with either a prev or a next VA,
+ * but not both.
+ */
+ vma_count = 1;
+ break;
+
+ default:
+ return 0;
+ }
+
+ for (u32 i = 0; i < vma_count; i++) {
+ struct panthor_vma *vma = kzalloc(sizeof(*vma), GFP_KERNEL);
+
+ if (!vma)
+ return -ENOMEM;
+
+ op_ctx->preallocated_vmas[i] = vma;
+ }
+
+ return 0;
+}
+
+#define PANTHOR_VM_BIND_OP_MAP_FLAGS \
+ (DRM_PANTHOR_VM_BIND_OP_MAP_READONLY | \
+ DRM_PANTHOR_VM_BIND_OP_MAP_NOEXEC | \
+ DRM_PANTHOR_VM_BIND_OP_MAP_UNCACHED | \
+ DRM_PANTHOR_VM_BIND_OP_TYPE_MASK)
+
+static int panthor_vm_prepare_map_op_ctx(struct panthor_vm_op_ctx *op_ctx,
+ struct panthor_vm *vm,
+ struct panthor_gem_object *bo,
+ u64 offset,
+ u64 size, u64 va,
+ u32 flags)
+{
+ struct drm_gpuvm_bo *preallocated_vm_bo;
+ struct sg_table *sgt = NULL;
+ u64 pt_count;
+ int ret;
+
+ if (!bo)
+ return -EINVAL;
+
+ if ((flags & ~PANTHOR_VM_BIND_OP_MAP_FLAGS) ||
+ (flags & DRM_PANTHOR_VM_BIND_OP_TYPE_MASK) != DRM_PANTHOR_VM_BIND_OP_TYPE_MAP)
+ return -EINVAL;
+
+ /* Make sure the VA and size are aligned and in-bounds. */
+ if (size > bo->base.base.size || offset > bo->base.base.size - size)
+ return -EINVAL;
+
+ /* If the BO has an exclusive VM attached, it can't be mapped to other VMs. */
+ if (bo->exclusive_vm_root_gem &&
+ bo->exclusive_vm_root_gem != panthor_vm_root_gem(vm))
+ return -EINVAL;
+
+ memset(op_ctx, 0, sizeof(*op_ctx));
+ INIT_LIST_HEAD(&op_ctx->returned_vmas);
+ op_ctx->flags = flags;
+ op_ctx->va.range = size;
+ op_ctx->va.addr = va;
+
+ ret = panthor_vm_op_ctx_prealloc_vmas(op_ctx);
+ if (ret)
+ goto err_cleanup;
+
+ if (!bo->base.base.import_attach) {
+ /* Pre-reserve the BO pages, so the map operation doesn't have to
+ * allocate.
+ */
+ ret = drm_gem_shmem_pin(&bo->base);
+ if (ret)
+ goto err_cleanup;
+ }
+
+ sgt = drm_gem_shmem_get_pages_sgt(&bo->base);
+ if (IS_ERR(sgt)) {
+ if (!bo->base.base.import_attach)
+ drm_gem_shmem_unpin(&bo->base);
+
+ ret = PTR_ERR(sgt);
+ goto err_cleanup;
+ }
+
+ op_ctx->map.sgt = sgt;
+
+ preallocated_vm_bo = drm_gpuvm_bo_create(&vm->base, &bo->base.base);
+ if (!preallocated_vm_bo) {
+ if (!bo->base.base.import_attach)
+ drm_gem_shmem_unpin(&bo->base);
+
+ ret = -ENOMEM;
+ goto err_cleanup;
+ }
+
+ mutex_lock(&bo->gpuva_list_lock);
+ op_ctx->map.vm_bo = drm_gpuvm_bo_obtain_prealloc(preallocated_vm_bo);
+ mutex_unlock(&bo->gpuva_list_lock);
+
+ /* If the a vm_bo for this <VM,BO> combination exists, it already
+ * retains a pin ref, and we can release the one we took earlier.
+ *
+ * If our pre-allocated vm_bo is picked, it now retains the pin ref,
+ * which will be released in panthor_vm_bo_put().
+ */
+ if (preallocated_vm_bo != op_ctx->map.vm_bo &&
+ !bo->base.base.import_attach)
+ drm_gem_shmem_unpin(&bo->base);
+
+ op_ctx->map.bo_offset = offset;
+
+ /* 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.
+ */
+ pt_count = ((ALIGN(va + size, 1ull << 39) - ALIGN_DOWN(va, 1ull << 39)) >> 39) +
+ ((ALIGN(va + size, 1ull << 30) - ALIGN_DOWN(va, 1ull << 30)) >> 30) +
+ ((ALIGN(va + size, 1ull << 21) - ALIGN_DOWN(va, 1ull << 21)) >> 21);
+
+ op_ctx->rsvd_page_tables.pages = kcalloc(pt_count,
+ sizeof(*op_ctx->rsvd_page_tables.pages),
+ GFP_KERNEL);
+ if (!op_ctx->rsvd_page_tables.pages)
+ goto err_cleanup;
+
+ ret = kmem_cache_alloc_bulk(pt_cache, GFP_KERNEL, pt_count,
+ op_ctx->rsvd_page_tables.pages);
+ op_ctx->rsvd_page_tables.count = ret;
+ if (ret != pt_count) {
+ ret = -ENOMEM;
+ goto err_cleanup;
+ }
+
+ /* Insert BO into the extobj list last, when we know nothing can fail. */
+ dma_resv_lock(panthor_vm_resv(vm), NULL);
+ drm_gpuvm_bo_extobj_add(op_ctx->map.vm_bo);
+ dma_resv_unlock(panthor_vm_resv(vm));
+
+ return 0;
+
+err_cleanup:
+ panthor_vm_cleanup_op_ctx(op_ctx, vm);
+ return ret;
+}
+
+static int panthor_vm_prepare_unmap_op_ctx(struct panthor_vm_op_ctx *op_ctx,
+ struct panthor_vm *vm,
+ u64 va, u64 size)
+{
+ u32 pt_count = 0;
+ int ret;
+
+ memset(op_ctx, 0, sizeof(*op_ctx));
+ INIT_LIST_HEAD(&op_ctx->returned_vmas);
+ op_ctx->va.range = size;
+ op_ctx->va.addr = va;
+ op_ctx->flags = DRM_PANTHOR_VM_BIND_OP_TYPE_UNMAP;
+
+ /* Pre-allocate L3 page tables to account for the split-2M-block
+ * situation on unmap.
+ */
+ if (va != ALIGN(va, SZ_2M))
+ pt_count++;
+
+ if (va + size != ALIGN(va + size, SZ_2M) &&
+ ALIGN(va + size, SZ_2M) != ALIGN(va, SZ_2M))
+ pt_count++;
+
+ ret = panthor_vm_op_ctx_prealloc_vmas(op_ctx);
+ if (ret)
+ goto err_cleanup;
+
+ if (pt_count) {
+ op_ctx->rsvd_page_tables.pages = kcalloc(pt_count,
+ sizeof(*op_ctx->rsvd_page_tables.pages),
+ GFP_KERNEL);
+ if (!op_ctx->rsvd_page_tables.pages)
+ goto err_cleanup;
+
+ ret = kmem_cache_alloc_bulk(pt_cache, GFP_KERNEL, pt_count,
+ op_ctx->rsvd_page_tables.pages);
+ if (ret != pt_count) {
+ ret = -ENOMEM;
+ goto err_cleanup;
+ }
+ op_ctx->rsvd_page_tables.count = pt_count;
+ }
+
+ return 0;
+
+err_cleanup:
+ panthor_vm_cleanup_op_ctx(op_ctx, vm);
+ return ret;
+}
+
+static void panthor_vm_prepare_sync_only_op_ctx(struct panthor_vm_op_ctx *op_ctx,
+ struct panthor_vm *vm)
+{
+ memset(op_ctx, 0, sizeof(*op_ctx));
+ INIT_LIST_HEAD(&op_ctx->returned_vmas);
+ op_ctx->flags = DRM_PANTHOR_VM_BIND_OP_TYPE_SYNC_ONLY;
+}
+
+/**
+ * panthor_vm_get_bo_for_va() - Get the GEM object mapped at a virtual address
+ * @vm: VM to look into.
+ * @va: Virtual address to search for.
+ * @bo_offset: Offset of the GEM object mapped at this virtual address.
+ * Only valid on success.
+ *
+ * The object returned by this function might no longer be mapped when the
+ * function returns. It's the caller responsibility to ensure there's no
+ * concurrent map/unmap operations making the returned value invalid, or
+ * make sure it doesn't matter if the object is no longer mapped.
