diff options
Diffstat (limited to 'drivers/gpu/drm/imagination/pvr_mmu.c')
| -rw-r--r-- | drivers/gpu/drm/imagination/pvr_mmu.c | 2640 |
1 files changed, 2640 insertions, 0 deletions
diff --git a/drivers/gpu/drm/imagination/pvr_mmu.c b/drivers/gpu/drm/imagination/pvr_mmu.c new file mode 100644 index 000000000..4fe70610e --- /dev/null +++ b/drivers/gpu/drm/imagination/pvr_mmu.c @@ -0,0 +1,2640 @@ +// SPDX-License-Identifier: GPL-2.0-only OR MIT +/* Copyright (c) 2023 Imagination Technologies Ltd. */ + +#include "pvr_mmu.h" + +#include "pvr_ccb.h" +#include "pvr_device.h" +#include "pvr_fw.h" +#include "pvr_gem.h" +#include "pvr_power.h" +#include "pvr_rogue_fwif.h" +#include "pvr_rogue_mmu_defs.h" + +#include <drm/drm_drv.h> +#include <linux/atomic.h> +#include <linux/bitops.h> +#include <linux/dma-mapping.h> +#include <linux/kmemleak.h> +#include <linux/minmax.h> +#include <linux/sizes.h> + +#define PVR_SHIFT_FROM_SIZE(size_) (__builtin_ctzll(size_)) +#define PVR_MASK_FROM_SIZE(size_) (~((size_) - U64_C(1))) + +/* + * The value of the device page size (%PVR_DEVICE_PAGE_SIZE) is currently + * pegged to the host page size (%PAGE_SIZE). This chunk of macro goodness both + * ensures that the selected host page size corresponds to a valid device page + * size and sets up values needed by the MMU code below. + */ +#if (PVR_DEVICE_PAGE_SIZE == SZ_4K) +# define ROGUE_MMUCTRL_PAGE_SIZE_X ROGUE_MMUCTRL_PAGE_SIZE_4KB +# define ROGUE_MMUCTRL_PAGE_X_RANGE_SHIFT ROGUE_MMUCTRL_PAGE_4KB_RANGE_SHIFT +# define ROGUE_MMUCTRL_PAGE_X_RANGE_CLRMSK ROGUE_MMUCTRL_PAGE_4KB_RANGE_CLRMSK +#elif (PVR_DEVICE_PAGE_SIZE == SZ_16K) +# define ROGUE_MMUCTRL_PAGE_SIZE_X ROGUE_MMUCTRL_PAGE_SIZE_16KB +# define ROGUE_MMUCTRL_PAGE_X_RANGE_SHIFT ROGUE_MMUCTRL_PAGE_16KB_RANGE_SHIFT +# define ROGUE_MMUCTRL_PAGE_X_RANGE_CLRMSK ROGUE_MMUCTRL_PAGE_16KB_RANGE_CLRMSK +#elif (PVR_DEVICE_PAGE_SIZE == SZ_64K) +# define ROGUE_MMUCTRL_PAGE_SIZE_X ROGUE_MMUCTRL_PAGE_SIZE_64KB +# define ROGUE_MMUCTRL_PAGE_X_RANGE_SHIFT ROGUE_MMUCTRL_PAGE_64KB_RANGE_SHIFT +# define ROGUE_MMUCTRL_PAGE_X_RANGE_CLRMSK ROGUE_MMUCTRL_PAGE_64KB_RANGE_CLRMSK +#elif (PVR_DEVICE_PAGE_SIZE == SZ_256K) +# define ROGUE_MMUCTRL_PAGE_SIZE_X ROGUE_MMUCTRL_PAGE_SIZE_256KB +# define ROGUE_MMUCTRL_PAGE_X_RANGE_SHIFT ROGUE_MMUCTRL_PAGE_256KB_RANGE_SHIFT +# define ROGUE_MMUCTRL_PAGE_X_RANGE_CLRMSK ROGUE_MMUCTRL_PAGE_256KB_RANGE_CLRMSK +#elif (PVR_DEVICE_PAGE_SIZE == SZ_1M) +# define ROGUE_MMUCTRL_PAGE_SIZE_X ROGUE_MMUCTRL_PAGE_SIZE_1MB +# define ROGUE_MMUCTRL_PAGE_X_RANGE_SHIFT ROGUE_MMUCTRL_PAGE_1MB_RANGE_SHIFT +# define ROGUE_MMUCTRL_PAGE_X_RANGE_CLRMSK ROGUE_MMUCTRL_PAGE_1MB_RANGE_CLRMSK +#elif (PVR_DEVICE_PAGE_SIZE == SZ_2M) +# define ROGUE_MMUCTRL_PAGE_SIZE_X ROGUE_MMUCTRL_PAGE_SIZE_2MB +# define ROGUE_MMUCTRL_PAGE_X_RANGE_SHIFT ROGUE_MMUCTRL_PAGE_2MB_RANGE_SHIFT +# define ROGUE_MMUCTRL_PAGE_X_RANGE_CLRMSK ROGUE_MMUCTRL_PAGE_2MB_RANGE_CLRMSK +#else +# error Unsupported device page size PVR_DEVICE_PAGE_SIZE +#endif + +#define ROGUE_MMUCTRL_ENTRIES_PT_VALUE_X \ + (ROGUE_MMUCTRL_ENTRIES_PT_VALUE >> \ + (PVR_DEVICE_PAGE_SHIFT - PVR_SHIFT_FROM_SIZE(SZ_4K))) + +enum pvr_mmu_sync_level { + PVR_MMU_SYNC_LEVEL_NONE = -1, + PVR_MMU_SYNC_LEVEL_0 = 0, + PVR_MMU_SYNC_LEVEL_1 = 1, + PVR_MMU_SYNC_LEVEL_2 = 2, +}; + +#define PVR_MMU_SYNC_LEVEL_0_FLAGS (ROGUE_FWIF_MMUCACHEDATA_FLAGS_PT | \ + ROGUE_FWIF_MMUCACHEDATA_FLAGS_INTERRUPT | \ + ROGUE_FWIF_MMUCACHEDATA_FLAGS_TLB) +#define PVR_MMU_SYNC_LEVEL_1_FLAGS (PVR_MMU_SYNC_LEVEL_0_FLAGS | ROGUE_FWIF_MMUCACHEDATA_FLAGS_PD) +#define PVR_MMU_SYNC_LEVEL_2_FLAGS (PVR_MMU_SYNC_LEVEL_1_FLAGS | ROGUE_FWIF_MMUCACHEDATA_FLAGS_PC) + +/** + * pvr_mmu_set_flush_flags() - Set MMU cache flush flags for next call to + * pvr_mmu_flush_exec(). + * @pvr_dev: Target PowerVR device. + * @flags: MMU flush flags. Must be one of %PVR_MMU_SYNC_LEVEL_*_FLAGS. + * + * This function must be called following any possible change to the MMU page + * tables. + */ +static void pvr_mmu_set_flush_flags(struct pvr_device *pvr_dev, u32 flags) +{ + atomic_fetch_or(flags, &pvr_dev->mmu_flush_cache_flags); +} + +/** + * pvr_mmu_flush_request_all() - Request flush of all MMU caches when + * subsequently calling pvr_mmu_flush_exec(). + * @pvr_dev: Target PowerVR device. + * + * This function must be called following any possible change to the MMU page + * tables. + */ +void pvr_mmu_flush_request_all(struct pvr_device *pvr_dev) +{ + pvr_mmu_set_flush_flags(pvr_dev, PVR_MMU_SYNC_LEVEL_2_FLAGS); +} + +/** + * pvr_mmu_flush_exec() - Execute a flush of all MMU caches previously + * requested. + * @pvr_dev: Target PowerVR device. + * @wait: Do not return until the flush is completed. + * + * This function must be called prior to submitting any new GPU job. The flush + * will complete before the jobs are scheduled, so this can be called once after + * a series of maps. However, a single unmap should always be immediately + * followed by a flush and it should be explicitly waited by setting @wait. + * + * As a failure to flush the MMU caches could risk memory corruption, if the + * flush fails (implying the firmware is not responding) then the GPU device is + * marked as lost. + * + * Returns: + * * 0 on success when @wait is true, or + * * -%EIO if the device is unavailable, or + * * Any error encountered while submitting the flush command via the KCCB. + */ +int pvr_mmu_flush_exec(struct pvr_device *pvr_dev, bool wait) +{ + struct rogue_fwif_kccb_cmd cmd_mmu_cache = {}; + struct rogue_fwif_mmucachedata *cmd_mmu_cache_data = + &cmd_mmu_cache.cmd_data.mmu_cache_data; + int err = 0; + u32 slot; + int idx; + + if (!drm_dev_enter(from_pvr_device(pvr_dev), &idx)) + return -EIO; + + /* Can't flush MMU if the firmware hasn't booted yet. */ + if (!pvr_dev->fw_dev.booted) + goto err_drm_dev_exit; + + cmd_mmu_cache_data->cache_flags = + atomic_xchg(&pvr_dev->mmu_flush_cache_flags, 0); + + if (!cmd_mmu_cache_data->cache_flags) + goto err_drm_dev_exit; + + cmd_mmu_cache.cmd_type = ROGUE_FWIF_KCCB_CMD_MMUCACHE; + + pvr_fw_object_get_fw_addr(pvr_dev->fw_dev.mem.mmucache_sync_obj, + &cmd_mmu_cache_data->mmu_cache_sync_fw_addr); + cmd_mmu_cache_data->mmu_cache_sync_update_value = 0; + + err = pvr_kccb_send_cmd(pvr_dev, &cmd_mmu_cache, &slot); + if (err) + goto err_reset_and_retry; + + err = pvr_kccb_wait_for_completion(pvr_dev, slot, HZ, NULL); + if (err) + goto err_reset_and_retry; + + drm_dev_exit(idx); + + return 0; + +err_reset_and_retry: + /* + * Flush command failure is most likely the result of a firmware lockup. Hard + * reset the GPU and retry. + */ + err = pvr_power_reset(pvr_dev, true); + if (err) + goto err_drm_dev_exit; /* Device is lost. */ + + /* Retry sending flush request. */ + err = pvr_kccb_send_cmd(pvr_dev, &cmd_mmu_cache, &slot); + if (err) { + pvr_device_lost(pvr_dev); + goto err_drm_dev_exit; + } + + if (wait) { + err = pvr_kccb_wait_for_completion(pvr_dev, slot, HZ, NULL); + if (err) + pvr_device_lost(pvr_dev); + } + +err_drm_dev_exit: + drm_dev_exit(idx); + + return err; +} + +/** + * DOC: PowerVR Virtual Memory Handling + */ +/** + * DOC: PowerVR Virtual Memory Handling (constants) + * + * .. c:macro:: PVR_IDX_INVALID + * + * Default value for a u16-based index. + * + * This value cannot be zero, since zero is a valid index value. + */ +#define PVR_IDX_INVALID ((u16)(-1)) + +/** + * DOC: MMU backing pages + */ +/** + * DOC: MMU backing pages (constants) + * + * .. c:macro:: PVR_MMU_BACKING_PAGE_SIZE + * + * Page size of a PowerVR device's integrated MMU. The CPU page size must be + * at least as large as this value for the current implementation; this is + * checked at compile-time. + */ +#define PVR_MMU_BACKING_PAGE_SIZE SZ_4K +static_assert(PAGE_SIZE >= PVR_MMU_BACKING_PAGE_SIZE); + +/** + * struct pvr_mmu_backing_page - Represents a single page used to back a page + * table of any level. + * @dma_addr: DMA address of this page. + * @host_ptr: CPU address of this page. + * @pvr_dev: The PowerVR device to which this page is associated. **For + * internal use only.** + */ +struct pvr_mmu_backing_page { + dma_addr_t dma_addr; + void *host_ptr; +/* private: internal use only */ + struct page *raw_page; + struct pvr_device *pvr_dev; +}; + +/** + * pvr_mmu_backing_page_init() - Initialize a MMU backing page. + * @page: Target backing page. + * @pvr_dev: Target PowerVR device. + * + * This function performs three distinct operations: + * + * 1. Allocate a single page, + * 2. Map the page to the CPU, and + * 3. Map the page to DMA-space. + * + * It is expected that @page be zeroed (e.g. from kzalloc()) before calling + * this function. + * + * Return: + * * 0 on success, or + * * -%ENOMEM if allocation of the backing page or mapping of the backing + * page to DMA fails. + */ +static int +pvr_mmu_backing_page_init(struct pvr_mmu_backing_page *page, + struct pvr_device *pvr_dev) +{ + struct device *dev = from_pvr_device(pvr_dev)->dev; + + struct page *raw_page; + int err; + + dma_addr_t dma_addr; + void *host_ptr; + + raw_page = alloc_page(__GFP_ZERO | GFP_KERNEL); + if (!raw_page) + return -ENOMEM; + + host_ptr = vmap(&raw_page, 1, VM_MAP, pgprot_writecombine(PAGE_KERNEL)); + if (!host_ptr) { + err = -ENOMEM; + goto err_free_page; + } + + dma_addr = dma_map_page(dev, raw_page, 0, PVR_MMU_BACKING_PAGE_SIZE, + DMA_TO_DEVICE); + if (dma_mapping_error(dev, dma_addr)) { + err = -ENOMEM; + goto err_unmap_page; + } + + page->dma_addr = dma_addr; + page->host_ptr = host_ptr; + page->pvr_dev = pvr_dev; + page->raw_page = raw_page; + kmemleak_alloc(page->host_ptr, PAGE_SIZE, 1, GFP_KERNEL); + + return 0; + +err_unmap_page: + vunmap(host_ptr); + +err_free_page: + __free_page(raw_page); + + return err; +} + +/** + * pvr_mmu_backing_page_fini() - Teardown a MMU backing page. + * @page: Target backing page. + * + * This function performs the mirror operations to pvr_mmu_backing_page_init(), + * in reverse order: + * + * 1. Unmap the page from DMA-space, + * 2. Unmap the page from the CPU, and + * 3. Free the page. + * + * It also zeros @page. + * + * It is a no-op to call this function a second (or further) time on any @page. + */ +static void +pvr_mmu_backing_page_fini(struct pvr_mmu_backing_page *page) +{ + struct device *dev; + + /* Do nothing if no allocation is present. */ + if (!page->pvr_dev) + return; + + dev = from_pvr_device(page->pvr_dev)->dev; + + dma_unmap_page(dev, page->dma_addr, PVR_MMU_BACKING_PAGE_SIZE, + DMA_TO_DEVICE); + + kmemleak_free(page->host_ptr); + vunmap(page->host_ptr); + + __free_page(page->raw_page); + + memset(page, 0, sizeof(*page)); +} + +/** + * pvr_mmu_backing_page_sync() - Flush a MMU backing page from the CPU to the + * device. + * @page: Target backing page. + * @flags: MMU flush flags. Must be one of %PVR_MMU_SYNC_LEVEL_*_FLAGS. + * + * .. caution:: + * + * **This is potentially an expensive function call.