1 files changed, 309 insertions, 0 deletions
diff --git a/drivers/misc/habanalabs/common/mmu.c b/drivers/misc/habanalabs/common/mmu.c
new file mode 100644
index 000000000..b5058798a
--- /dev/null
+++ b/drivers/misc/habanalabs/common/mmu.c
@@ -0,0 +1,309 @@
+// SPDX-License-Identifier: GPL-2.0
+
+/*
+ * Copyright 2016-2020 HabanaLabs, Ltd.
+ * All Rights Reserved.
+ */
+
+#include <linux/slab.h>
+
+#include "habanalabs.h"
+
+static bool is_dram_va(struct hl_device *hdev, u64 virt_addr)
+{
+	struct asic_fixed_properties *prop = &hdev->asic_prop;
+
+	return hl_mem_area_inside_range(virt_addr, prop->dmmu.page_size,
+					prop->dmmu.start_addr,
+					prop->dmmu.end_addr);
+}
+
+/**
+ * hl_mmu_init() - initialize the MMU module.
+ * @hdev: habanalabs device structure.
+ *
+ * This function does the following:
+ * - Create a pool of pages for pgt_infos.
+ * - Create a shadow table for pgt
+ *
+ * Return: 0 for success, non-zero for failure.
+ */
+int hl_mmu_init(struct hl_device *hdev)
+{
+	if (hdev->mmu_enable)
+		return hdev->mmu_func.init(hdev);
+
+	return 0;
+}
+
+/**
+ * hl_mmu_fini() - release the MMU module.
+ * @hdev: habanalabs device structure.
+ *
+ * This function does the following:
+ * - Disable MMU in H/W.
+ * - Free the pgt_infos pool.
+ *
+ * All contexts should be freed before calling this function.
+ */
+void hl_mmu_fini(struct hl_device *hdev)
+{
+	if (hdev->mmu_enable)
+		hdev->mmu_func.fini(hdev);
+}
+
+/**
+ * hl_mmu_ctx_init() - initialize a context for using the MMU module.
+ * @ctx: pointer to the context structure to initialize.
+ *
+ * Initialize a mutex to protect the concurrent mapping flow, a hash to hold all
+ * page tables hops related to this context.
+ * Return: 0 on success, non-zero otherwise.
+ */
+int hl_mmu_ctx_init(struct hl_ctx *ctx)
+{
+	struct hl_device *hdev = ctx->hdev;
+
+	if (hdev->mmu_enable)
+		return hdev->mmu_func.ctx_init(ctx);
+
+	return 0;
+}
+
+/*
+ * hl_mmu_ctx_fini - disable a ctx from using the mmu module
+ *
+ * @ctx: pointer to the context structure
+ *
+ * This function does the following:
+ * - Free any pgts which were not freed yet
+ * - Free the mutex
+ * - Free DRAM default page mapping hops
+ */
+void hl_mmu_ctx_fini(struct hl_ctx *ctx)
+{
+	struct hl_device *hdev = ctx->hdev;
+
+	if (hdev->mmu_enable)
+		hdev->mmu_func.ctx_fini(ctx);
+}
+
+/*
+ * hl_mmu_unmap - unmaps a virtual addr
+ *
+ * @ctx: pointer to the context structure
+ * @virt_addr: virt addr to map from
+ * @page_size: size of the page to unmap
+ * @flush_pte: whether to do a PCI flush
+ *
+ * This function does the following:
+ * - Check that the virt addr is mapped
+ * - Unmap the virt addr and frees pgts if possible
+ * - Returns 0 on success, -EINVAL if the given addr is not mapped
+ *
+ * Because this function changes the page tables in the device and because it
+ * changes the MMU hash, it must be protected by a lock.
+ * However, because it maps only a single page, the lock should be implemented
+ * in a higher level in order to protect the entire mapping of the memory area
+ *
+ * For optimization reasons PCI flush may be requested once after unmapping of
+ * large area.
+ */
+int hl_mmu_unmap(struct hl_ctx *ctx, u64 virt_addr, u32 page_size,
+		bool flush_pte)
+{
+	struct hl_device *hdev = ctx->hdev;
+	struct asic_fixed_properties *prop = &hdev->asic_prop;
+	struct hl_mmu_properties *mmu_prop;
+	u64 real_virt_addr;
+	u32 real_page_size, npages;
+	int i, rc = 0;
+	bool is_dram_addr;
+
+	if (!hdev->mmu_enable)
+		return 0;
+
+	is_dram_addr = is_dram_va(hdev, virt_addr);
+
+	if (is_dram_addr)
+		mmu_prop = &prop->dmmu;
+	else if ((page_size % prop->pmmu_huge.page_size) == 0)
+		mmu_prop = &prop->pmmu_huge;
+	else
+		mmu_prop = &prop->pmmu;
+
+	/*
+	 * The H/W handles mapping of specific page sizes. Hence if the page
+	 * size is bigger, we break it to sub-pages and unmap them separately.