+ *
+ * Return: A valid pointer on success, an ERR_PTR() otherwise.
+ */
+struct panthor_gem_object *
+panthor_vm_get_bo_for_va(struct panthor_vm *vm, u64 va, u64 *bo_offset)
+{
+ struct panthor_gem_object *bo = ERR_PTR(-ENOENT);
+ struct drm_gpuva *gpuva;
+ struct panthor_vma *vma;
+
+ /* Take the VM lock to prevent concurrent map/unmap operations. */
+ mutex_lock(&vm->op_lock);
+ gpuva = drm_gpuva_find_first(&vm->base, va, 1);
+ vma = gpuva ? container_of(gpuva, struct panthor_vma, base) : NULL;
+ if (vma && vma->base.gem.obj) {
+ drm_gem_object_get(vma->base.gem.obj);
+ bo = to_panthor_bo(vma->base.gem.obj);
+ *bo_offset = vma->base.gem.offset + (va - vma->base.va.addr);
+ }
+ mutex_unlock(&vm->op_lock);
+
+ return bo;
+}
+
+#define PANTHOR_VM_MIN_KERNEL_VA_SIZE SZ_256M
+
+static u64
+panthor_vm_create_get_user_va_range(const struct drm_panthor_vm_create *args,
+ u64 full_va_range)
+{
+ u64 user_va_range;
+
+ /* Make sure we have a minimum amount of VA space for kernel objects. */
+ if (full_va_range < PANTHOR_VM_MIN_KERNEL_VA_SIZE)
+ return 0;
+
+ if (args->user_va_range) {
+ /* Use the user provided value if != 0. */
+ user_va_range = args->user_va_range;
+ } else if (TASK_SIZE_OF(current) < full_va_range) {
+ /* If the task VM size is smaller than the GPU VA range, pick this
+ * as our default user VA range, so userspace can CPU/GPU map buffers
+ * at the same address.
+ */
+ user_va_range = TASK_SIZE_OF(current);
+ } else {
+ /* If the GPU VA range is smaller than the task VM size, we
+ * just have to live with the fact we won't be able to map
+ * all buffers at the same GPU/CPU address.
+ *
+ * If the GPU VA range is bigger than 4G (more than 32-bit of
+ * VA), we split the range in two, and assign half of it to
+ * the user and the other half to the kernel, if it's not, we
+ * keep the kernel VA space as small as possible.
+ */
+ user_va_range = full_va_range > SZ_4G ?
+ full_va_range / 2 :
+ full_va_range - PANTHOR_VM_MIN_KERNEL_VA_SIZE;
+ }
+
+ if (full_va_range - PANTHOR_VM_MIN_KERNEL_VA_SIZE < user_va_range)
+ user_va_range = full_va_range - PANTHOR_VM_MIN_KERNEL_VA_SIZE;
+
+ return user_va_range;
+}
+
+#define PANTHOR_VM_CREATE_FLAGS 0
+
+static int
+panthor_vm_create_check_args(const struct panthor_device *ptdev,
+ const struct drm_panthor_vm_create *args,
+ u64 *kernel_va_start, u64 *kernel_va_range)
+{
+ u32 va_bits = GPU_MMU_FEATURES_VA_BITS(ptdev->gpu_info.mmu_features);
+ u64 full_va_range = 1ull << va_bits;
+ u64 user_va_range;
+
+ if (args->flags & ~PANTHOR_VM_CREATE_FLAGS)
+ return -EINVAL;
+
+ user_va_range = panthor_vm_create_get_user_va_range(args, full_va_range);
+ if (!user_va_range || (args->user_va_range && args->user_va_range > user_va_range))
+ return -EINVAL;
+
+ /* Pick a kernel VA range that's a power of two, to have a clear split. */
+ *kernel_va_range = rounddown_pow_of_two(full_va_range - user_va_range);
+ *kernel_va_start = full_va_range - *kernel_va_range;
+ return 0;
+}
+
+/*
+ * Only 32 VMs per open file. If that becomes a limiting factor, we can
+ * increase this number.
+ */
+#define PANTHOR_MAX_VMS_PER_FILE 32
+
+/**
+ * panthor_vm_pool_create_vm() - Create a VM
+ * @pool: The VM to create this VM on.
+ * @kernel_va_start: Start of the region reserved for kernel objects.
+ * @kernel_va_range: Size of the region reserved for kernel objects.
+ *
+ * Return: a positive VM ID on success, a negative error code otherwise.
+ */
+int panthor_vm_pool_create_vm(struct panthor_device *ptdev,
+ struct panthor_vm_pool *pool,
+ struct drm_panthor_vm_create *args)
+{
+ u64 kernel_va_start, kernel_va_range;
+ struct panthor_vm *vm;
+ int ret;
+ u32 id;
+
+ ret = panthor_vm_create_check_args(ptdev, args, &kernel_va_start, &kernel_va_range);
+ if (ret)
+ return ret;
+
+ vm = panthor_vm_create(ptdev, false, kernel_va_start, kernel_va_range,
+ kernel_va_start, kernel_va_range);
+ if (IS_ERR(vm))
+ return PTR_ERR(vm);
+
+ ret = xa_alloc(&pool->xa, &id, vm,
+ XA_LIMIT(1, PANTHOR_MAX_VMS_PER_FILE), GFP_KERNEL);
+
+ if (ret) {
+ panthor_vm_put(vm);
+ return ret;
+ }
+
+ args->user_va_range = kernel_va_start;
+ return id;
+}
+
+static void panthor_vm_destroy(struct panthor_vm *vm)
+{
+ if (!vm)
+ return;
+
+ vm->destroyed = true;
+
+ mutex_lock(&vm->heaps.lock);
+ panthor_heap_pool_destroy(vm->heaps.pool);
+ vm->heaps.pool = NULL;
+ mutex_unlock(&vm->heaps.lock);
+
+ drm_WARN_ON(&vm->ptdev->base,
+ panthor_vm_unmap_range(vm, vm->base.mm_start, vm->base.mm_range));
+ panthor_vm_put(vm);
+}
+
+/**
+ * panthor_vm_pool_destroy_vm() - Destroy a VM.
+ * @pool: VM pool.
+ * @handle: VM handle.
+ *
+ * This function doesn't free the VM object or its resources, it just kills
+ * all mappings, and makes sure nothing can be mapped after that point.
+ *
+ * If there was any active jobs at the time this function is called, these
+ * jobs should experience page faults and be killed as a result.
+ *
+ * The VM resources are freed when the last reference on the VM object is
+ * dropped.
+ */
+int panthor_vm_pool_destroy_vm(struct panthor_vm_pool *pool, u32 handle)
+{
+ struct panthor_vm *vm;
+
+ vm = xa_erase(&pool->xa, handle);
+
+ panthor_vm_destroy(vm);
+
+ return vm ? 0 : -EINVAL;
+}
+
+/**
+ * panthor_vm_pool_get_vm() - Retrieve VM object bound to a VM handle
+ * @pool: VM pool to check.
+ * @handle: Handle of the VM to retrieve.
+ *
+ * Return: A valid pointer if the VM exists, NULL otherwise.
+ */
+struct panthor_vm *
+panthor_vm_pool_get_vm(struct panthor_vm_pool *pool, u32 handle)
+{
+ struct panthor_vm *vm;
+
+ vm = panthor_vm_get(xa_load(&pool->xa, handle));
+
+ return vm;
+}
+
+/**
+ * panthor_vm_pool_destroy() - Destroy a VM pool.
+ * @pfile: File.
+ *
+ * Destroy all VMs in the pool, and release the pool resources.
+ *
+ * Note that VMs can outlive the pool they were created from if other
+ * objects hold a reference to there VMs.
+ */
+void panthor_vm_pool_destroy(struct panthor_file *pfile)
+{
+ struct panthor_vm *vm;
+ unsigned long i;
+
+ if (!pfile->vms)
+ return;
+
+ xa_for_each(&pfile->vms->xa, i, vm)
+ panthor_vm_destroy(vm);
+
+ xa_destroy(&pfile->vms->xa);
+ kfree(pfile->vms);
+}
+
+/**
+ * panthor_vm_pool_create() - Create a VM pool
+ * @pfile: File.
+ *
+ * Return: 0 on success, a negative error code otherwise.