** Only call + * pvr_mmu_backing_page_sync() once you're sure you have no more changes to + * make to the backing page in the immediate future. + */ +static void +pvr_mmu_backing_page_sync(struct pvr_mmu_backing_page *page, u32 flags) +{ + struct pvr_device *pvr_dev = page->pvr_dev; + struct device *dev; + + /* + * Do nothing if no allocation is present. This may be the case if + * we are unmapping pages. + */ + if (!pvr_dev) + return; + + dev = from_pvr_device(pvr_dev)->dev; + + dma_sync_single_for_device(dev, page->dma_addr, + PVR_MMU_BACKING_PAGE_SIZE, DMA_TO_DEVICE); + + pvr_mmu_set_flush_flags(pvr_dev, flags); +} + +/** + * DOC: Raw page tables + */ + +#define PVR_PAGE_TABLE_TYPEOF_ENTRY(level_) \ + typeof_member(struct pvr_page_table_l##level_##_entry_raw, val) + +#define PVR_PAGE_TABLE_FIELD_GET(level_, name_, field_, entry_) \ + (((entry_).val & \ + ~ROGUE_MMUCTRL_##name_##_DATA_##field_##_CLRMSK) >> \ + ROGUE_MMUCTRL_##name_##_DATA_##field_##_SHIFT) + +#define PVR_PAGE_TABLE_FIELD_PREP(level_, name_, field_, val_) \ + ((((PVR_PAGE_TABLE_TYPEOF_ENTRY(level_))(val_)) \ + << ROGUE_MMUCTRL_##name_##_DATA_##field_##_SHIFT) & \ + ~ROGUE_MMUCTRL_##name_##_DATA_##field_##_CLRMSK) + +/** + * struct pvr_page_table_l2_entry_raw - A single entry in a level 2 page table. + * @val: The raw value of this entry. + * + * This type is a structure for type-checking purposes. At compile-time, its + * size is checked against %ROGUE_MMUCTRL_ENTRY_SIZE_PC_VALUE. + * + * The value stored in this structure can be decoded using the following bitmap: + * + * .. flat-table:: + * :widths: 1 5 + * :stub-columns: 1 + * + * * - 31..4 + * - **Level 1 Page Table Base Address:** Bits 39..12 of the L1 + * page table base address, which is 4KiB aligned. + * + * * - 3..2 + * - *(reserved)* + * + * * - 1 + * - **Pending:** When valid bit is not set, indicates that a valid + * entry is pending and the MMU should wait for the driver to map + * the entry. This is used to support page demand mapping of + * memory. + * + * * - 0 + * - **Valid:** Indicates that the entry contains a valid L1 page + * table. If the valid bit is not set, then an attempted use of + * the page would result in a page fault. + */ +struct pvr_page_table_l2_entry_raw { + u32 val; +} __packed; +static_assert(sizeof(struct pvr_page_table_l2_entry_raw) * 8 == + ROGUE_MMUCTRL_ENTRY_SIZE_PC_VALUE); + +static bool +pvr_page_table_l2_entry_raw_is_valid(struct pvr_page_table_l2_entry_raw entry) +{ + return PVR_PAGE_TABLE_FIELD_GET(2, PC, VALID, entry); +} + +/** + * pvr_page_table_l2_entry_raw_set() - Write a valid entry into a raw level 2 + * page table. + * @entry: Target raw level 2 page table entry. + * @child_table_dma_addr: DMA address of the level 1 page table to be + * associated with @entry. + * + * When calling this function, @child_table_dma_addr must be a valid DMA + * address and a multiple of %ROGUE_MMUCTRL_PC_DATA_PD_BASE_ALIGNSIZE. + */ +static void +pvr_page_table_l2_entry_raw_set(struct pvr_page_table_l2_entry_raw *entry, + dma_addr_t child_table_dma_addr) +{ + child_table_dma_addr >>= ROGUE_MMUCTRL_PC_DATA_PD_BASE_ALIGNSHIFT; + + WRITE_ONCE(entry->val, + PVR_PAGE_TABLE_FIELD_PREP(2, PC, VALID, true) | + PVR_PAGE_TABLE_FIELD_PREP(2, PC, ENTRY_PENDING, false) | + PVR_PAGE_TABLE_FIELD_PREP(2, PC, PD_BASE, child_table_dma_addr)); +} + +static void +pvr_page_table_l2_entry_raw_clear(struct pvr_page_table_l2_entry_raw *entry) +{ + WRITE_ONCE(entry->val, 0); +} + +/** + * struct pvr_page_table_l1_entry_raw - A single entry in a level 1 page table. + * @val: The raw value of this entry. + * + * This type is a structure for type-checking purposes. At compile-time, its + * size is checked against %ROGUE_MMUCTRL_ENTRY_SIZE_PD_VALUE. + * + * The value stored in this structure can be decoded using the following bitmap: + * + * .. flat-table:: + * :widths: 1 5 + * :stub-columns: 1 + * + * * - 63..41 + * - *(reserved)* + * + * * - 40 + * - **Pending:** When valid bit is not set, indicates that a valid entry + * is pending and the MMU should wait for the driver to map the entry. + * This is used to support page demand mapping of memory. + * + * * - 39..5 + * - **Level 0 Page Table Base Address:** The way this value is + * interpreted depends on the page size. Bits not specified in the + * table below (e.g. bits 11..5 for page size 4KiB) should be + * considered reserved. + * + * This table shows the bits used in an L1 page table entry to + * represent the Physical Table Base Address for a given Page Size. + * Since each L1 page table entry covers 2MiB of address space, the + * maximum page size is 2MiB. + * + * .. flat-table:: + * :widths: 1 1 1 1 + * :header-rows: 1 + * :stub-columns: 1 + * + * * - Page size + * - L0 page table base address bits + * - Number of L0 page table entries + * - Size of L0 page table + * + * * - 4KiB + * - 39..12 + * - 512 + * - 4KiB + * + * * - 16KiB + * - 39..10 + * - 128 + * - 1KiB + * + * * - 64KiB + * - 39..8 + * - 32 + * - 256B + * + * * - 256KiB + * - 39..6 + * - 8 + * - 64B + * + * * - 1MiB + * - 39..5 (4 = '0') + * - 2 + * - 16B + * + * * - 2MiB + * - 39..5 (4..3 = '00') + * - 1 + * - 8B + * + * * - 4 + * - *(reserved)* + * + * * - 3..1 + * - **Page Size:** Sets the page size, from 4KiB to 2MiB. + * + * * - 0 + * - **Valid:** Indicates that the entry contains a valid L0 page table. + * If the valid bit is not set, then an attempted use of the page would + * result in a page fault. + */ +struct pvr_page_table_l1_entry_raw { + u64 val; +} __packed; +static_assert(sizeof(struct pvr_page_table_l1_entry_raw) * 8 == + ROGUE_MMUCTRL_ENTRY_SIZE_PD_VALUE); + +static bool +pvr_page_table_l1_entry_raw_is_valid(struct pvr_page_table_l1_entry_raw entry) +{ + return PVR_PAGE_TABLE_FIELD_GET(1, PD, VALID, entry); +} + +/** + * pvr_page_table_l1_entry_raw_set() - Write a valid entry into a raw level 1 + * page table. + * @entry: Target raw level 1 page table entry. + * @child_table_dma_addr: DMA address of the level 0 page table to be + * associated with @entry. + * + * When calling this function, @child_table_dma_addr must be a valid DMA + * address and a multiple of 4 KiB. + */ +static void +pvr_page_table_l1_entry_raw_set(struct pvr_page_table_l1_entry_raw *entry, + dma_addr_t child_table_dma_addr) +{ + WRITE_ONCE(entry->val, + PVR_PAGE_TABLE_FIELD_PREP(1, PD, VALID, true) | + PVR_PAGE_TABLE_FIELD_PREP(1, PD, ENTRY_PENDING, false) | + PVR_PAGE_TABLE_FIELD_PREP(1, PD, PAGE_SIZE, ROGUE_MMUCTRL_PAGE_SIZE_X) | + /* + * The use of a 4K-specific macro here is correct. It is + * a future optimization to allocate sub-host-page-sized + * blocks for individual tables, so the condition that any + * page table address is aligned to the size of the + * largest (a 4KB) table currently holds. + */ + (child_table_dma_addr & ~ROGUE_MMUCTRL_PT_BASE_4KB_RANGE_CLRMSK)); +} + +static void +pvr_page_table_l1_entry_raw_clear(struct pvr_page_table_l1_entry_raw *entry) +{ + WRITE_ONCE(entry->val, 0); +} + +/** + * struct pvr_page_table_l0_entry_raw - A single entry in a level 0 page table. + * @val: The raw value of this entry. + * + * This type is a structure for type-checking purposes. At compile-time, its + * size is checked against %ROGUE_MMUCTRL_ENTRY_SIZE_PT_VALUE. + * + * The value stored in this structure can be decoded using the following bitmap: + * + * .. flat-table:: + * :widths: 1 5 + * :stub-columns: 1 + * + * * - 63 + * - *(reserved)* + * + * * - 62 + * - **PM/FW Protect:** Indicates a protected region which only the + * Parameter Manager (PM) or firmware processor can write to. + * + * * - 61..40 + * - **VP Page (High):** Virtual-physical page used for Parameter Manager + * (PM) memory. This field is only used if the additional level of PB + * virtualization is enabled. The VP Page field is needed by the PM in + * order to correctly reconstitute the free lists after render + * completion. This (High) field holds bits 39..18 of the value; the + * Low field holds bits 17..12. Bits 11..0 are always zero because the + * value is always aligned to the 4KiB page size. + * + * * - 39..12 + * - **Physical Page Address:** The way this value is interpreted depends + * on the page size. Bits not specified in the table below (e.g. bits + * 20..12 for page size 2MiB) should be considered reserved. + * + * This table shows the bits used in an L0 page table entry to represent + * the Physical Page Address for a given page size (as defined in the + * associated L1 page table entry). + * + * .. flat-table:: + * :widths: 1 1 + * :header-rows: 1 + * :stub-columns: 1 + * + * * - Page size + * - Physical address bits + * + * * - 4KiB + * - 39..12 + * + * * - 16KiB + * - 39..14 + * + * * - 64KiB + * - 39..16 + * + * * - 256KiB + * - 39..18 + * + * * - 1MiB + * - 39..20 + * + * * - 2MiB + * - 39..21 + * + * * - 11..6 + * - **VP Page (Low):** Continuation of VP Page (High). + * + * * - 5 + * - **Pending:** When valid bit is not set, indicates that a valid entry + * is pending and the MMU should wait for the driver to map the entry. + * This is used to support page demand mapping of memory. + * + * * - 4 + * - **PM Src:** Set on Parameter Manager (PM) allocated page table + * entries when indicated by the PM. Note that this bit will only be set + * by the PM, not by the device driver. + * + * * - 3 + * - **SLC Bypass Control:** Specifies requests to this page should bypass + * the System Level Cache (SLC), if enabled in SLC configuration. + * + * * - 2 + * - **Cache Coherency:** Indicates that the page is coherent (i.e. it + * does not require a cache flush between operations on the CPU and the + * device). + * + * * - 1 + * - **Read Only:** If set, this bit indicates that the page is read only. + * An attempted write to this page would result