+	 */
+	if ((page_size % mmu_prop->page_size) == 0) {
+		real_page_size = mmu_prop->page_size;
+	} else {
+		dev_err(hdev->dev,
+			"page size of %u is not %uKB aligned, can't unmap\n",
+			page_size, mmu_prop->page_size >> 10);
+
+		return -EFAULT;
+	}
+
+	npages = page_size / real_page_size;
+	real_virt_addr = virt_addr;
+
+	for (i = 0 ; i < npages ; i++) {
+		rc = hdev->mmu_func.unmap(ctx, real_virt_addr, is_dram_addr);
+		if (rc)
+			break;
+
+		real_virt_addr += real_page_size;
+	}
+
+	if (flush_pte)
+		hdev->mmu_func.flush(ctx);
+
+	return rc;
+}
+
+/*
+ * hl_mmu_map - maps a virtual addr to physical addr
+ *
+ * @ctx: pointer to the context structure
+ * @virt_addr: virt addr to map from
+ * @phys_addr: phys addr to map to
+ * @page_size: physical page size
+ * @flush_pte: whether to do a PCI flush
+ *
+ * This function does the following:
+ * - Check that the virt addr is not mapped
+ * - Allocate pgts as necessary in order to map the virt addr to the phys
+ * - Returns 0 on success, -EINVAL if addr is already mapped, or -ENOMEM.
+ *
+ * Because this function changes the page tables in the device and because it
+ * changes the MMU hash, it must be protected by a lock.
+ * However, because it maps only a single page, the lock should be implemented
+ * in a higher level in order to protect the entire mapping of the memory area
+ *
+ * For optimization reasons PCI flush may be requested once after mapping of
+ * large area.
+ */
+int hl_mmu_map(struct hl_ctx *ctx, u64 virt_addr, u64 phys_addr, u32 page_size,
+		bool flush_pte)
+{
+	struct hl_device *hdev = ctx->hdev;
+	struct asic_fixed_properties *prop = &hdev->asic_prop;
+	struct hl_mmu_properties *mmu_prop;
+	u64 real_virt_addr, real_phys_addr;
+	u32 real_page_size, npages;
+	int i, rc, mapped_cnt = 0;
+	bool is_dram_addr;
+
+	if (!hdev->mmu_enable)
+		return 0;
+
+	is_dram_addr = is_dram_va(hdev, virt_addr);
+
+	if (is_dram_addr)
+		mmu_prop = &prop->dmmu;
+	else if ((page_size % prop->pmmu_huge.page_size) == 0)
+		mmu_prop = &prop->pmmu_huge;
+	else
+		mmu_prop = &prop->pmmu;
+
+	/*
+	 * The H/W handles mapping of specific page sizes. Hence if the page
+	 * size is bigger, we break it to sub-pages and map them separately.
+	 */
+	if ((page_size % mmu_prop->page_size) == 0) {
+		real_page_size = mmu_prop->page_size;
+	} else {
+		dev_err(hdev->dev,
+			"page size of %u is not %uKB aligned, can't unmap\n",
+			page_size, mmu_prop->page_size >> 10);
+
+		return -EFAULT;
+	}
+
+	WARN_ONCE((phys_addr & (real_page_size - 1)),
+		"Mapping 0x%llx with page size of 0x%x is erroneous! Address must be divisible by page size",
+		phys_addr, real_page_size);
+
+	npages = page_size / real_page_size;
+	real_virt_addr = virt_addr;
+	real_phys_addr = phys_addr;
+
+	for (i = 0 ; i < npages ; i++) {
+		rc = hdev->mmu_func.map(ctx, real_virt_addr, real_phys_addr,
+				real_page_size, is_dram_addr);
+		if (rc)
+			goto err;
+
+		real_virt_addr += real_page_size;
+		real_phys_addr += real_page_size;
+		mapped_cnt++;
+	}
+
+	if (flush_pte)
+		hdev->mmu_func.flush(ctx);
+
+	return 0;
+
+err:
+	real_virt_addr = virt_addr;
+	for (i = 0 ; i < mapped_cnt ; i++) {
+		if (hdev->mmu_func.unmap(ctx, real_virt_addr, is_dram_addr))
+			dev_warn_ratelimited(hdev->dev,
+				"failed to unmap va: 0x%llx\n", real_virt_addr);
+
+		real_virt_addr += real_page_size;
+	}
+
+	hdev->mmu_func.flush(ctx);
+
+	return rc;
+}
+
+/*
+ * hl_mmu_swap_out - marks all mapping of the given ctx as swapped out
+ *
+ * @ctx: pointer to the context structure
+ *
+ */
+void hl_mmu_swap_out(struct hl_ctx *ctx)
+{
+	struct hl_device *hdev = ctx->hdev;
+
+	if (hdev->mmu_enable)
+		hdev->mmu_func.swap_out(ctx);
+}
+
+/*
+ * hl_mmu_swap_in - marks all mapping of the given ctx as swapped in
+ *
+ * @ctx: pointer to the context structure
+ *
+ */
+void hl_mmu_swap_in(struct hl_ctx *ctx)
+{
+	struct hl_device *hdev = ctx->hdev;
+
+	if (hdev->mmu_enable)
+		hdev->mmu_func.swap_in(ctx);
+}
+
+int hl_mmu_if_set_funcs(struct hl_device *hdev)
+{
+	if (!hdev->mmu_enable)
+		return 0;
+
+	switch (hdev->asic_type) {
+	case ASIC_GOYA:
+	case ASIC_GAUDI:
+		hl_mmu_v1_set_funcs(hdev);
+		break;
+	default:
+		dev_err(hdev->dev, "Unrecognized ASIC type %d\n",
+			hdev->asic_type);
+		return -EOPNOTSUPP;
+	}
+
+	return 0;
+}