+ */
+int panthor_vm_pool_create(struct panthor_file *pfile)
+{
+ pfile->vms = kzalloc(sizeof(*pfile->vms), GFP_KERNEL);
+ if (!pfile->vms)
+ return -ENOMEM;
+
+ xa_init_flags(&pfile->vms->xa, XA_FLAGS_ALLOC1);
+ return 0;
+}
+
+/* dummy TLB ops, the real TLB flush happens in panthor_vm_flush_range() */
+static void mmu_tlb_flush_all(void *cookie)
+{
+}
+
+static void mmu_tlb_flush_walk(unsigned long iova, size_t size, size_t granule, void *cookie)
+{
+}
+
+static const struct iommu_flush_ops mmu_tlb_ops = {
+ .tlb_flush_all = mmu_tlb_flush_all,
+ .tlb_flush_walk = mmu_tlb_flush_walk,
+};
+
+static const char *access_type_name(struct panthor_device *ptdev,
+ u32 fault_status)
+{
+ switch (fault_status & AS_FAULTSTATUS_ACCESS_TYPE_MASK) {
+ case AS_FAULTSTATUS_ACCESS_TYPE_ATOMIC:
+ return "ATOMIC";
+ case AS_FAULTSTATUS_ACCESS_TYPE_READ:
+ return "READ";
+ case AS_FAULTSTATUS_ACCESS_TYPE_WRITE:
+ return "WRITE";
+ case AS_FAULTSTATUS_ACCESS_TYPE_EX:
+ return "EXECUTE";
+ default:
+ drm_WARN_ON(&ptdev->base, 1);
+ return NULL;
+ }
+}
+
+static void panthor_mmu_irq_handler(struct panthor_device *ptdev, u32 status)
+{
+ bool has_unhandled_faults = false;
+
+ status = panthor_mmu_fault_mask(ptdev, status);
+ while (status) {
+ u32 as = ffs(status | (status >> 16)) - 1;
+ u32 mask = panthor_mmu_as_fault_mask(ptdev, as);
+ u32 new_int_mask;
+ u64 addr;
+ u32 fault_status;
+ u32 exception_type;
+ u32 access_type;
+ u32 source_id;
+
+ fault_status = gpu_read(ptdev, AS_FAULTSTATUS(as));
+ addr = gpu_read(ptdev, AS_FAULTADDRESS_LO(as));
+ addr |= (u64)gpu_read(ptdev, AS_FAULTADDRESS_HI(as)) << 32;
+
+ /* decode the fault status */
+ exception_type = fault_status & 0xFF;
+ access_type = (fault_status >> 8) & 0x3;
+ source_id = (fault_status >> 16);
+
+ mutex_lock(&ptdev->mmu->as.slots_lock);
+
+ ptdev->mmu->as.faulty_mask |= mask;
+ new_int_mask =
+ panthor_mmu_fault_mask(ptdev, ~ptdev->mmu->as.faulty_mask);
+
+ /* terminal fault, print info about the fault */
+ drm_err(&ptdev->base,
+ "Unhandled Page fault in AS%d at VA 0x%016llX\n"
+ "raw fault status: 0x%X\n"
+ "decoded fault status: %s\n"
+ "exception type 0x%X: %s\n"
+ "access type 0x%X: %s\n"
+ "source id 0x%X\n",
+ as, addr,
+ fault_status,
+ (fault_status & (1 << 10) ? "DECODER FAULT" : "SLAVE FAULT"),
+ exception_type, panthor_exception_name(ptdev, exception_type),
+ access_type, access_type_name(ptdev, fault_status),
+ source_id);
+
+ /* Ignore MMU interrupts on this AS until it's been
+ * re-enabled.
+ */
+ ptdev->mmu->irq.mask = new_int_mask;
+ gpu_write(ptdev, MMU_INT_MASK, new_int_mask);
+
+ if (ptdev->mmu->as.slots[as].vm)
+ ptdev->mmu->as.slots[as].vm->unhandled_fault = true;
+
+ /* Disable the MMU to kill jobs on this AS. */
+ panthor_mmu_as_disable(ptdev, as);
+ mutex_unlock(&ptdev->mmu->as.slots_lock);
+
+ status &= ~mask;
+ has_unhandled_faults = true;
+ }
+
+ if (has_unhandled_faults)
+ panthor_sched_report_mmu_fault(ptdev);
+}
+PANTHOR_IRQ_HANDLER(mmu, MMU, panthor_mmu_irq_handler);
+
+/**
+ * panthor_mmu_suspend() - Suspend the MMU logic
+ * @ptdev: Device.
+ *
+ * All we do here is de-assign the AS slots on all active VMs, so things
+ * get flushed to the main memory, and no further access to these VMs are
+ * possible.
+ *
+ * We also suspend the MMU IRQ.
+ */
+void panthor_mmu_suspend(struct panthor_device *ptdev)
+{
+ mutex_lock(&ptdev->mmu->as.slots_lock);
+ for (u32 i = 0; i < ARRAY_SIZE(ptdev->mmu->as.slots); i++) {
+ struct panthor_vm *vm = ptdev->mmu->as.slots[i].vm;
+
+ if (vm) {
+ drm_WARN_ON(&ptdev->base, panthor_mmu_as_disable(ptdev, i));
+ panthor_vm_release_as_locked(vm);
+ }
+ }
+ mutex_unlock(&ptdev->mmu->as.slots_lock);
+
+ panthor_mmu_irq_suspend(&ptdev->mmu->irq);
+}
+
+/**
+ * panthor_mmu_resume() - Resume the MMU logic
+ * @ptdev: Device.
+ *
+ * Resume the IRQ.
+ *
+ * We don't re-enable previously active VMs. We assume other parts of the
+ * driver will call panthor_vm_active() on the VMs they intend to use.
+ */
+void panthor_mmu_resume(struct panthor_device *ptdev)
+{
+ mutex_lock(&ptdev->mmu->as.slots_lock);
+ ptdev->mmu->as.alloc_mask = 0;
+ ptdev->mmu->as.faulty_mask = 0;
+ mutex_unlock(&ptdev->mmu->as.slots_lock);
+
+ panthor_mmu_irq_resume(&ptdev->mmu->irq, panthor_mmu_fault_mask(ptdev, ~0));
+}
+
+/**
+ * panthor_mmu_pre_reset() - Prepare for a reset
+ * @ptdev: Device.
+ *
+ * Suspend the IRQ, and make sure all VM_BIND queues are stopped, so we
+ * don't get asked to do a VM operation while the GPU is down.
+ *
+ * We don't cleanly shutdown the AS slots here, because the reset might
+ * come from an AS_ACTIVE_BIT stuck situation.
+ */
+void panthor_mmu_pre_reset(struct panthor_device *ptdev)
+{
+ struct panthor_vm *vm;
+
+ panthor_mmu_irq_suspend(&ptdev->mmu->irq);
+
+ mutex_lock(&ptdev->mmu->vm.lock);
+ ptdev->mmu->vm.reset_in_progress = true;
+ list_for_each_entry(vm, &ptdev->mmu->vm.list, node)
+ panthor_vm_stop(vm);
+ mutex_unlock(&ptdev->mmu->vm.lock);
+}
+
+/**
+ * panthor_mmu_post_reset() - Restore things after a reset
+ * @ptdev: Device.
+ *
+ * Put the MMU logic back in action after a reset. That implies resuming the
+ * IRQ and re-enabling the VM_BIND queues.
+ */
+void panthor_mmu_post_reset(struct panthor_device *ptdev)
+{
+ struct panthor_vm *vm;
+
+ mutex_lock(&ptdev->mmu->as.slots_lock);
+
+ /* Now that the reset is effective, we can assume that none of the
+ * AS slots are setup, and clear the faulty flags too.
+ */
+ ptdev->mmu->as.alloc_mask = 0;
+ ptdev->mmu->as.faulty_mask = 0;
+
+ for (u32 i = 0; i < ARRAY_SIZE(ptdev->mmu->as.slots); i++) {
+ struct panthor_vm *vm = ptdev->mmu->as.slots[i].vm;
+
+ if (vm)
+ panthor_vm_release_as_locked(vm);
+ }
+
+ mutex_unlock(&ptdev->mmu->as.slots_lock);
+
+ panthor_mmu_irq_resume(&ptdev->mmu->irq, panthor_mmu_fault_mask(ptdev, ~0));
+
+ /* Restart the VM_BIND queues. */
+ mutex_lock(&ptdev->mmu->vm.lock);
+ list_for_each_entry(vm, &ptdev->mmu->vm.list, node) {
+ panthor_vm_start(vm);
+ }
+ ptdev->mmu->vm.reset_in_progress = false;
+ mutex_unlock(&ptdev->mmu->vm.lock);
+}
+
+static void panthor_vm_free(struct drm_gpuvm *gpuvm)
+{
+ struct panthor_vm *vm = container_of(gpuvm, struct panthor_vm, base);
+ struct panthor_device *ptdev = vm->ptdev;
+
+ mutex_lock(&vm->heaps.lock);
+ if (drm_WARN_ON(&ptdev->base, vm->heaps.pool))
+ panthor_heap_pool_destroy(vm->heaps.pool);
+ mutex_unlock(&vm->heaps.lock);
+ mutex_destroy(&vm->heaps.lock);
+
+ mutex_lock(&ptdev->mmu->vm.lock);
+ list_del(&vm->node);
+ /* Restore the scheduler state so we can call drm_sched_entity_destroy()
+ * and drm_sched_fini(). If get there, that means we have no job left
+ * and no new jobs can be queued, so we can start the scheduler without
+ * risking interfering with the reset.