in a write-protection + * fault. + * + * * - 0 + * - **Valid:** Indicates that the entry contains a valid page. If the + * valid bit is not set, then an attempted use of the page would result + * in a page fault. + */ +struct pvr_page_table_l0_entry_raw { + u64 val; +} __packed; +static_assert(sizeof(struct pvr_page_table_l0_entry_raw) * 8 == + ROGUE_MMUCTRL_ENTRY_SIZE_PT_VALUE); + +/** + * struct pvr_page_flags_raw - The configurable flags from a single entry in a + * level 0 page table. + * @val: The raw value of these flags. Since these are a strict subset of + * &struct pvr_page_table_l0_entry_raw; use that type for our member here. + * + * The flags stored in this type are: PM/FW Protect; SLC Bypass Control; Cache + * Coherency, and Read Only (bits 62, 3, 2 and 1 respectively). + * + * This type should never be instantiated directly; instead use + * pvr_page_flags_raw_create() to ensure only valid bits of @val are set. + */ +struct pvr_page_flags_raw { + struct pvr_page_table_l0_entry_raw val; +} __packed; +static_assert(sizeof(struct pvr_page_flags_raw) == + sizeof(struct pvr_page_table_l0_entry_raw)); + +static bool +pvr_page_table_l0_entry_raw_is_valid(struct pvr_page_table_l0_entry_raw entry) +{ + return PVR_PAGE_TABLE_FIELD_GET(0, PT, VALID, entry); +} + +/** + * pvr_page_table_l0_entry_raw_set() - Write a valid entry into a raw level 0 + * page table. + * @entry: Target raw level 0 page table entry. + * @dma_addr: DMA address of the physical page to be associated with @entry. + * @flags: Options to be set on @entry. + * + * When calling this function, @child_table_dma_addr must be a valid DMA + * address and a multiple of %PVR_DEVICE_PAGE_SIZE. + * + * The @flags parameter is directly assigned into @entry. It is the callers + * responsibility to ensure that only bits specified in + * &struct pvr_page_flags_raw are set in @flags. + */ +static void +pvr_page_table_l0_entry_raw_set(struct pvr_page_table_l0_entry_raw *entry, + dma_addr_t dma_addr, + struct pvr_page_flags_raw flags) +{ + WRITE_ONCE(entry->val, PVR_PAGE_TABLE_FIELD_PREP(0, PT, VALID, true) | + PVR_PAGE_TABLE_FIELD_PREP(0, PT, ENTRY_PENDING, false) | + (dma_addr & ~ROGUE_MMUCTRL_PAGE_X_RANGE_CLRMSK) | + flags.val.val); +} + +static void +pvr_page_table_l0_entry_raw_clear(struct pvr_page_table_l0_entry_raw *entry) +{ + WRITE_ONCE(entry->val, 0); +} + +/** + * pvr_page_flags_raw_create() - Initialize the flag bits of a raw level 0 page + * table entry. + * @read_only: This page is read-only (see: Read Only). + * @cache_coherent: This page does not require cache flushes (see: Cache + * Coherency). + * @slc_bypass: This page bypasses the device cache (see: SLC Bypass Control). + * @pm_fw_protect: This page is only for use by the firmware or Parameter + * Manager (see PM/FW Protect). + * + * For more details on the use of these four options, see their respective + * entries in the table under &struct pvr_page_table_l0_entry_raw. + * + * Return: + * A new &struct pvr_page_flags_raw instance which can be passed directly to + * pvr_page_table_l0_entry_raw_set() or pvr_page_table_l0_insert(). + */ +static struct pvr_page_flags_raw +pvr_page_flags_raw_create(bool read_only, bool cache_coherent, bool slc_bypass, + bool pm_fw_protect) +{ + struct pvr_page_flags_raw flags; + + flags.val.val = + PVR_PAGE_TABLE_FIELD_PREP(0, PT, READ_ONLY, read_only) | + PVR_PAGE_TABLE_FIELD_PREP(0, PT, CC, cache_coherent) | + PVR_PAGE_TABLE_FIELD_PREP(0, PT, SLC_BYPASS_CTRL, slc_bypass) | + PVR_PAGE_TABLE_FIELD_PREP(0, PT, PM_META_PROTECT, pm_fw_protect); + + return flags; +} + +/** + * struct pvr_page_table_l2_raw - The raw data of a level 2 page table. + * + * This type is a structure for type-checking purposes. At compile-time, its + * size is checked against %PVR_MMU_BACKING_PAGE_SIZE. + */ +struct pvr_page_table_l2_raw { + /** @entries: The raw values of this table. */ + struct pvr_page_table_l2_entry_raw + entries[ROGUE_MMUCTRL_ENTRIES_PC_VALUE]; +} __packed; +static_assert(sizeof(struct pvr_page_table_l2_raw) == PVR_MMU_BACKING_PAGE_SIZE); + +/** + * struct pvr_page_table_l1_raw - The raw data of a level 1 page table. + * + * This type is a structure for type-checking purposes. At compile-time, its + * size is checked against %PVR_MMU_BACKING_PAGE_SIZE. + */ +struct pvr_page_table_l1_raw { + /** @entries: The raw values of this table. */ + struct pvr_page_table_l1_entry_raw + entries[ROGUE_MMUCTRL_ENTRIES_PD_VALUE]; +} __packed; +static_assert(sizeof(struct pvr_page_table_l1_raw) == PVR_MMU_BACKING_PAGE_SIZE); + +/** + * struct pvr_page_table_l0_raw - The raw data of a level 0 page table. + * + * This type is a structure for type-checking purposes. At compile-time, its + * size is checked against %PVR_MMU_BACKING_PAGE_SIZE. + * + * .. caution:: + * + * The size of level 0 page tables is variable depending on the page size + * specified in the associated level 1 page table entry. Since the device + * page size in use is pegged to the host page size, it cannot vary at + * runtime. This structure is therefore only defined to contain the required + * number of entries for the current device page size. **You should never + * read or write beyond the last supported entry.** + */ +struct pvr_page_table_l0_raw { + /** @entries: The raw values of this table. */ + struct pvr_page_table_l0_entry_raw + entries[ROGUE_MMUCTRL_ENTRIES_PT_VALUE_X]; +} __packed; +static_assert(sizeof(struct pvr_page_table_l0_raw) <= PVR_MMU_BACKING_PAGE_SIZE); + +/** + * DOC: Mirror page tables + */ + +/* + * We pre-declare these types because they cross-depend on pointers to each + * other. + */ +struct pvr_page_table_l1; +struct pvr_page_table_l0; + +/** + * struct pvr_page_table_l2 - A wrapped level 2 page table. + * + * To access the raw part of this table, use pvr_page_table_l2_get_raw(). + * Alternatively to access a raw entry directly, use + * pvr_page_table_l2_get_entry_raw(). + * + * A level 2 page table forms the root of the page table tree structure, so + * this type has no &parent or &parent_idx members. + */ +struct pvr_page_table_l2 { + /** + * @entries: The children of this node in the page table tree + * structure. These are also mirror tables. The indexing of this array + * is identical to that of the raw equivalent + * (&pvr_page_table_l1_raw.entries). + */ + struct pvr_page_table_l1 *entries[ROGUE_MMUCTRL_ENTRIES_PC_VALUE]; + + /** + * @backing_page: A handle to the memory which holds the raw + * equivalent of this table. **For internal use only.** + */ + struct pvr_mmu_backing_page backing_page; + + /** + * @entry_count: The current number of valid entries (that we know of) + * in this table. This value is essentially a refcount - the table is + * destroyed when this value is decremented to zero by + * pvr_page_table_l2_remove(). + */ + u16 entry_count; +}; + +/** + * pvr_page_table_l2_init() - Initialize a level 2 page table. + * @table: Target level 2 page table. + * @pvr_dev: Target PowerVR device + * + * It is expected that @table be zeroed (e.g. from kzalloc()) before calling + * this function. + * + * Return: + * * 0 on success, or + * * Any error encountered while intializing &table->backing_page using + * pvr_mmu_backing_page_init(). + */ +static int +pvr_page_table_l2_init(struct pvr_page_table_l2 *table, + struct pvr_device *pvr_dev) +{ + return pvr_mmu_backing_page_init(&table->backing_page, pvr_dev); +} + +/** + * pvr_page_table_l2_fini() - Teardown a level 2 page table. + * @table: Target level 2 page table. + * + * It is an error to attempt to use @table after calling this function. + */ +static void +pvr_page_table_l2_fini(struct pvr_page_table_l2 *table) +{ + pvr_mmu_backing_page_fini(&table->backing_page); +} + +/** + * pvr_page_table_l2_sync() - Flush a level 2 page table from the CPU to the + * device. + * @table: Target level 2 page table. + * + * This is just a thin wrapper around pvr_mmu_backing_page_sync(), so the + * warning there applies here too: **Only call pvr_page_table_l2_sync() once + * you're sure you have no more changes to make to** @table **in the immediate + * future.** + * + * If child level 1 page tables of @table also need to be flushed, this should + * be done first using pvr_page_table_l1_sync() *before* calling this function. + */ +static void +pvr_page_table_l2_sync(struct pvr_page_table_l2 *table) +{ + pvr_mmu_backing_page_sync(&table->backing_page, PVR_MMU_SYNC_LEVEL_2_FLAGS); +} + +/** + * pvr_page_table_l2_get_raw() - Access the raw equivalent of a mirror level 2 + * page table. + * @table: Target level 2 page table. + * + * Essentially returns the CPU address of the raw equivalent of @table, cast to + * a &struct pvr_page_table_l2_raw pointer. + * + * You probably want to call pvr_page_table_l2_get_entry_raw() instead. + * + * Return: + * The raw equivalent of @table. + */ +static struct pvr_page_table_l2_raw * +pvr_page_table_l2_get_raw(struct pvr_page_table_l2 *table) +{ + return table->backing_page.host_ptr; +} + +/** + * pvr_page_table_l2_get_entry_raw() - Access an entry from the raw equivalent + * of a mirror level 2 page table. + * @table: Target level 2 page table. + * @idx: Index of the entry to access. + * + * Technically this function returns a pointer to a slot in a raw level 2 page + * table, since the returned "entry" is not guaranteed to be valid. The caller + * must verify the validity of the entry at the returned address (perhaps using + * pvr_page_table_l2_entry_raw_is_valid()) before reading or overwriting it. + * + * The value of @idx is not checked here; it is the callers responsibility to + * ensure @idx refers to a valid index within @table before dereferencing the + * returned pointer. + * + * Return: + * A pointer to the requested raw level 2 page table entry. + */ +static struct pvr_page_table_l2_entry_raw * +pvr_page_table_l2_get_entry_raw(struct pvr_page_table_l2 *table, u16 idx) +{ + return &pvr_page_table_l2_get_raw(table)->entries[idx]; +} + +/** + * pvr_page_table_l2_entry_is_valid() - Check if a level 2 page table entry is + * marked as valid. + * @table: Target level 2 page table. + * @idx: Index of the entry to check. + * + * The value of @idx is not checked here; it is the callers responsibility to + * ensure @idx refers to a valid index within @table before calling this + * function. + */ +static bool +pvr_page_table_l2_entry_is_valid(struct pvr_page_table_l2 *table, u16 idx) +{ + struct pvr_page_table_l2_entry_raw entry_raw = + *pvr_page_table_l2_get_entry_raw(table, idx); + + return pvr_page_table_l2_entry_raw_is_valid(entry_raw); +} + +/** + * struct pvr_page_table_l1 - A wrapped level 1 page table. + * + * To access the raw part of this table, use pvr_page_table_l1_get_raw(). + * Alternatively to access a raw entry directly, use + * pvr_page_table_l1_get_entry_raw(). + */ +struct pvr_page_table_l1 { + /** + * @entries: The children of this node in the page table tree + * structure. These are also mirror tables. The indexing of this array + * is identical to that of the raw equivalent + * (&pvr_page_table_l0_raw.entries). + */ + struct pvr_page_table_l0 *entries[ROGUE_MMUCTRL_ENTRIES_PD_VALUE]; + + /** + * @backing_page: A handle to the memory which holds the raw + * equivalent of this table. **For internal use only.** + */ + struct pvr_mmu_backing_page backing_page; + + union { + /** + * @parent: The parent of this node in the page table tree structure. + * + * This is also a mirror table. + * + * Only valid when the L1 page table is active. When the L1 page table + * has been removed and queued for destruction, the next_free field + * should be used instead. + */ + struct pvr_page_table_l2 *parent; + + /** + * @next_free: Pointer to the next L1 page table to take/free. + * + * Used to form a linked list of L1 page tables. This is used + * when preallocating tables and when the page table has been + * removed and queued for destruction. + */ + struct pvr_page_table_l1 *next_free; + }; + + /** + * @parent_idx: The index of the entry in the parent table (see + * @parent) which corresponds to this table. + */ + u16 parent_idx; + + /** + * @entry_count: The current number of valid entries (that we know of) + * in this table. This value is essentially a refcount - the table is + * destroyed when this value is decremented to zero by + * pvr_page_table_l1_remove(). + */ + u16 entry_count; +}; + +/** + * pvr_page_table_l1_init() - Initialize a level 1 page table. + * @table: Target level 1 page table. + * @pvr_dev: Target PowerVR device + * + * When this function returns successfully, @table is still not considered + * valid. It must be inserted into the page table tree structure with + * pvr_page_table_l2_insert() before it is ready for use. + * + * It is expected that @table be zeroed (e.g. from kzalloc()) before calling + * this function. + * + * Return: + * * 0 on success, or + * * Any error encountered while intializing &table->backing_page using + * pvr_mmu_backing_page_init(). + */ +static int +pvr_page_table_l1_init(struct pvr_page_table_l1 *table, + struct pvr_device *pvr_dev) +{ + table->parent_idx = PVR_IDX_INVALID; + + return pvr_mmu_backing_page_init(&table->backing_page, pvr_dev); +} + +/** + * pvr_page_table_l1_free() - Teardown a level 1 page table. + * @table: Target level 1 page table. + * + * It is an error to attempt to use @table after calling this function, even + * indirectly. This includes calling pvr_page_table_l2_remove(), which must + * be called *before* pvr_page_table_l1_free(). + */ +static void +pvr_page_table_l1_free(struct pvr_page_table_l1 *table) +{ + pvr_mmu_backing_page_fini(&table->backing_page); + kfree(table); +} + +/** + * pvr_page_table_l1_sync() - Flush a level 1 page table from the CPU to the + * device. + * @table: Target level 1 page table. + * + * This is just a thin wrapper around pvr_mmu_backing_page_sync(), so the + * warning there applies here too: **Only call pvr_page_table_l1_sync() once + * you're sure you have no more changes to make to** @table **in the immediate + * future.** + * + * If child level 0 page tables of @table also need to be flushed, this should + * be done first using pvr_page_table_l0_sync() *before* calling this function. + */ +static void +pvr_page_table_l1_sync(struct pvr_page_table_l1 *table) +{ + pvr_mmu_backing_page_sync(&table->backing_page, PVR_MMU_SYNC_LEVEL_1_FLAGS); +} + +/** + * pvr_page_table_l1_get_raw() - Access the raw equivalent of a mirror level 1 + * page table. + * @table: Target level 1 page table. + * + * Essentially returns the CPU address of the raw equivalent of @table, cast to + * a &struct pvr_page_table_l1_raw pointer. + * + * You probably want to call pvr_page_table_l1_get_entry_raw() instead. + * + * Return: + * The raw equivalent of @table. + */ +static struct pvr_page_table_l1_raw * +pvr_page_table_l1_get_raw(struct pvr_page_table_l1 *table) +{ + return table->backing_page.host_ptr; +} + +/** + * pvr_page_table_l1_get_entry_raw() - Access an entry from the raw equivalent + * of a mirror level 1 page table. + * @table: Target level 1 page table. + * @idx: Index of the entry to access. + * + * Technically this function returns a pointer to a slot in a raw level 1 page + * table, since the returned "entry" is not guaranteed to be valid. The caller + * must verify the validity of the entry at the returned address (perhaps using + * pvr_page_table_l1_entry_raw_is_valid()) before reading or overwriting it. + * + * The value of @idx is not checked here; it is the callers responsibility to + * ensure @idx refers to a valid index within @table before dereferencing the + * returned pointer. + * + * Return: + * A pointer to the requested raw level 1 page table entry. + */ +static struct pvr_page_table_l1_entry_raw * +pvr_page_table_l1_get_entry_raw(struct pvr_page_table_l1 *table, u16 idx) +{ + return &pvr_page_table_l1_get_raw(table)->entries[idx]; +} + +/** + * pvr_page_table_l1_entry_is_valid() - Check if a level 1 page table entry is + * marked as valid. + * @table: Target level 1 page table. + * @idx: Index of the entry to check. + * + * The value of @idx is not checked here; it is the callers responsibility to + * ensure @idx refers to a valid index within @table before calling this + * function. + */ +static bool +pvr_page_table_l1_entry_is_valid(struct pvr_page_table_l1 *table, u16 idx) +{ + struct pvr_page_table_l1_entry_raw entry_raw = + *pvr_page_table_l1_get_entry_raw(table, idx); + + return pvr_page_table_l1_entry_raw_is_valid(entry_raw); +} + +/** + * struct pvr_page_table_l0 - A wrapped level 0 page table. + * + * To access the raw part of this table, use pvr_page_table_l0_get_raw(). + * Alternatively to access a raw entry directly, use + * pvr_page_table_l0_get_entry_raw(). + * + * There is no mirror representation of an individual page, so this type has no + * &entries member. + */ +struct pvr_page_table_l0 { + /** + * @backing_page: A handle to the memory which holds the raw + * equivalent of this table. **For internal use only.** + */ + struct pvr_mmu_backing_page backing_page; + + union { + /** + * @parent: The parent of this node in the page table tree structure. + * + * This is also a mirror table. + * + * Only valid when the L0 page table is active. When the L0 page table + * has been removed and queued for destruction, the next_free field + * should be used instead. + */ + struct pvr_page_table_l1 *parent; + + /** + * @next_free: Pointer to the next L0 page table to take/free. + * + * Used to form a linked list of L0 page tables. This is used + * when preallocating tables and when the page table has been + * removed and queued for destruction. + */ + struct pvr_page_table_l0 *next_free; + }; + + /** + * @parent_idx: The index of the entry in the parent table (see + * @parent) which corresponds to this table. + */ + u16 parent_idx; + + /** + * @entry_count: The current number of valid entries (that we know of) + * in this table. This value is essentially a refcount - the table is + * destroyed when this value is decremented to zero by + * pvr_page_table_l0_remove(). + */ + u16 entry_count; +}; + +/** + * pvr_page_table_l0_init() - Initialize a level 0 page table. + * @table: Target level 0 page table. + * @pvr_dev: Target PowerVR device + * + * When this function returns successfully, @table is still not considered + * valid. It must be inserted into the page table tree structure with + * pvr_page_table_l1_insert() before it is ready for use. + * + * It is expected that @table be zeroed (e.g. from kzalloc()) before calling + * this function. + * + * Return: + * * 0 on success, or + * * Any error encountered while intializing &table->backing_page using + * pvr_mmu_backing_page_init(). + */ +static int +pvr_page_table_l0_init(struct pvr_page_table_l0 *table, + struct pvr_device *pvr_dev) +{ + table->parent_idx = PVR_IDX_INVALID; + + return pvr_mmu_backing_page_init(&table->backing_page, pvr_dev); +} + +/** + * pvr_page_table_l0_free() - Teardown a level 0 page table. + * @table: Target level 0 page table. + * + * It is an error to attempt to use @table after calling this function, even + * indirectly. This includes calling pvr_page_table_l1_remove(), which must + * be called *before* pvr_page_table_l0_free(). + */ +static void +pvr_page_table_l0_free(struct pvr_page_table_l0 *table) +{ + pvr_mmu_backing_page_fini(&table->backing_page); + kfree(table); +} + +/** + * pvr_page_table_l0_sync() - Flush a level 0 page table from the CPU to the + * device. + * @table: Target level 0 page table. + * + * This is just a thin wrapper around pvr_mmu_backing_page_sync(), so the + * warning there applies here too: **Only call pvr_page_table_l0_sync() once + * you're sure you have no more changes to make to** @table **in the immediate + * future.