+ */
+ if (ptdev->mmu->vm.reset_in_progress)
+ panthor_vm_start(vm);
+ mutex_unlock(&ptdev->mmu->vm.lock);
+
+ drm_sched_entity_destroy(&vm->entity);
+ drm_sched_fini(&vm->sched);
+
+ mutex_lock(&ptdev->mmu->as.slots_lock);
+ if (vm->as.id >= 0) {
+ int cookie;
+
+ if (drm_dev_enter(&ptdev->base, &cookie)) {
+ panthor_mmu_as_disable(ptdev, vm->as.id);
+ drm_dev_exit(cookie);
+ }
+
+ ptdev->mmu->as.slots[vm->as.id].vm = NULL;
+ clear_bit(vm->as.id, &ptdev->mmu->as.alloc_mask);
+ list_del(&vm->as.lru_node);
+ }
+ mutex_unlock(&ptdev->mmu->as.slots_lock);
+
+ free_io_pgtable_ops(vm->pgtbl_ops);
+
+ drm_mm_takedown(&vm->mm);
+ kfree(vm);
+}
+
+/**
+ * panthor_vm_put() - Release a reference on a VM
+ * @vm: VM to release the reference on. Can be NULL.
+ */
+void panthor_vm_put(struct panthor_vm *vm)
+{
+ drm_gpuvm_put(vm ? &vm->base : NULL);
+}
+
+/**
+ * panthor_vm_get() - Get a VM reference
+ * @vm: VM to get the reference on. Can be NULL.
+ *
+ * Return: @vm value.
+ */
+struct panthor_vm *panthor_vm_get(struct panthor_vm *vm)
+{
+ if (vm)
+ drm_gpuvm_get(&vm->base);
+
+ return vm;
+}
+
+/**
+ * panthor_vm_get_heap_pool() - Get the heap pool attached to a VM
+ * @vm: VM to query the heap pool on.
+ * @create: True if the heap pool should be created when it doesn't exist.
+ *
+ * Heap pools are per-VM. This function allows one to retrieve the heap pool
+ * attached to a VM.
+ *
+ * If no heap pool exists yet, and @create is true, we create one.
+ *
+ * The returned panthor_heap_pool should be released with panthor_heap_pool_put().
+ *
+ * Return: A valid pointer on success, an ERR_PTR() otherwise.
+ */
+struct panthor_heap_pool *panthor_vm_get_heap_pool(struct panthor_vm *vm, bool create)
+{
+ struct panthor_heap_pool *pool;
+
+ mutex_lock(&vm->heaps.lock);
+ if (!vm->heaps.pool && create) {
+ if (vm->destroyed)
+ pool = ERR_PTR(-EINVAL);
+ else
+ pool = panthor_heap_pool_create(vm->ptdev, vm);
+
+ if (!IS_ERR(pool))
+ vm->heaps.pool = panthor_heap_pool_get(pool);
+ } else {
+ pool = panthor_heap_pool_get(vm->heaps.pool);
+ }
+ mutex_unlock(&vm->heaps.lock);
+
+ return pool;
+}
+
+static u64 mair_to_memattr(u64 mair)
+{
+ u64 memattr = 0;
+ u32 i;
+
+ for (i = 0; i < 8; i++) {
+ u8 in_attr = mair >> (8 * i), out_attr;
+ u8 outer = in_attr >> 4, inner = in_attr & 0xf;
+
+ /* For caching to be enabled, inner and outer caching policy
+ * have to be both write-back, if one of them is write-through
+ * or non-cacheable, we just choose non-cacheable. Device
+ * memory is also translated to non-cacheable.
+ */
+ if (!(outer & 3) || !(outer & 4) || !(inner & 4)) {
+ out_attr = AS_MEMATTR_AARCH64_INNER_OUTER_NC |
+ AS_MEMATTR_AARCH64_SH_MIDGARD_INNER |
+ AS_MEMATTR_AARCH64_INNER_ALLOC_EXPL(false, false);
+ } else {
+ /* Use SH_CPU_INNER mode so SH_IS, which is used when
+ * IOMMU_CACHE is set, actually maps to the standard
+ * definition of inner-shareable and not Mali's
+ * internal-shareable mode.
+ */
+ out_attr = AS_MEMATTR_AARCH64_INNER_OUTER_WB |
+ AS_MEMATTR_AARCH64_SH_CPU_INNER |
+ AS_MEMATTR_AARCH64_INNER_ALLOC_EXPL(inner & 1, inner & 2);
+ }
+
+ memattr |= (u64)out_attr << (8 * i);
+ }
+
+ return memattr;
+}
+
+static void panthor_vma_link(struct panthor_vm *vm,
+ struct panthor_vma *vma,
+ struct drm_gpuvm_bo *vm_bo)
+{
+ struct panthor_gem_object *bo = to_panthor_bo(vma->base.gem.obj);
+
+ mutex_lock(&bo->gpuva_list_lock);
+ drm_gpuva_link(&vma->base, vm_bo);
+ drm_WARN_ON(&vm->ptdev->base, drm_gpuvm_bo_put(vm_bo));
+ mutex_unlock(&bo->gpuva_list_lock);
+}
+
+static void panthor_vma_unlink(struct panthor_vm *vm,
+ struct panthor_vma *vma)
+{
+ struct panthor_gem_object *bo = to_panthor_bo(vma->base.gem.obj);
+ struct drm_gpuvm_bo *vm_bo = drm_gpuvm_bo_get(vma->base.vm_bo);
+
+ mutex_lock(&bo->gpuva_list_lock);
+ drm_gpuva_unlink(&vma->base);
+ mutex_unlock(&bo->gpuva_list_lock);
+
+ /* drm_gpuva_unlink() release the vm_bo, but we manually retained it
+ * when entering this function, so we can implement deferred VMA
+ * destruction. Re-assign it here.
+ */
+ vma->base.vm_bo = vm_bo;
+ list_add_tail(&vma->node, &vm->op_ctx->returned_vmas);
+}
+
+static void panthor_vma_init(struct panthor_vma *vma, u32 flags)
+{
+ INIT_LIST_HEAD(&vma->node);
+ vma->flags = flags;
+}
+
+#define PANTHOR_VM_MAP_FLAGS \
+ (DRM_PANTHOR_VM_BIND_OP_MAP_READONLY | \
+ DRM_PANTHOR_VM_BIND_OP_MAP_NOEXEC | \
+ DRM_PANTHOR_VM_BIND_OP_MAP_UNCACHED)
+
+static int panthor_gpuva_sm_step_map(struct drm_gpuva_op *op, void *priv)
+{
+ struct panthor_vm *vm = priv;
+ struct panthor_vm_op_ctx *op_ctx = vm->op_ctx;
+ struct panthor_vma *vma = panthor_vm_op_ctx_get_vma(op_ctx);
+ int ret;
+
+ if (!vma)
+ return -EINVAL;
+
+ panthor_vma_init(vma, op_ctx->flags & PANTHOR_VM_MAP_FLAGS);
+
+ ret = panthor_vm_map_pages(vm, op->map.va.addr, flags_to_prot(vma->flags),
+ op_ctx->map.sgt, op->map.gem.offset,
+ op->map.va.range);
+ if (ret)
+ return ret;
+
+ /* Ref owned by the mapping now, clear the obj field so we don't release the
+ * pinning/obj ref behind GPUVA's back.