** + * + * If child pages of @table also need to be flushed, this should be done first + * using a DMA sync function (e.g. dma_sync_sg_for_device()) *before* calling + * this function. + */ +static void +pvr_page_table_l0_sync(struct pvr_page_table_l0 *table) +{ + pvr_mmu_backing_page_sync(&table->backing_page, PVR_MMU_SYNC_LEVEL_0_FLAGS); +} + +/** + * pvr_page_table_l0_get_raw() - Access the raw equivalent of a mirror level 0 + * page table. + * @table: Target level 0 page table. + * + * Essentially returns the CPU address of the raw equivalent of @table, cast to + * a &struct pvr_page_table_l0_raw pointer. + * + * You probably want to call pvr_page_table_l0_get_entry_raw() instead. + * + * Return: + * The raw equivalent of @table. + */ +static struct pvr_page_table_l0_raw * +pvr_page_table_l0_get_raw(struct pvr_page_table_l0 *table) +{ + return table->backing_page.host_ptr; +} + +/** + * pvr_page_table_l0_get_entry_raw() - Access an entry from the raw equivalent + * of a mirror level 0 page table. + * @table: Target level 0 page table. + * @idx: Index of the entry to access. + * + * Technically this function returns a pointer to a slot in a raw level 0 page + * table, since the returned "entry" is not guaranteed to be valid. The caller + * must verify the validity of the entry at the returned address (perhaps using + * pvr_page_table_l0_entry_raw_is_valid()) before reading or overwriting it. + * + * The value of @idx is not checked here; it is the callers responsibility to + * ensure @idx refers to a valid index within @table before dereferencing the + * returned pointer. This is espcially important for level 0 page tables, which + * can have a variable number of entries. + * + * Return: + * A pointer to the requested raw level 0 page table entry. + */ +static struct pvr_page_table_l0_entry_raw * +pvr_page_table_l0_get_entry_raw(struct pvr_page_table_l0 *table, u16 idx) +{ + return &pvr_page_table_l0_get_raw(table)->entries[idx]; +} + +/** + * pvr_page_table_l0_entry_is_valid() - Check if a level 0 page table entry is + * marked as valid. + * @table: Target level 0 page table. + * @idx: Index of the entry to check. + * + * The value of @idx is not checked here; it is the callers responsibility to + * ensure @idx refers to a valid index within @table before calling this + * function. + */ +static bool +pvr_page_table_l0_entry_is_valid(struct pvr_page_table_l0 *table, u16 idx) +{ + struct pvr_page_table_l0_entry_raw entry_raw = + *pvr_page_table_l0_get_entry_raw(table, idx); + + return pvr_page_table_l0_entry_raw_is_valid(entry_raw); +} + +/** + * struct pvr_mmu_context - context holding data for operations at page + * catalogue level, intended for use with a VM context. + */ +struct pvr_mmu_context { + /** @pvr_dev: The PVR device associated with the owning VM context. */ + struct pvr_device *pvr_dev; + + /** @page_table_l2: The MMU table root. */ + struct pvr_page_table_l2 page_table_l2; +}; + +/** + * struct pvr_page_table_ptr - A reference to a single physical page as indexed + * by the page table structure. + * + * Intended for embedding in a &struct pvr_mmu_op_context. + */ +struct pvr_page_table_ptr { + /** + * @l1_table: A cached handle to the level 1 page table the + * context is currently traversing. + */ + struct pvr_page_table_l1 *l1_table; + + /** + * @l0_table: A cached handle to the level 0 page table the + * context is currently traversing. + */ + struct pvr_page_table_l0 *l0_table; + + /** + * @l2_idx: Index into the level 2 page table the context is + * currently referencing. + */ + u16 l2_idx; + + /** + * @l1_idx: Index into the level 1 page table the context is + * currently referencing. + */ + u16 l1_idx; + + /** + * @l0_idx: Index into the level 0 page table the context is + * currently referencing. + */ + u16 l0_idx; +}; + +/** + * struct pvr_mmu_op_context - context holding data for individual + * device-virtual mapping operations. Intended for use with a VM bind operation. + */ +struct pvr_mmu_op_context { + /** @mmu_ctx: The MMU context associated with the owning VM context. */ + struct pvr_mmu_context *mmu_ctx; + + /** @map: Data specifically for map operations. */ + struct { + /** + * @sgt: Scatter gather table containing pages pinned for use by + * this context - these are currently pinned when initialising + * the VM bind operation. + */ + struct sg_table *sgt; + + /** @sgt_offset: Start address of the device-virtual mapping. */ + u64 sgt_offset; + + /** + * @l1_prealloc_tables: Preallocated l1 page table objects + * use by this context when creating a page mapping. Linked list + * fully created during initialisation. + */ + struct pvr_page_table_l1 *l1_prealloc_tables; + + /** + * @l0_prealloc_tables: Preallocated l0 page table objects + * use by this context when creating a page mapping. Linked list + * fully created during initialisation. + */ + struct pvr_page_table_l0 *l0_prealloc_tables; + } map; + + /** @unmap: Data specifically for unmap operations. */ + struct { + /** + * @l1_free_tables: Collects page table objects freed by unmap + * ops. Linked list empty at creation. + */ + struct pvr_page_table_l1 *l1_free_tables; + + /** + * @l0_free_tables: Collects page table objects freed by unmap + * ops. Linked list empty at creation. + */ + struct pvr_page_table_l0 *l0_free_tables; + } unmap; + + /** + * @curr_page: A reference to a single physical page as indexed by the + * page table structure. + */ + struct pvr_page_table_ptr curr_page; + + /** + * @sync_level_required: The maximum level of the page table tree + * structure which has (possibly) been modified since it was last + * flushed to the device. + * + * This field should only be set with pvr_mmu_op_context_require_sync() + * or indirectly by pvr_mmu_op_context_sync_partial(). + */ + enum pvr_mmu_sync_level sync_level_required; +}; + +/** + * pvr_page_table_l2_insert() - Insert an entry referring to a level 1 page + * table into a level 2 page table. + * @op_ctx: Target MMU op context pointing at the entry to insert the L1 page + * table into. + * @child_table: Target level 1 page table to be referenced by the new entry. + * + * It is the caller's responsibility to ensure @op_ctx.curr_page points to a + * valid L2 entry. + * + * It is the caller's responsibility to execute any memory barries to ensure + * that the creation of @child_table is ordered before the L2 entry is inserted. + */ +static void +pvr_page_table_l2_insert(struct pvr_mmu_op_context *op_ctx, + struct pvr_page_table_l1 *child_table) +{ + struct pvr_page_table_l2 *l2_table = + &op_ctx->mmu_ctx->page_table_l2; + struct pvr_page_table_l2_entry_raw *entry_raw = + pvr_page_table_l2_get_entry_raw(l2_table, + op_ctx->curr_page.l2_idx); + + pvr_page_table_l2_entry_raw_set(entry_raw, + child_table->backing_page.dma_addr); + + child_table->parent = l2_table; + child_table->parent_idx = op_ctx->curr_page.l2_idx; + l2_table->entries[op_ctx->curr_page.l2_idx] = child_table; + ++l2_table->entry_count; + op_ctx->curr_page.l1_table = child_table; +} + +/** + * pvr_page_table_l2_remove() - Remove a level 1 page table from a level 2 page + * table. + * @op_ctx: Target MMU op context pointing at the L2 entry to remove. + * + * It is the caller's responsibility to ensure @op_ctx.curr_page points to a + * valid L2 entry. + */ +static void +pvr_page_table_l2_remove(struct pvr_mmu_op_context *op_ctx) +{ + struct pvr_page_table_l2 *l2_table = + &op_ctx->mmu_ctx->page_table_l2; + struct pvr_page_table_l2_entry_raw *entry_raw = + pvr_page_table_l2_get_entry_raw(l2_table, + op_ctx->curr_page.l1_table->parent_idx); + + WARN_ON(op_ctx->curr_page.l1_table->parent != l2_table); + + pvr_page_table_l2_entry_raw_clear(entry_raw); + + l2_table->entries[op_ctx->curr_page.l1_table->parent_idx] = NULL; + op_ctx->curr_page.l1_table->parent_idx = PVR_IDX_INVALID; + op_ctx->curr_page.l1_table->next_free = op_ctx->unmap.l1_free_tables; + op_ctx->unmap.l1_free_tables = op_ctx->curr_page.l1_table; + op_ctx->curr_page.l1_table = NULL; + + --l2_table->entry_count; +} + +/** + * pvr_page_table_l1_insert() - Insert an entry referring to a level 0 page + * table into a level 1 page table. + * @op_ctx: Target MMU op context pointing at the entry to insert the L0 page + * table into. + * @child_table: L0 page table to insert. + * + * It is the caller's responsibility to ensure @op_ctx.curr_page points to a + * valid L1 entry. + * + * It is the caller's responsibility to execute any memory barries to ensure + * that the creation of @child_table is ordered before the L1 entry is inserted. + */ +static void +pvr_page_table_l1_insert(struct pvr_mmu_op_context *op_ctx, + struct pvr_page_table_l0 *child_table) +{ + struct pvr_page_table_l1_entry_raw *entry_raw = + pvr_page_table_l1_get_entry_raw(op_ctx->curr_page.l1_table, + op_ctx->curr_page.l1_idx); + + pvr_page_table_l1_entry_raw_set(entry_raw, + child_table->backing_page.dma_addr); + + child_table->parent = op_ctx->curr_page.l1_table; + child_table->parent_idx = op_ctx->curr_page.l1_idx; + op_ctx->curr_page.l1_table->entries[op_ctx->curr_page.l1_idx] = child_table; + ++op_ctx->curr_page.l1_table->entry_count; + op_ctx->curr_page.l0_table = child_table; +} + +/** + * pvr_page_table_l1_remove() - Remove a level 0 page table from a level 1 page + * table. + * @op_ctx: Target MMU op context pointing at the L1 entry to remove. + * + * If this function results in the L1 table becoming empty, it will be removed + * from its parent level 2 page table and destroyed. + * + * It is the caller's responsibility to ensure @op_ctx.curr_page points to a + * valid L1 entry. + */ +static void +pvr_page_table_l1_remove(struct pvr_mmu_op_context *op_ctx) +{ + struct pvr_page_table_l1_entry_raw *entry_raw = + pvr_page_table_l1_get_entry_raw(op_ctx->curr_page.l0_table->parent, + op_ctx->curr_page.l0_table->parent_idx); + + WARN_ON(op_ctx->curr_page.l0_table->parent != + op_ctx->curr_page.l1_table); + + pvr_page_table_l1_entry_raw_clear(entry_raw); + + op_ctx->curr_page.l1_table->entries[op_ctx->curr_page.l0_table->parent_idx] = NULL; + op_ctx->curr_page.l0_table->parent_idx = PVR_IDX_INVALID; + op_ctx->curr_page.l0_table->next_free = op_ctx->unmap.l0_free_tables; + op_ctx->unmap.l0_free_tables = op_ctx->curr_page.l0_table; + op_ctx->curr_page.l0_table = NULL; + + if (--op_ctx->curr_page.l1_table->entry_count == 0) { + /* Clear the parent L2 page table entry. */ + if (op_ctx->curr_page.l1_table->parent_idx != PVR_IDX_INVALID) + pvr_page_table_l2_remove(op_ctx); + } +} + +/** + * pvr_page_table_l0_insert() - Insert an entry referring to a physical page + * into a level 0 page table. + * @op_ctx: Target MMU op context pointing at the L0 entry to insert. + * @dma_addr: Target DMA address to be referenced by the new entry. + * @flags: Page options to be stored in the new entry. + * + * It is the caller's responsibility to ensure @op_ctx.curr_page points to a + * valid L0 entry. + */ +static void +pvr_page_table_l0_insert(struct pvr_mmu_op_context *op_ctx, + dma_addr_t dma_addr, struct pvr_page_flags_raw flags) +{ + struct pvr_page_table_l0_entry_raw *entry_raw = + pvr_page_table_l0_get_entry_raw(op_ctx->curr_page.l0_table, + op_ctx->curr_page.l0_idx); + + pvr_page_table_l0_entry_raw_set(entry_raw, dma_addr, flags); + + /* + * There is no entry to set here - we don't keep a mirror of + * individual pages. + */ + + ++op_ctx->curr_page.l0_table->entry_count; +} + +/** + * pvr_page_table_l0_remove() - Remove a physical page from a level 0 page + * table. + * @op_ctx: Target MMU op context pointing at the L0 entry to remove. + * + * If this function results in the L0 table becoming empty, it will be removed + * from its parent L1 page table and destroyed. + * + * It is the caller's responsibility to ensure @op_ctx.curr_page points to a + * valid L0 entry. + */ +static void +pvr_page_table_l0_remove(struct pvr_mmu_op_context *op_ctx) +{ + struct pvr_page_table_l0_entry_raw *entry_raw = + pvr_page_table_l0_get_entry_raw(op_ctx->curr_page.l0_table, + op_ctx->curr_page.l0_idx); + + pvr_page_table_l0_entry_raw_clear(entry_raw); + + /* + * There is no entry to clear here - we don't keep a mirror of + * individual pages. + */ + + if (--op_ctx->curr_page.l0_table->entry_count == 0) { + /* Clear the parent L1 page table entry. */ + if (op_ctx->curr_page.l0_table->parent_idx != PVR_IDX_INVALID) + pvr_page_table_l1_remove(op_ctx); + } +} + +/** + * DOC: Page table index utilities + */ + +/** + * pvr_page_table_l2_idx() - Calculate the level 2 page table index for a + * device-virtual address. + * @device_addr: Target device-virtual address. + * + * This function does not perform any bounds checking - it is the caller's + * responsibility to ensure that @device_addr is valid before interpreting + * the result. + * + * Return: + * The index into a level 2 page table corresponding to @device_addr. + */ +static u16 +pvr_page_table_l2_idx(u64 device_addr) +{ + return (device_addr & ~ROGUE_MMUCTRL_VADDR_PC_INDEX_CLRMSK) >> + ROGUE_MMUCTRL_VADDR_PC_INDEX_SHIFT; +} + +/** + * pvr_page_table_l1_idx() - Calculate the level 1 page table index for a + * device-virtual address. + * @device_addr: Target device-virtual address. + * + * This function does not perform any bounds checking - it is the caller's + * responsibility to ensure that @device_addr is valid before interpreting + * the result. + * + * Return: + * The index into a level 1 page table corresponding to @device_addr. + */ +static u16 +pvr_page_table_l1_idx(u64 device_addr) +{ + return (device_addr & ~ROGUE_MMUCTRL_VADDR_PD_INDEX_CLRMSK) >> + ROGUE_MMUCTRL_VADDR_PD_INDEX_SHIFT; +} + +/** + * pvr_page_table_l0_idx() - Calculate the level 0 page table index for a + * device-virtual address. + * @device_addr: Target device-virtual address. + * + * This function does not perform any bounds checking - it is the caller's + * responsibility to ensure that @device_addr is valid before interpreting + * the result. + * + * Return: + * The index into a level 0 page table corresponding to @device_addr. + */ +static u16 +pvr_page_table_l0_idx(u64 device_addr) +{ + return (device_addr & ~ROGUE_MMUCTRL_VADDR_PT_INDEX_CLRMSK) >> + ROGUE_MMUCTRL_PAGE_X_RANGE_SHIFT; +} + +/** + * DOC: High-level page table operations + */ + +/** + * pvr_page_table_l1_get_or_insert() - Retrieves (optionally inserting if + * necessary) a level 1 page table from the specified level 2 page table entry. + * @op_ctx: Target MMU op context. + * @should_insert: [IN] Specifies whether new page tables should be inserted + * when empty page table entries are encountered during traversal. + * + * Return: + * * 0 on success, or + * + * If @should_insert is %false: + * * -%ENXIO if a level 1 page table would have been inserted. + * + * If @should_insert is %true: + * * Any error encountered while inserting the level 1 page table. + */ +static int +pvr_page_table_l1_get_or_insert(struct pvr_mmu_op_context *op_ctx, + bool should_insert) +{ + struct pvr_page_table_l2 *l2_table = + &op_ctx->mmu_ctx->page_table_l2; + struct pvr_page_table_l1 *table; + + if (pvr_page_table_l2_entry_is_valid(l2_table, + op_ctx->curr_page.l2_idx)) { + op_ctx->curr_page.l1_table = + l2_table->entries[op_ctx->curr_page.l2_idx]; + return 0; + } + + if (!should_insert) + return -ENXIO; + + /* Take a prealloced table. */ + table = op_ctx->map.l1_prealloc_tables; + if (!table) + return -ENOMEM; + + /* Pop */ + op_ctx->map.l1_prealloc_tables = table->next_free; + table->next_free = NULL; + + /* Ensure new table is fully written out before adding to L2 page table. */ + wmb(); + + pvr_page_table_l2_insert(op_ctx, table); + + return 0; +} + +/** + * pvr_page_table_l0_get_or_insert() - Retrieves (optionally inserting if + * necessary) a level 0 page table from the specified level 1 page table entry. + * @op_ctx: Target MMU op context. + * @should_insert: [IN] Specifies whether new page tables should be inserted + * when empty page table entries are encountered during traversal. + * + * Return: + * * 0 on success, + * + * If @should_insert is %false: + * * -%ENXIO if a level 0 page table would have been inserted. + * + * If @should_insert is %true: + * * Any error encountered while inserting the level 0 page table. + */ +static int +pvr_page_table_l0_get_or_insert(struct pvr_mmu_op_context *op_ctx, + bool should_insert) +{ + struct pvr_page_table_l0 *table; + + if (pvr_page_table_l1_entry_is_valid(op_ctx->curr_page.l1_table, + op_ctx->curr_page.l1_idx)) { + op_ctx->curr_page.l0_table = + op_ctx->curr_page.l1_table->entries[op_ctx->curr_page.l1_idx]; + return 0; + } + + if (!should_insert) + return -ENXIO; + + /* Take a prealloced table. */ + table = op_ctx->map.l0_prealloc_tables; + if (!table) + return -ENOMEM; + + /* Pop */ + op_ctx->map.l0_prealloc_tables = table->next_free; + table->next_free = NULL; + + /* Ensure new table is fully written out before adding to L1 page table. */ + wmb(); + + pvr_page_table_l1_insert(op_ctx, table); + + return 0; +} + +/** + * pvr_mmu_context_create() - Create an MMU context. + * @pvr_dev: PVR device associated with owning VM context. + * + * Returns: + * * Newly created MMU context object on success, or + * * -%ENOMEM if no memory is available, + * * Any error code returned by pvr_page_table_l2_init(). + */ +struct pvr_mmu_context *pvr_mmu_context_create(struct pvr_device *pvr_dev) +{ + struct pvr_mmu_context *ctx = kzalloc(sizeof(*ctx), GFP_KERNEL); + int err; + + if (!ctx) + return ERR_PTR(-ENOMEM); + + err = pvr_page_table_l2_init(&ctx->page_table_l2, pvr_dev); + if (err) + return ERR_PTR(err); + + ctx->pvr_dev = pvr_dev; + + return ctx; +} + +/** + * pvr_mmu_context_destroy() - Destroy an MMU context. + * @ctx: Target MMU context. + */ +void pvr_mmu_context_destroy(struct pvr_mmu_context *ctx) +{ + pvr_page_table_l2_fini(&ctx->page_table_l2); + kfree(ctx); +} + +/** + * pvr_mmu_get_root_table_dma_addr() - Get the DMA address of the root of the + * page table structure behind a VM context. + * @ctx: Target MMU context. + */ +dma_addr_t pvr_mmu_get_root_table_dma_addr(struct pvr_mmu_context *ctx) +{ + return ctx->page_table_l2.backing_page.dma_addr; +} + +/** + * pvr_page_table_l1_alloc() - Allocate a l1 page_table object. + * @ctx: MMU context of owning VM context. + * + * Returns: + * * Newly created page table object on success, or + * * -%ENOMEM if no memory is available, + * * Any error code returned by pvr_page_table_l1_init(). + */ +static struct pvr_page_table_l1 * +pvr_page_table_l1_alloc(struct pvr_mmu_context *ctx) +{ + int err; + + struct pvr_page_table_l1 *table = + kzalloc(sizeof(*table), GFP_KERNEL); + + if (!table) + return ERR_PTR(-ENOMEM); + + err = pvr_page_table_l1_init(table, ctx->pvr_dev); + if (err) { + kfree(table); + return ERR_PTR(err); + } + + return table; +} + +/** + * pvr_page_table_l0_alloc() - Allocate a l0 page_table object. + * @ctx: MMU context of owning VM context. + * + * Returns: + * * Newly created page table object on success, or + * * -%ENOMEM if no memory is available, + * * Any error code returned by pvr_page_table_l0_init(). + */ +static struct pvr_page_table_l0 * +pvr_page_table_l0_alloc(struct pvr_mmu_context *ctx) +{ + int err; + + struct pvr_page_table_l0 *table = + kzalloc(sizeof(*table), GFP_KERNEL); + + if (!table) + return ERR_PTR(-ENOMEM); + + err = pvr_page_table_l0_init(table, ctx->pvr_dev); + if (err) { + kfree(table); + return ERR_PTR(err); + } + + return table; +} + +/** + * pvr_mmu_op_context_require_sync() - Mark an MMU op context as requiring a + * sync operation for the referenced page tables up to a specified level. + * @op_ctx: Target MMU op context. + * @level: Maximum page table level for which a sync is required. + */ +static void +pvr_mmu_op_context_require_sync(struct pvr_mmu_op_context *op_ctx, + enum pvr_mmu_sync_level level) +{ + if (op_ctx->sync_level_required < level) + op_ctx->sync_level_required = level; +} + +/** + * pvr_mmu_op_context_sync_manual() - Trigger a sync of some or all of the + * page tables referenced by a MMU op context. + * @op_ctx: Target MMU op context. + * @level: Maximum page table level to sync. + * + * Do not call this function directly. Instead use + * pvr_mmu_op_context_sync_partial() which is checked against the current + * value of &op_ctx->sync_level_required as set by + * pvr_mmu_op_context_require_sync(). + */ +static void +pvr_mmu_op_context_sync_manual(struct pvr_mmu_op_context *op_ctx, + enum pvr_mmu_sync_level level) +{ + /* + * We sync the page table levels in ascending order (starting from the + * leaf node) to ensure consistency. + */ + + WARN_ON(level < PVR_MMU_SYNC_LEVEL_NONE); + + if (level <= PVR_MMU_SYNC_LEVEL_NONE) + return; + + if (op_ctx->curr_page.l0_table) + pvr_page_table_l0_sync(op_ctx->curr_page.l0_table); + + if (level < PVR_MMU_SYNC_LEVEL_1) + return; + + if (op_ctx->curr_page.l1_table) + pvr_page_table_l1_sync(op_ctx->curr_page.l1_table); + + if (level < PVR_MMU_SYNC_LEVEL_2) + return; + + pvr_page_table_l2_sync(&op_ctx->mmu_ctx->page_table_l2); +} + +/** + * pvr_mmu_op_context_sync_partial() - Trigger a sync of some or all of the + * page tables referenced by a MMU op context. + * @op_ctx: Target MMU op context. + * @level: Requested page table level to sync up to (inclusive). + * + * If @level is greater than the maximum level recorded by @op_ctx as requiring + * a sync operation, only the previously recorded maximum will be used. + * + * Additionally, if @level is greater than or equal to