+ */
+ drm_gpuva_map(&vm->base, &vma->base, &op->map);
+ panthor_vma_link(vm, vma, op_ctx->map.vm_bo);
+ op_ctx->map.vm_bo = NULL;
+ return 0;
+}
+
+static int panthor_gpuva_sm_step_remap(struct drm_gpuva_op *op,
+ void *priv)
+{
+ struct panthor_vma *unmap_vma = container_of(op->remap.unmap->va, struct panthor_vma, base);
+ struct panthor_vm *vm = priv;
+ struct panthor_vm_op_ctx *op_ctx = vm->op_ctx;
+ struct panthor_vma *prev_vma = NULL, *next_vma = NULL;
+ u64 unmap_start, unmap_range;
+ int ret;
+
+ drm_gpuva_op_remap_to_unmap_range(&op->remap, &unmap_start, &unmap_range);
+ ret = panthor_vm_unmap_pages(vm, unmap_start, unmap_range);
+ if (ret)
+ return ret;
+
+ if (op->remap.prev) {
+ prev_vma = panthor_vm_op_ctx_get_vma(op_ctx);
+ panthor_vma_init(prev_vma, unmap_vma->flags);
+ }
+
+ if (op->remap.next) {
+ next_vma = panthor_vm_op_ctx_get_vma(op_ctx);
+ panthor_vma_init(next_vma, unmap_vma->flags);
+ }
+
+ drm_gpuva_remap(prev_vma ? &prev_vma->base : NULL,
+ next_vma ? &next_vma->base : NULL,
+ &op->remap);
+
+ if (prev_vma) {
+ /* panthor_vma_link() transfers the vm_bo ownership to
+ * the VMA object. Since the vm_bo we're passing is still
+ * owned by the old mapping which will be released when this
+ * mapping is destroyed, we need to grab a ref here.
+ */
+ panthor_vma_link(vm, prev_vma,
+ drm_gpuvm_bo_get(op->remap.unmap->va->vm_bo));
+ }
+
+ if (next_vma) {
+ panthor_vma_link(vm, next_vma,
+ drm_gpuvm_bo_get(op->remap.unmap->va->vm_bo));
+ }
+
+ panthor_vma_unlink(vm, unmap_vma);
+ return 0;
+}
+
+static int panthor_gpuva_sm_step_unmap(struct drm_gpuva_op *op,
+ void *priv)
+{
+ struct panthor_vma *unmap_vma = container_of(op->unmap.va, struct panthor_vma, base);
+ struct panthor_vm *vm = priv;
+ int ret;
+
+ ret = panthor_vm_unmap_pages(vm, unmap_vma->base.va.addr,
+ unmap_vma->base.va.range);
+ if (drm_WARN_ON(&vm->ptdev->base, ret))
+ return ret;
+
+ drm_gpuva_unmap(&op->unmap);
+ panthor_vma_unlink(vm, unmap_vma);
+ return 0;
+}
+
+static const struct drm_gpuvm_ops panthor_gpuvm_ops = {
+ .vm_free = panthor_vm_free,
+ .sm_step_map = panthor_gpuva_sm_step_map,
+ .sm_step_remap = panthor_gpuva_sm_step_remap,
+ .sm_step_unmap = panthor_gpuva_sm_step_unmap,
+};
+
+/**
+ * panthor_vm_resv() - Get the dma_resv object attached to a VM.
+ * @vm: VM to get the dma_resv of.
+ *
+ * Return: A dma_resv object.
+ */
+struct dma_resv *panthor_vm_resv(struct panthor_vm *vm)
+{
+ return drm_gpuvm_resv(&vm->base);
+}
+
+struct drm_gem_object *panthor_vm_root_gem(struct panthor_vm *vm)
+{
+ if (!vm)
+ return NULL;
+
+ return vm->base.r_obj;
+}
+
+static int
+panthor_vm_exec_op(struct panthor_vm *vm, struct panthor_vm_op_ctx *op,
+ bool flag_vm_unusable_on_failure)
+{
+ u32 op_type = op->flags & DRM_PANTHOR_VM_BIND_OP_TYPE_MASK;
+ int ret;
+
+ if (op_type == DRM_PANTHOR_VM_BIND_OP_TYPE_SYNC_ONLY)
+ return 0;
+
+ mutex_lock(&vm->op_lock);
+ vm->op_ctx = op;
+ switch (op_type) {
+ case DRM_PANTHOR_VM_BIND_OP_TYPE_MAP:
+ if (vm->unusable) {
+ ret = -EINVAL;
+ break;
+ }
+
+ ret = drm_gpuvm_sm_map(&vm->base, vm, op->va.addr, op->va.range,
+ op->map.vm_bo->obj, op->map.bo_offset);
+ break;
+
+ case DRM_PANTHOR_VM_BIND_OP_TYPE_UNMAP:
+ ret = drm_gpuvm_sm_unmap(&vm->base, vm, op->va.addr, op->va.range);
+ break;
+
+ default:
+ ret = -EINVAL;
+ break;
+ }
+
+ if (ret && flag_vm_unusable_on_failure)
+ vm->unusable = true;
+
+ vm->op_ctx = NULL;
+ mutex_unlock(&vm->op_lock);
+
+ return ret;
+}
+
+static struct dma_fence *
+panthor_vm_bind_run_job(struct drm_sched_job *sched_job)
+{
+ struct panthor_vm_bind_job *job = container_of(sched_job, struct panthor_vm_bind_job, base);
+ bool cookie;
+ int ret;
+
+ /* Not only we report an error whose result is propagated to the
+ * drm_sched finished fence, but we also flag the VM as unusable, because
+ * a failure in the async VM_BIND results in an inconsistent state. VM needs
+ * to be destroyed and recreated.
+ */
+ cookie = dma_fence_begin_signalling();
+ ret = panthor_vm_exec_op(job->vm, &job->ctx, true);
+ dma_fence_end_signalling(cookie);
+
+ return ret ? ERR_PTR(ret) : NULL;
+}
+
+static void panthor_vm_bind_job_release(struct kref *kref)
+{
+ struct panthor_vm_bind_job *job = container_of(kref, struct panthor_vm_bind_job, refcount);
+
+ if (job->base.s_fence)
+ drm_sched_job_cleanup(&job->base);
+
+ panthor_vm_cleanup_op_ctx(&job->ctx, job->vm);
+ panthor_vm_put(job->vm);
+ kfree(job);
+}
+
+/**
+ * panthor_vm_bind_job_put() - Release a VM_BIND job reference
+ * @sched_job: Job to release the reference on.
+ */
+void panthor_vm_bind_job_put(struct drm_sched_job *sched_job)
+{
+ struct panthor_vm_bind_job *job =
+ container_of(sched_job, struct panthor_vm_bind_job, base);
+
+ if (sched_job)
+ kref_put(&job->refcount, panthor_vm_bind_job_release);
+}
+
+static void
+panthor_vm_bind_free_job(struct drm_sched_job *sched_job)
+{
+ struct panthor_vm_bind_job *job =
+ container_of(sched_job, struct panthor_vm_bind_job, base);
+
+ drm_sched_job_cleanup(sched_job);
+
+ /* Do the heavy cleanups asynchronously, so we're out of the
+ * dma-signaling path and can acquire dma-resv locks safely.
+ */
+ queue_work(panthor_cleanup_wq, &job->cleanup_op_ctx_work);
+}
+
+static enum drm_gpu_sched_stat
+panthor_vm_bind_timedout_job(struct drm_sched_job *sched_job)
+{
+ WARN(1, "VM_BIND ops are synchronous for now, there should be no timeout!");
+ return DRM_GPU_SCHED_STAT_NOMINAL;
+}
+
+static const struct drm_sched_backend_ops panthor_vm_bind_ops = {
+ .run_job = panthor_vm_bind_run_job,
+ .free_job = panthor_vm_bind_free_job,
+ .timedout_job = panthor_vm_bind_timedout_job,
+};
+
+/**
+ * panthor_vm_create() - Create a VM
+ * @ptdev: Device.
+ * @for_mcu: True if this is the FW MCU VM.
+ * @kernel_va_start: Start of the range reserved for kernel BO mapping.
+ * @kernel_va_size: Size of the range reserved for kernel BO mapping.
+ * @auto_kernel_va_start: Start of the auto-VA kernel range.
+ * @auto_kernel_va_size: Size of the auto-VA kernel range.
+ *
+ * Return: A valid pointer on success, an ERR_PTR() otherwise.