the maximum level + * recorded by @op_ctx as requiring a sync operation, that maximum level will be + * reset as a full sync will be performed. This is equivalent to calling + * pvr_mmu_op_context_sync(). + */ +static void +pvr_mmu_op_context_sync_partial(struct pvr_mmu_op_context *op_ctx, + enum pvr_mmu_sync_level level) +{ + /* + * If the requested sync level is greater than or equal to the + * currently required sync level, we do two things: + * * Don't waste time syncing levels we haven't previously marked as + * requiring a sync, and + * * Reset the required sync level since we are about to sync + * everything that was previously marked as requiring a sync. + */ + if (level >= op_ctx->sync_level_required) { + level = op_ctx->sync_level_required; + op_ctx->sync_level_required = PVR_MMU_SYNC_LEVEL_NONE; + } + + pvr_mmu_op_context_sync_manual(op_ctx, level); +} + +/** + * pvr_mmu_op_context_sync() - Trigger a sync of every page table referenced by + * a MMU op context. + * @op_ctx: Target MMU op context. + * + * The maximum level marked internally as requiring a sync will be reset so + * that subsequent calls to this function will be no-ops unless @op_ctx is + * otherwise updated. + */ +static void +pvr_mmu_op_context_sync(struct pvr_mmu_op_context *op_ctx) +{ + pvr_mmu_op_context_sync_manual(op_ctx, op_ctx->sync_level_required); + + op_ctx->sync_level_required = PVR_MMU_SYNC_LEVEL_NONE; +} + +/** + * pvr_mmu_op_context_load_tables() - Load pointers to tables in each level of + * the page table tree structure needed to reference the physical page + * referenced by a MMU op context. + * @op_ctx: Target MMU op context. + * @should_create: Specifies whether new page tables should be created when + * empty page table entries are encountered during traversal. + * @load_level_required: Maximum page table level to load. + * + * If @should_create is %true, this function may modify the stored required + * sync level of @op_ctx as new page tables are created and inserted into their + * respective parents. + * + * Since there is only one root page table, it is technically incorrect to call + * this function with a value of @load_level_required greater than or equal to + * the root level number. However, this is not explicitly disallowed here. + * + * Return: + * * 0 on success, + * * Any error returned by pvr_page_table_l1_get_or_create() if + * @load_level_required >= 1 except -%ENXIO, or + * * Any error returned by pvr_page_table_l0_get_or_create() if + * @load_level_required >= 0 except -%ENXIO. + */ +static int +pvr_mmu_op_context_load_tables(struct pvr_mmu_op_context *op_ctx, + bool should_create, + enum pvr_mmu_sync_level load_level_required) +{ + const struct pvr_page_table_l1 *l1_head_before = + op_ctx->map.l1_prealloc_tables; + const struct pvr_page_table_l0 *l0_head_before = + op_ctx->map.l0_prealloc_tables; + int err; + + /* Clear tables we're about to fetch in case of error states. */ + if (load_level_required >= PVR_MMU_SYNC_LEVEL_1) + op_ctx->curr_page.l1_table = NULL; + + if (load_level_required >= PVR_MMU_SYNC_LEVEL_0) + op_ctx->curr_page.l0_table = NULL; + + /* Get or create L1 page table. */ + if (load_level_required >= PVR_MMU_SYNC_LEVEL_1) { + err = pvr_page_table_l1_get_or_insert(op_ctx, should_create); + if (err) { + /* + * If @should_create is %false and no L1 page table was + * found, return early but without an error. Since + * pvr_page_table_l1_get_or_create() can only return + * -%ENXIO if @should_create is %false, there is no + * need to check it here. + */ + if (err == -ENXIO) + err = 0; + + return err; + } + } + + /* Get or create L0 page table. */ + if (load_level_required >= PVR_MMU_SYNC_LEVEL_0) { + err = pvr_page_table_l0_get_or_insert(op_ctx, should_create); + if (err) { + /* + * If @should_create is %false and no L0 page table was + * found, return early but without an error. Since + * pvr_page_table_l0_get_or_insert() can only return + * -%ENXIO if @should_create is %false, there is no + * need to check it here. + */ + if (err == -ENXIO) + err = 0; + + /* + * At this point, an L1 page table could have been + * inserted but is now empty due to the failed attempt + * at inserting an L0 page table. In this instance, we + * must remove the empty L1 page table ourselves as + * pvr_page_table_l1_remove() is never called as part + * of the error path in + * pvr_page_table_l0_get_or_insert(). + */ + if (l1_head_before != op_ctx->map.l1_prealloc_tables) { + pvr_page_table_l2_remove(op_ctx); + pvr_mmu_op_context_require_sync(op_ctx, PVR_MMU_SYNC_LEVEL_2); + } + + return err; + } + } + + /* + * A sync is only needed if table objects were inserted. This can be + * inferred by checking if the pointer at the head of the linked list + * has changed. + */ + if (l1_head_before != op_ctx->map.l1_prealloc_tables) + pvr_mmu_op_context_require_sync(op_ctx, PVR_MMU_SYNC_LEVEL_2); + else if (l0_head_before != op_ctx->map.l0_prealloc_tables) + pvr_mmu_op_context_require_sync(op_ctx, PVR_MMU_SYNC_LEVEL_1); + + return 0; +} + +/** + * pvr_mmu_op_context_set_curr_page() - Reassign the current page of an MMU op + * context, syncing any page tables previously assigned to it which are no + * longer relevant. + * @op_ctx: Target MMU op context. + * @device_addr: New pointer target. + * @should_create: Specify whether new page tables should be created when + * empty page table entries are encountered during traversal. + * + * This function performs a full sync on the pointer, regardless of which + * levels are modified. + * + * Return: + * * 0 on success, or + * * Any error returned by pvr_mmu_op_context_load_tables(). + */ +static int +pvr_mmu_op_context_set_curr_page(struct pvr_mmu_op_context *op_ctx, + u64 device_addr, bool should_create) +{ + pvr_mmu_op_context_sync(op_ctx); + + op_ctx->curr_page.l2_idx = pvr_page_table_l2_idx(device_addr); + op_ctx->curr_page.l1_idx = pvr_page_table_l1_idx(device_addr); + op_ctx->curr_page.l0_idx = pvr_page_table_l0_idx(device_addr); + op_ctx->curr_page.l1_table = NULL; + op_ctx->curr_page.l0_table = NULL; + + return pvr_mmu_op_context_load_tables(op_ctx, should_create, + PVR_MMU_SYNC_LEVEL_1); +} + +/** + * pvr_mmu_op_context_next_page() - Advance the current page of an MMU op + * context. + * @op_ctx: Target MMU op context. + * @should_create: Specify whether new page tables should be created when + * empty page table entries are encountered during traversal. + * + * If @should_create is %false, it is the caller's responsibility to verify that + * the state of the table references in @op_ctx is valid on return. If -%ENXIO + * is returned, at least one of the table references is invalid. It should be + * noted that @op_ctx as a whole will be left in a valid state if -%ENXIO is + * returned, unlike other error codes. The caller should check which references + * are invalid by comparing them to %NULL. Only &@ptr->l2_table is guaranteed + * to be valid, since it represents the root of the page table tree structure. + * + * Return: + * * 0 on success, + * * -%EPERM if the operation would wrap at the top of the page table + * hierarchy, + * * -%ENXIO if @should_create is %false and a page table of any level would + * have otherwise been created, or + * * Any error returned while attempting to create missing page tables if + * @should_create is %true. + */ +static int +pvr_mmu_op_context_next_page(struct pvr_mmu_op_context *op_ctx, + bool should_create) +{ + s8 load_level_required = PVR_MMU_SYNC_LEVEL_NONE; + + if (++op_ctx->curr_page.l0_idx != ROGUE_MMUCTRL_ENTRIES_PT_VALUE_X) + goto load_tables; + + op_ctx->curr_page.l0_idx = 0; + load_level_required = PVR_MMU_SYNC_LEVEL_0; + + if (++op_ctx->curr_page.l1_idx != ROGUE_MMUCTRL_ENTRIES_PD_VALUE) + goto load_tables; + + op_ctx->curr_page.l1_idx = 0; + load_level_required = PVR_MMU_SYNC_LEVEL_1; + + if (++op_ctx->curr_page.l2_idx != ROGUE_MMUCTRL_ENTRIES_PC_VALUE) + goto load_tables; + + /* + * If the pattern continued, we would set &op_ctx->curr_page.l2_idx to + * zero here. However, that would wrap the top layer of the page table + * hierarchy which is not a valid operation. Instead, we warn and return + * an error. + */ + WARN(true, + "%s(%p) attempted to loop the top of the page table hierarchy", + __func__, op_ctx); + return -EPERM; + + /* If indices have wrapped, we need to load new tables. */ +load_tables: + /* First, flush tables which will be unloaded. */ + pvr_mmu_op_context_sync_partial(op_ctx, load_level_required); + + /* Then load tables from the required level down. */ + return pvr_mmu_op_context_load_tables(op_ctx, should_create, + load_level_required); +} + +/** + * DOC: Single page operations + */ + +/** + * pvr_page_create() - Create a device-virtual memory page and insert it into + * a level 0 page table. + * @op_ctx: Target MMU op context pointing at the device-virtual address of the + * target page. + * @dma_addr: DMA address of the physical page backing the created page. + * @flags: Page options saved on the level 0 page table entry for reading by + * the device. + * + * Return: + * * 0 on success, or + * * -%EEXIST if the requested page already exists. + */ +static int +pvr_page_create(struct pvr_mmu_op_context *op_ctx, dma_addr_t dma_addr, + struct pvr_page_flags_raw flags) +{ + /* Do not create a new page if one already exists. */ + if (pvr_page_table_l0_entry_is_valid(op_ctx->curr_page.l0_table, + op_ctx->curr_page.l0_idx)) { + return -EEXIST; + } + + pvr_page_table_l0_insert(op_ctx, dma_addr, flags); + + pvr_mmu_op_context_require_sync(op_ctx, PVR_MMU_SYNC_LEVEL_0); + + return 0; +} + +/** + * pvr_page_destroy() - Destroy a device page after removing it from its + * parent level 0 page table. + * @op_ctx: Target MMU op context. + */ +static void +pvr_page_destroy(struct pvr_mmu_op_context *op_ctx) +{ + /* Do nothing if the page does not exist. */ + if (!pvr_page_table_l0_entry_is_valid(op_ctx->curr_page.l0_table, + op_ctx->curr_page.l0_idx)) { + return; + } + + /* Clear the parent L0 page table entry. */ + pvr_page_table_l0_remove(op_ctx); + + pvr_mmu_op_context_require_sync(op_ctx, PVR_MMU_SYNC_LEVEL_0); +} + +/** + * pvr_mmu_op_context_destroy() - Destroy an MMU op context. + * @op_ctx: Target MMU op context. + */ +void pvr_mmu_op_context_destroy(struct pvr_mmu_op_context *op_ctx) +{ + const bool