+ */
+struct panthor_vm *
+panthor_vm_create(struct panthor_device *ptdev, bool for_mcu,
+ u64 kernel_va_start, u64 kernel_va_size,
+ u64 auto_kernel_va_start, u64 auto_kernel_va_size)
+{
+ u32 va_bits = GPU_MMU_FEATURES_VA_BITS(ptdev->gpu_info.mmu_features);
+ u32 pa_bits = GPU_MMU_FEATURES_PA_BITS(ptdev->gpu_info.mmu_features);
+ u64 full_va_range = 1ull << va_bits;
+ struct drm_gem_object *dummy_gem;
+ struct drm_gpu_scheduler *sched;
+ struct io_pgtable_cfg pgtbl_cfg;
+ u64 mair, min_va, va_range;
+ struct panthor_vm *vm;
+ int ret;
+
+ vm = kzalloc(sizeof(*vm), GFP_KERNEL);
+ if (!vm)
+ return ERR_PTR(-ENOMEM);
+
+ /* We allocate a dummy GEM for the VM. */
+ dummy_gem = drm_gpuvm_resv_object_alloc(&ptdev->base);
+ if (!dummy_gem) {
+ ret = -ENOMEM;
+ goto err_free_vm;
+ }
+
+ mutex_init(&vm->heaps.lock);
+ vm->for_mcu = for_mcu;
+ vm->ptdev = ptdev;
+ mutex_init(&vm->op_lock);
+
+ if (for_mcu) {
+ /* CSF MCU is a cortex M7, and can only address 4G */
+ min_va = 0;
+ va_range = SZ_4G;
+ } else {
+ min_va = 0;
+ va_range = full_va_range;
+ }
+
+ mutex_init(&vm->mm_lock);
+ drm_mm_init(&vm->mm, kernel_va_start, kernel_va_size);
+ vm->kernel_auto_va.start = auto_kernel_va_start;
+ vm->kernel_auto_va.end = vm->kernel_auto_va.start + auto_kernel_va_size - 1;
+
+ INIT_LIST_HEAD(&vm->node);
+ INIT_LIST_HEAD(&vm->as.lru_node);
+ vm->as.id = -1;
+ refcount_set(&vm->as.active_cnt, 0);
+
+ pgtbl_cfg = (struct io_pgtable_cfg) {
+ .pgsize_bitmap = SZ_4K | SZ_2M,
+ .ias = va_bits,
+ .oas = pa_bits,
+ .coherent_walk = ptdev->coherent,
+ .tlb = &mmu_tlb_ops,
+ .iommu_dev = ptdev->base.dev,
+ .alloc = alloc_pt,
+ .free = free_pt,
+ };
+
+ vm->pgtbl_ops = alloc_io_pgtable_ops(ARM_64_LPAE_S1, &pgtbl_cfg, vm);
+ if (!vm->pgtbl_ops) {
+ ret = -EINVAL;
+ goto err_mm_takedown;
+ }
+
+ /* Bind operations are synchronous for now, no timeout needed. */
+ ret = drm_sched_init(&vm->sched, &panthor_vm_bind_ops, ptdev->mmu->vm.wq,
+ 1, 1, 0,
+ MAX_SCHEDULE_TIMEOUT, NULL, NULL,
+ "panthor-vm-bind", ptdev->base.dev);
+ if (ret)
+ goto err_free_io_pgtable;
+
+ sched = &vm->sched;
+ ret = drm_sched_entity_init(&vm->entity, 0, &sched, 1, NULL);
+ if (ret)
+ goto err_sched_fini;
+
+ mair = io_pgtable_ops_to_pgtable(vm->pgtbl_ops)->cfg.arm_lpae_s1_cfg.mair;
+ vm->memattr = mair_to_memattr(mair);
+
+ mutex_lock(&ptdev->mmu->vm.lock);
+ list_add_tail(&vm->node, &ptdev->mmu->vm.list);
+
+ /* If a reset is in progress, stop the scheduler. */
+ if (ptdev->mmu->vm.reset_in_progress)
+ panthor_vm_stop(vm);
+ mutex_unlock(&ptdev->mmu->vm.lock);
+
+ /* We intentionally leave the reserved range to zero, because we want kernel VMAs
+ * to be handled the same way user VMAs are.
+ */
+ drm_gpuvm_init(&vm->base, for_mcu ? "panthor-MCU-VM" : "panthor-GPU-VM",
+ DRM_GPUVM_RESV_PROTECTED, &ptdev->base, dummy_gem,
+ min_va, va_range, 0, 0, &panthor_gpuvm_ops);
+ drm_gem_object_put(dummy_gem);
+ return vm;
+
+err_sched_fini:
+ drm_sched_fini(&vm->sched);
+
+err_free_io_pgtable:
+ free_io_pgtable_ops(vm->pgtbl_ops);
+
+err_mm_takedown:
+ drm_mm_takedown(&vm->mm);
+ drm_gem_object_put(dummy_gem);
+
+err_free_vm:
+ kfree(vm);
+ return ERR_PTR(ret);
+}
+
+static int
+panthor_vm_bind_prepare_op_ctx(struct drm_file *file,
+ struct panthor_vm *vm,
+ const struct drm_panthor_vm_bind_op *op,
+ struct panthor_vm_op_ctx *op_ctx)
+{
+ struct drm_gem_object *gem;
+ int ret;
+
+ /* Aligned on page size. */
+ if ((op->va | op->size) & ~PAGE_MASK)
+ return -EINVAL;
+
+ switch (op->flags & DRM_PANTHOR_VM_BIND_OP_TYPE_MASK) {
+ case DRM_PANTHOR_VM_BIND_OP_TYPE_MAP:
+ gem = drm_gem_object_lookup(file, op->bo_handle);
+ ret = panthor_vm_prepare_map_op_ctx(op_ctx, vm,
+ gem ? to_panthor_bo(gem) : NULL,
+ op->bo_offset,
+ op->size,
+ op->va,
+ op->flags);
+ drm_gem_object_put(gem);
+ return ret;
+
+ case DRM_PANTHOR_VM_BIND_OP_TYPE_UNMAP:
+ if (op->flags & ~DRM_PANTHOR_VM_BIND_OP_TYPE_MASK)
+ return -EINVAL;
+
+ if (op->bo_handle || op->bo_offset)
+ return -EINVAL;
+
+ return panthor_vm_prepare_unmap_op_ctx(op_ctx, vm, op->va, op->size);
+
+ case DRM_PANTHOR_VM_BIND_OP_TYPE_SYNC_ONLY:
+ if (op->flags & ~DRM_PANTHOR_VM_BIND_OP_TYPE_MASK)
+ return -EINVAL;
+
+ if (op->bo_handle || op->bo_offset)
+ return -EINVAL;
+
+ if (op->va || op->size)
+ return -EINVAL;
+
+ if (!op->syncs.count)
+ return -EINVAL;
+
+ panthor_vm_prepare_sync_only_op_ctx(op_ctx, vm);
+ return 0;
+
+ default:
+ return -EINVAL;
+ }
+}
+
+static void panthor_vm_bind_job_cleanup_op_ctx_work(struct work_struct *work)
+{
+ struct panthor_vm_bind_job *job =
+ container_of(work, struct panthor_vm_bind_job, cleanup_op_ctx_work);
+
+ panthor_vm_bind_job_put(&job->base);
+}
+
+/**
+ * panthor_vm_bind_job_create() - Create a VM_BIND job
+ * @file: File.
+ * @vm: VM targeted by the VM_BIND job.
+ * @op: VM operation data.
+ *
+ * Return: A valid pointer on success, an ERR_PTR() otherwise.
+ */
+struct drm_sched_job *
+panthor_vm_bind_job_create(struct drm_file *file,
+ struct panthor_vm *vm,
+ const struct drm_panthor_vm_bind_op *op)
+{
+ struct panthor_vm_bind_job *job;
+ int ret;
+
+ if (!vm)
+ return ERR_PTR(-EINVAL);
+
+ if (vm->destroyed || vm->unusable)
+ return ERR_PTR(-EINVAL);
+
+ job = kzalloc(sizeof(*job), GFP_KERNEL);
+ if (!job)
+ return ERR_PTR(-ENOMEM);
+
+ ret = panthor_vm_bind_prepare_op_ctx(file, vm, op, &job->ctx);
+ if (ret) {
+ kfree(job);
+ return ERR_PTR(ret);
+ }
+
+ INIT_WORK(&job->cleanup_op_ctx_work, panthor_vm_bind_job_cleanup_op_ctx_work);
+ kref_init(&job->refcount);
+ job->vm = panthor_vm_get(vm);
+
+ ret = drm_sched_job_init(&job->base, &vm->entity, 1, vm);
+ if (ret)
+ goto err_put_job;
+
+ return &job->base;
+
+err_put_job:
+ panthor_vm_bind_job_put(&job->base);
+ return ERR_PTR(ret);
+}
+
+/**
+ * panthor_vm_bind_job_prepare_resvs() - Prepare VM_BIND job dma_resvs
+ * @exec: The locking/preparation context.
+ * @sched_job: The job to prepare resvs on.
+ *
+ * Locks and prepare the VM resv.
+ *
+ * If this is a map operation, locks and prepares the GEM resv.
+ *
+ * Return: 0 on success, a negative error code otherwise.
+ */
+int panthor_vm_bind_job_prepare_resvs(struct drm_exec *exec,
+ struct drm_sched_job *sched_job)
+{
+ struct panthor_vm_bind_job *job = container_of(sched_job, struct panthor_vm_bind_job, base);
+ int ret;
+
+ /* Acquire the VM lock an reserve a slot for this VM bind job. */
+ ret = drm_gpuvm_prepare_vm(&job->vm->base, exec, 1);
+ if (ret)
+ return ret;
+
+ if (job->ctx.map.vm_bo) {
+ /* Lock/prepare the GEM being mapped. */
+ ret = drm_exec_prepare_obj(exec, job->ctx.map.vm_bo->obj, 1);
+ if (ret)
+ return ret;
+ }
+
+ return 0;
+}
+
+/**
+ * panthor_vm_bind_job_update_resvs() - Update the resv objects touched by a job
+ * @exec: drm_exec context.
+ * @sched_job: Job to update the resvs on.
+ */
+void panthor_vm_bind_job_update_resvs(struct drm_exec *exec,
+ struct drm_sched_job *sched_job)
+{
+ struct panthor_vm_bind_job *job = container_of(sched_job, struct panthor_vm_bind_job, base);
+
+ /* Explicit sync => we just register our job finished fence as bookkeep. */
+ drm_gpuvm_resv_add_fence(&job->vm->base, exec,
+ &sched_job->s_fence->finished,
+ DMA_RESV_USAGE_BOOKKEEP,
+ DMA_RESV_USAGE_BOOKKEEP);
+}
+
+void panthor_vm_update_resvs(struct panthor_vm *vm, struct drm_exec *exec,
+ struct dma_fence *fence,
+ enum dma_resv_usage private_usage,
+ enum dma_resv_usage extobj_usage)
+{
+ drm_gpuvm_resv_add_fence(&vm->base, exec, fence, private_usage, extobj_usage);
+}
+
+/**
+ * panthor_vm_bind_exec_sync_op() - Execute a VM_BIND operation synchronously.
+ * @file: File.
+ * @vm: VM targeted by the VM operation.
+ * @op: Data describing the VM operation.
+ *
+ * Return: 0 on success, a negative error code otherwise.
+ */
+int panthor_vm_bind_exec_sync_op(struct drm_file *file,
+ struct panthor_vm *vm,
+ struct drm_panthor_vm_bind_op *op)
+{
+ struct panthor_vm_op_ctx op_ctx;
+ int ret;
+
+ /* No sync objects allowed on synchronous operations. */
+ if (op->syncs.count)
+ return -EINVAL;
+
+ if (!op->size)
+ return 0;
+
+ ret = panthor_vm_bind_prepare_op_ctx(file, vm, op, &op_ctx);
+ if (ret)
+ return ret;
+
+ ret = panthor_vm_exec_op(vm, &op_ctx, false);
+ panthor_vm_cleanup_op_ctx(&op_ctx, vm);
+
+ return ret;
+}
+
+/**
+ * panthor_vm_map_bo_range() - Map a GEM object range to a VM
+ * @vm: VM to map the GEM to.
+ * @bo: GEM object to map.
+ * @offset: Offset in the GEM object.
+ * @size: Size to map.
+ * @va: Virtual address to map the object to.
+ * @flags: Combination of drm_panthor_vm_bind_op_flags flags.
+ * Only map-related flags are valid.
+ *
+ * Internal use only. For userspace requests, use
+ * panthor_vm_bind_exec_sync_op() instead.
+ *
+ * Return: 0 on success, a negative error code otherwise.
+ */
+int panthor_vm_map_bo_range(struct panthor_vm *vm, struct panthor_gem_object *bo,
+ u64 offset, u64 size, u64 va, u32 flags)
+{
+ struct panthor_vm_op_ctx op_ctx;
+ int ret;
+
+ ret = panthor_vm_prepare_map_op_ctx(&op_ctx, vm, bo, offset, size, va, flags);
+ if (ret)
+ return ret;
+
+ ret = panthor_vm_exec_op(vm, &op_ctx, false);
+ panthor_vm_cleanup_op_ctx(&op_ctx, vm);
+
+ return ret;
+}
+
+/**
+ * panthor_vm_unmap_range() - Unmap a portion of the VA space
+ * @vm: VM to unmap the region from.
+ * @va: Virtual address to unmap. Must be 4k aligned.
+ * @size: Size of the region to unmap. Must be 4k aligned.
+ *
+ * Internal use only. For userspace requests, use
+ * panthor_vm_bind_exec_sync_op() instead.
+ *
+ * Return: 0 on success, a negative error code otherwise.
+ */
+int panthor_vm_unmap_range(struct panthor_vm *vm, u64 va, u64 size)
+{
+ struct panthor_vm_op_ctx op_ctx;
+ int ret;
+
+ ret = panthor_vm_prepare_unmap_op_ctx(&op_ctx, vm, va, size);
+ if (ret)
+ return ret;
+
+ ret = panthor_vm_exec_op(vm, &op_ctx, false);
+ panthor_vm_cleanup_op_ctx(&op_ctx, vm);
+
+ return ret;
+}
+
+/**
+ * panthor_vm_prepare_mapped_bos_resvs() - Prepare resvs on VM BOs.
+ * @exec: Locking/preparation context.
+ * @vm: VM targeted by the GPU job.
+ * @slot_count: Number of slots to reserve.
+ *
+ * GPU jobs assume all BOs bound to the VM at the time the job is submitted
+ * are available when the job is executed. In order to guarantee that, we
+ * need to reserve a slot on all BOs mapped to a VM and update this slot with
+ * the job fence after its submission.
+ *
+ * Return: 0 on success, a negative error code otherwise.
+ */
+int panthor_vm_prepare_mapped_bos_resvs(struct drm_exec *exec, struct panthor_vm *vm,
+ u32 slot_count)
+{
+ int ret;
+
+ /* Acquire the VM lock and reserve a slot for this GPU job. */
+ ret = drm_gpuvm_prepare_vm(&vm->base, exec, slot_count);
+ if (ret)
+ return ret;
+
+ return drm_gpuvm_prepare_objects(&vm->base, exec, slot_count);
+}
+
+/**
+ * panthor_mmu_unplug() - Unplug the MMU logic
+ * @ptdev: Device.
+ *
+ * No access to the MMU regs should be done after this function is called.
+ * We suspend the IRQ and disable all VMs to guarantee that.
+ */
+void panthor_mmu_unplug(struct panthor_device *ptdev)
+{
+ panthor_mmu_irq_suspend(&ptdev->mmu->irq);
+
+ mutex_lock(&ptdev->mmu->as.slots_lock);
+ for (u32 i = 0; i < ARRAY_SIZE(ptdev->mmu->as.slots); i++) {
+ struct panthor_vm *vm = ptdev->mmu->as.slots[i].vm;
+
+ if (vm) {
+ drm_WARN_ON(&ptdev->base, panthor_mmu_as_disable(ptdev, i));
+ panthor_vm_release_as_locked(vm);
+ }
+ }
+ mutex_unlock(&ptdev->mmu->as.slots_lock);
+}
+
+static void panthor_mmu_release_wq(struct drm_device *ddev, void *res)
+{
+ destroy_workqueue(res);
+}
+
+/**
+ * panthor_mmu_init() - Initialize the MMU logic.
+ * @ptdev: Device.
+ *
+ * Return: 0 on success, a negative error code otherwise.
+ */
+int panthor_mmu_init(struct panthor_device *ptdev)
+{
+ u32 va_bits = GPU_MMU_FEATURES_VA_BITS(ptdev->gpu_info.mmu_features);
+ struct panthor_mmu *mmu;
+ int ret, irq;
+
+ mmu = drmm_kzalloc(&ptdev->base, sizeof(*mmu), GFP_KERNEL);
+ if (!mmu)
+ return -ENOMEM;
+
+ INIT_LIST_HEAD(&mmu->as.lru_list);
+
+ ret = drmm_mutex_init(&ptdev->base, &mmu->as.slots_lock);
+ if (ret)
+ return ret;
+
+ INIT_LIST_HEAD(&mmu->vm.list);
+ ret = drmm_mutex_init(&ptdev->base, &mmu->vm.lock);
+ if (ret)
+ return ret;
+
+ ptdev->mmu = mmu;
+
+ irq = platform_get_irq_byname(to_platform_device(ptdev->base.dev), "mmu");
+ if (irq <= 0)
+ return -ENODEV;
+
+ ret = panthor_request_mmu_irq(ptdev, &mmu->irq, irq,
+ panthor_mmu_fault_mask(ptdev, ~0));
+ if (ret)
+ return ret;
+
+ mmu->vm.wq = alloc_workqueue("panthor-vm-bind", WQ_UNBOUND, 0);
+ if (!mmu->vm.wq)
+ return -ENOMEM;
+
+ /* On 32-bit kernels, the VA space is limited by the io_pgtable_ops abstraction,
+ * which passes iova as an unsigned long. Patch the mmu_features to reflect this
+ * limitation.