flush_caches = + op_ctx->sync_level_required != PVR_MMU_SYNC_LEVEL_NONE; + + pvr_mmu_op_context_sync(op_ctx); + + /* Unmaps should be flushed immediately. Map flushes can be deferred. */ + if (flush_caches && !op_ctx->map.sgt) + pvr_mmu_flush_exec(op_ctx->mmu_ctx->pvr_dev, true); + + while (op_ctx->map.l0_prealloc_tables) { + struct pvr_page_table_l0 *tmp = op_ctx->map.l0_prealloc_tables; + + op_ctx->map.l0_prealloc_tables = + op_ctx->map.l0_prealloc_tables->next_free; + pvr_page_table_l0_free(tmp); + } + + while (op_ctx->map.l1_prealloc_tables) { + struct pvr_page_table_l1 *tmp = op_ctx->map.l1_prealloc_tables; + + op_ctx->map.l1_prealloc_tables = + op_ctx->map.l1_prealloc_tables->next_free; + pvr_page_table_l1_free(tmp); + } + + while (op_ctx->unmap.l0_free_tables) { + struct pvr_page_table_l0 *tmp = op_ctx->unmap.l0_free_tables; + + op_ctx->unmap.l0_free_tables = + op_ctx->unmap.l0_free_tables->next_free; + pvr_page_table_l0_free(tmp); + } + + while (op_ctx->unmap.l1_free_tables) { + struct pvr_page_table_l1 *tmp = op_ctx->unmap.l1_free_tables; + + op_ctx->unmap.l1_free_tables = + op_ctx->unmap.l1_free_tables->next_free; + pvr_page_table_l1_free(tmp); + } + + kfree(op_ctx); +} + +/** + * pvr_mmu_op_context_create() - Create an MMU op context. + * @ctx: MMU context associated with owning VM context. + * @sgt: Scatter gather table containing pages pinned for use by this context. + * @sgt_offset: Start offset of the requested device-virtual memory mapping. + * @size: Size in bytes of the requested device-virtual memory mapping. For an + * unmapping, this should be zero so that no page tables are allocated. + * + * Returns: + * * Newly created MMU op context object on success, or + * * -%ENOMEM if no memory is available, + * * Any error code returned by pvr_page_table_l2_init(). + */ +struct pvr_mmu_op_context * +pvr_mmu_op_context_create(struct pvr_mmu_context *ctx, struct sg_table *sgt, + u64 sgt_offset, u64 size) +{ + int err; + + struct pvr_mmu_op_context *op_ctx = + kzalloc(sizeof(*op_ctx), GFP_KERNEL); + + if (!op_ctx) + return ERR_PTR(-ENOMEM); + + op_ctx->mmu_ctx = ctx; + op_ctx->map.sgt = sgt; + op_ctx->map.sgt_offset = sgt_offset; + op_ctx->sync_level_required = PVR_MMU_SYNC_LEVEL_NONE; + + if (size) { + /* + * The number of page table objects we need to prealloc is + * indicated by the mapping size, start offset and the sizes + * of the areas mapped per PT or PD. The range calculation is + * identical to that for the index into a table for a device + * address, so we reuse those functions here. + */ + const u32 l1_start_idx = pvr_page_table_l2_idx(sgt_offset); + const u32 l1_end_idx = pvr_page_table_l2_idx(sgt_offset + size); + const u32 l1_count = l1_end_idx - l1_start_idx + 1; + const u32 l0_start_idx = pvr_page_table_l1_idx(sgt_offset); + const u32 l0_end_idx = pvr_page_table_l1_idx(sgt_offset + size); + const u32 l0_count = l0_end_idx - l0_start_idx + 1; + + /* + * Alloc and push page table entries until we have enough of + * each type, ending with linked lists of l0 and l1 entries in + * reverse order. + */ + for (int i = 0; i < l1_count; i++) { + struct pvr_page_table_l1 *l1_tmp = + pvr_page_table_l1_alloc(ctx); + + err = PTR_ERR_OR_ZERO(l1_tmp); + if (err) + goto err_cleanup; + + l1_tmp->next_free = op_ctx->map.l1_prealloc_tables; + op_ctx->map.l1_prealloc_tables = l1_tmp; + } + + for (int i = 0; i < l0_count; i++) { + struct pvr_page_table_l0 *l0_tmp = + pvr_page_table_l0_alloc(ctx); + + err = PTR_ERR_OR_ZERO(l0_tmp); + if (err) + goto err_cleanup; + + l0_tmp->next_free = op_ctx->map.l0_prealloc_tables; + op_ctx->map.l0_prealloc_tables = l0_tmp; + } + } + + return op_ctx; + +err_cleanup: + pvr_mmu_op_context_destroy(op_ctx); + + return ERR_PTR(err); +} + +/** + * pvr_mmu_op_context_unmap_curr_page() - Unmap pages from a memory context + * starting from the current page of an MMU op context. + * @op_ctx: Target MMU op context pointing at the first page to unmap. + * @nr_pages: Number of pages to unmap. + * + * Return: + * * 0 on success, or + * * Any error encountered while advancing @op_ctx.curr_page with + * pvr_mmu_op_context_next_page() (except -%ENXIO). + */ +static int +pvr_mmu_op_context_unmap_curr_page(struct pvr_mmu_op_context *op_ctx, + u64 nr_pages) +{ + int err; + + if (nr_pages == 0) + return 0; + + /* + * Destroy first page outside loop, as it doesn't require a page + * advance beforehand. If the L0 page table reference in + * @op_ctx.curr_page is %NULL, there cannot be a mapped page at + * @op_ctx.curr_page (so skip ahead). + */ + if (op_ctx->curr_page.l0_table) + pvr_page_destroy(op_ctx); + + for (u64 page = 1; page < nr_pages; ++page) { + err = pvr_mmu_op_context_next_page(op_ctx, false); + /* + * If the page table tree structure at @op_ctx.curr_page is + * incomplete, skip ahead. We don't care about unmapping pages + * that cannot exist. + * + * FIXME: This could be made more efficient by jumping ahead + * using pvr_mmu_op_context_set_curr_page(). + */ + if (err == -ENXIO) + continue; + else if (err) + return err; + + pvr_page_destroy(op_ctx); + } + + return 0; +} + +/** + * pvr_mmu_unmap() - Unmap pages from a memory context. + * @op_ctx: Target MMU op context. + * @device_addr: First device-virtual address to unmap. + * @size: Size in bytes to unmap. + * + * The total amount of device-virtual memory unmapped is + * @nr_pages * %PVR_DEVICE_PAGE_SIZE. + * + * Returns: + * * 0 on success, or + * * Any error code returned by pvr_page_table_ptr_init(), or + * * Any error code returned by pvr_page_table_ptr_unmap(). + */ +int pvr_mmu_unmap(struct pvr_mmu_op_context *op_ctx, u64 device_addr, u64 size) +{ + int err = pvr_mmu_op_context_set_curr_page(op_ctx, device_addr, false); + + if (err) + return err; + + return pvr_mmu_op_context_unmap_curr_page(op_ctx, + size >> PVR_DEVICE_PAGE_SHIFT); +} + +/** + * pvr_mmu_map_sgl() - Map part of a scatter-gather table entry to + * device-virtual memory. + * @op_ctx: Target MMU op context pointing to the first page that should be + * mapped. + * @sgl: Target scatter-gather table entry. + * @offset: Offset into @sgl to map from. Must result in a starting address + * from @sgl which is CPU page-aligned. + * @size: Size of the memory to be mapped in bytes. Must be a non-zero multiple + * of the device page size. + * @page_flags: Page options to be applied to every device-virtual memory page + * in the created mapping. + * + * Return: + * * 0 on success, + * * -%EINVAL if the range specified by @offset and @size is not completely + * within @sgl, or + * * Any error encountered while creating a page with pvr_page_create(), or + * * Any error encountered while advancing @op_ctx.curr_page with + * pvr_mmu_op_context_next_page(). + */ +static int +pvr_mmu_map_sgl(struct pvr_mmu_op_context *op_ctx, struct scatterlist *sgl, + u64 offset, u64 size, struct pvr_page_flags_raw page_flags) +{ + const unsigned int pages = size >> PVR_DEVICE_PAGE_SHIFT; + dma_addr_t dma_addr = sg_dma_address(sgl) + offset; + const unsigned int dma_len = sg_dma_len(sgl); + struct pvr_page_table_ptr ptr_copy; + unsigned int page; + int err; + + if (size > dma_len || offset > dma_len - size) + return -EINVAL; + + /* + * Before progressing, save a copy of the start pointer so we can use + * it again if we enter an error state and have to destroy pages. + */ + memcpy(&ptr_copy, &op_ctx->curr_page, sizeof(ptr_copy)); + + /* + * Create first page outside loop, as it doesn't require a page advance + * beforehand. + */ + err = pvr_page_create(op_ctx, dma_addr, page_flags); + if (err) + return err; + + for (page = 1; page < pages; ++page) { + err = pvr_mmu_op_context_next_page(op_ctx, true); + if (err) + goto err_destroy_pages; + + dma_addr += PVR_DEVICE_PAGE_SIZE; + + err = pvr_page_create(op_ctx, dma_addr, page_flags); + if (err) + goto err_destroy_pages; + } + + return 0; + +err_destroy_pages: + memcpy(&op_ctx->curr_page, &ptr_copy, sizeof(op_ctx->curr_page)); + err = pvr_mmu_op_context_unmap_curr_page(op_ctx, page); + + return err; +} + +/** + * pvr_mmu_map() - Map an object's virtual memory to physical memory. + * @op_ctx: Target MMU op context. + * @size: Size of memory to be mapped in bytes. Must be a non-zero multiple + * of the device page size. + * @flags: Flags from pvr_gem_object associated with the mapping. + * @device_addr: Virtual device address to map to. Must be device page-aligned. + * + * Returns: + * * 0 on success, or + * * Any error code returned by pvr_page_table_ptr_init(), or + * * Any error code returned by pvr_mmu_map_sgl(), or + * * Any error code returned by pvr_page_table_ptr_next_page(). + */ +int pvr_mmu_map(struct pvr_mmu_op_context *op_ctx, u64 size, u64 flags, + u64 device_addr) +{ + struct pvr_page_table_ptr ptr_copy; + struct pvr_page_flags_raw flags_raw; + struct scatterlist *sgl; + u64 mapped_size = 0; + unsigned int count; + int err; + + if (!size) + return 0; + + if ((op_ctx->map.sgt_offset | size) & ~PVR_DEVICE_PAGE_MASK) + return -EINVAL; + + err = pvr_mmu_op_context_set_curr_page(op_ctx, device_addr, true); + if (err) + return -EINVAL; + + memcpy(&ptr_copy, &op_ctx->curr_page, sizeof(ptr_copy)); + + flags_raw = pvr_page_flags_raw_create(false, false, + flags & DRM_PVR_BO_BYPASS_DEVICE_CACHE, + flags & DRM_PVR_BO_PM_FW_PROTECT); + + /* Map scatter gather table */ + for_each_sgtable_dma_sg(op_ctx->map.sgt, sgl, count) { + const size_t sgl_len = sg_dma_len(sgl); + u64 sgl_offset, map_sgl_len; + + if (sgl_len <= op_ctx->map.sgt_offset) { + op_ctx->map.sgt_offset -= sgl_len; + continue; + } + + sgl_offset = op_ctx->map.sgt_offset; + map_sgl_len = min_t(u64, sgl_len - sgl_offset, size - mapped_size); + + err = pvr_mmu_map_sgl(op_ctx, sgl, sgl_offset, map_sgl_len, + flags_raw); + if (err) + break; + + /* + * Flag the L0 page table as requiring a flush when the MMU op + * context is destroyed. + */ + pvr_mmu_op_context_require_sync(op_ctx, PVR_MMU_SYNC_LEVEL_0); + + op_ctx->map.sgt_offset = 0; + mapped_size += map_sgl_len; + + if (mapped_size >= size) + break; + + err = pvr_mmu_op_context_next_page(op_ctx, true); + if (err) + break; + } + + if (err && mapped_size) { + memcpy(&op_ctx->curr_page, &ptr_copy, sizeof(op_ctx->curr_page)); + pvr_mmu_op_context_unmap_curr_page(op_ctx, + mapped_size >> PVR_DEVICE_PAGE_SHIFT); + } + + return err; +} |