+ */
+ if (sizeof(unsigned long) * 8 < va_bits) {
+ ptdev->gpu_info.mmu_features &= ~GENMASK(7, 0);
+ ptdev->gpu_info.mmu_features |= sizeof(unsigned long) * 8;
+ }
+
+ return drmm_add_action_or_reset(&ptdev->base, panthor_mmu_release_wq, mmu->vm.wq);
+}
+
+#ifdef CONFIG_DEBUG_FS
+static int show_vm_gpuvas(struct panthor_vm *vm, struct seq_file *m)
+{
+ int ret;
+
+ mutex_lock(&vm->op_lock);
+ ret = drm_debugfs_gpuva_info(m, &vm->base);
+ mutex_unlock(&vm->op_lock);
+
+ return ret;
+}
+
+static int show_each_vm(struct seq_file *m, void *arg)
+{
+ struct drm_info_node *node = (struct drm_info_node *)m->private;
+ struct drm_device *ddev = node->minor->dev;
+ struct panthor_device *ptdev = container_of(ddev, struct panthor_device, base);
+ int (*show)(struct panthor_vm *, struct seq_file *) = node->info_ent->data;
+ struct panthor_vm *vm;
+ int ret = 0;
+
+ mutex_lock(&ptdev->mmu->vm.lock);
+ list_for_each_entry(vm, &ptdev->mmu->vm.list, node) {
+ ret = show(vm, m);
+ if (ret < 0)
+ break;
+
+ seq_puts(m, "\n");
+ }
+ mutex_unlock(&ptdev->mmu->vm.lock);
+
+ return ret;
+}
+
+static struct drm_info_list panthor_mmu_debugfs_list[] = {
+ DRM_DEBUGFS_GPUVA_INFO(show_each_vm, show_vm_gpuvas),
+};
+
+/**
+ * panthor_mmu_debugfs_init() - Initialize MMU debugfs entries
+ * @minor: Minor.
+ */
+void panthor_mmu_debugfs_init(struct drm_minor *minor)
+{
+ drm_debugfs_create_files(panthor_mmu_debugfs_list,
+ ARRAY_SIZE(panthor_mmu_debugfs_list),
+ minor->debugfs_root, minor);
+}
+#endif /* CONFIG_DEBUG_FS */
+
+/**
+ * panthor_mmu_pt_cache_init() - Initialize the page table cache.
+ *
+ * Return: 0 on success, a negative error code otherwise.
+ */
+int panthor_mmu_pt_cache_init(void)
+{
+ pt_cache = kmem_cache_create("panthor-mmu-pt", SZ_4K, SZ_4K, 0, NULL);
+ if (!pt_cache)
+ return -ENOMEM;
+
+ return 0;
+}
+
+/**
+ * panthor_mmu_pt_cache_fini() - Destroy the page table cache.
+ */
+void panthor_mmu_pt_cache_fini(void)
+{
+ kmem_cache_destroy(pt_cache);
+}
new file mode 100644
@@ -0,0 +1,102 @@
+/* SPDX-License-Identifier: GPL-2.0 or MIT */
+/* Copyright 2019 Linaro, Ltd, Rob Herring <robh@kernel.org> */
+/* Copyright 2023 Collabora ltd. */
+
+#ifndef __PANTHOR_MMU_H__
+#define __PANTHOR_MMU_H__
+
+#include <linux/dma-resv.h>
+
+struct drm_exec;
+struct drm_sched_job;
+struct panthor_gem_object;
+struct panthor_heap_pool;
+struct panthor_vm;
+struct panthor_vma;
+struct panthor_mmu;
+
+int panthor_mmu_init(struct panthor_device *ptdev);
+void panthor_mmu_unplug(struct panthor_device *ptdev);
+void panthor_mmu_pre_reset(struct panthor_device *ptdev);
+void panthor_mmu_post_reset(struct panthor_device *ptdev);
+void panthor_mmu_suspend(struct panthor_device *ptdev);
+void panthor_mmu_resume(struct panthor_device *ptdev);
+
+int panthor_vm_map_bo_range(struct panthor_vm *vm, struct panthor_gem_object *bo,
+ u64 offset, u64 size, u64 va, u32 flags);
+int panthor_vm_unmap_range(struct panthor_vm *vm, u64 va, u64 size);
+struct panthor_gem_object *
+panthor_vm_get_bo_for_va(struct panthor_vm *vm, u64 va, u64 *bo_offset);
+
+int panthor_vm_active(struct panthor_vm *vm);
+void panthor_vm_idle(struct panthor_vm *vm);
+int panthor_vm_as(struct panthor_vm *vm);
+
+struct panthor_heap_pool *
+panthor_vm_get_heap_pool(struct panthor_vm *vm, bool create);
+
+struct panthor_vm *panthor_vm_get(struct panthor_vm *vm);
+void panthor_vm_put(struct panthor_vm *vm);
+struct panthor_vm *panthor_vm_create(struct panthor_device *ptdev, bool for_mcu,
+ u64 kernel_va_start, u64 kernel_va_size,
+ u64 kernel_auto_va_start,
+ u64 kernel_auto_va_size);
+
+int panthor_vm_prepare_mapped_bos_resvs(struct drm_exec *exec,
+ struct panthor_vm *vm,
+ u32 slot_count);
+int panthor_vm_add_bos_resvs_deps_to_job(struct panthor_vm *vm,
+ struct drm_sched_job *job);
+void panthor_vm_add_job_fence_to_bos_resvs(struct panthor_vm *vm,
+ struct drm_sched_job *job);
+
+struct dma_resv *panthor_vm_resv(struct panthor_vm *vm);
+struct drm_gem_object *panthor_vm_root_gem(struct panthor_vm *vm);
+
+void panthor_vm_pool_destroy(struct panthor_file *pfile);
+int panthor_vm_pool_create(struct panthor_file *pfile);
+int panthor_vm_pool_create_vm(struct panthor_device *ptdev,
+ struct panthor_vm_pool *pool,
+ struct drm_panthor_vm_create *args);
+int panthor_vm_pool_destroy_vm(struct panthor_vm_pool *pool, u32 handle);
+struct panthor_vm *panthor_vm_pool_get_vm(struct panthor_vm_pool *pool, u32 handle);
+
+bool panthor_vm_has_unhandled_faults(struct panthor_vm *vm);
+bool panthor_vm_is_unusable(struct panthor_vm *vm);
+
+/*
+ * PANTHOR_VM_KERNEL_AUTO_VA: Use this magic address when you want the GEM
+ * logic to auto-allocate the virtual address in the reserved kernel VA range.
+ */
+#define PANTHOR_VM_KERNEL_AUTO_VA ~0ull
+
+int panthor_vm_alloc_va(struct panthor_vm *vm, u64 va, u64 size,
+ struct drm_mm_node *va_node);
+void panthor_vm_free_va(struct panthor_vm *vm, struct drm_mm_node *va_node);
+
+int panthor_vm_bind_exec_sync_op(struct drm_file *file,
+ struct panthor_vm *vm,
+ struct drm_panthor_vm_bind_op *op);
+
+struct drm_sched_job *
+panthor_vm_bind_job_create(struct drm_file *file,
+ struct panthor_vm *vm,
+ const struct drm_panthor_vm_bind_op *op);
+void panthor_vm_bind_job_put(struct drm_sched_job *job);
+int panthor_vm_bind_job_prepare_resvs(struct drm_exec *exec,
+ struct drm_sched_job *job);
+void panthor_vm_bind_job_update_resvs(struct drm_exec *exec, struct drm_sched_job *job);
+
+void panthor_vm_update_resvs(struct panthor_vm *vm, struct drm_exec *exec,
+ struct dma_fence *fence,
+ enum dma_resv_usage private_usage,
+ enum dma_resv_usage extobj_usage);
+
+int panthor_mmu_pt_cache_init(void);
+void panthor_mmu_pt_cache_fini(void);
+
+#ifdef CONFIG_DEBUG_FS
+void panthor_mmu_debugfs_init(struct drm_minor *minor);
+#endif
+
+#endif