1 files changed, 312 insertions, 0 deletions
diff --git a/drivers/gpu/drm/gma500/gtt.c b/drivers/gpu/drm/gma500/gtt.c
new file mode 100644
index 0000000000..379bc218aa
--- /dev/null
+++ b/drivers/gpu/drm/gma500/gtt.c
@@ -0,0 +1,312 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * Copyright (c) 2007, Intel Corporation.
+ * All Rights Reserved.
+ *
+ * Authors: Thomas Hellstrom <thomas-at-tungstengraphics.com>
+ *	    Alan Cox <alan@linux.intel.com>
+ */
+
+#include "gem.h" /* TODO: for struct psb_gem_object, see psb_gtt_restore() */
+#include "psb_drv.h"
+
+
+/*
+ *	GTT resource allocator - manage page mappings in GTT space
+ */
+
+int psb_gtt_allocate_resource(struct drm_psb_private *pdev, struct resource *res,
+			      const char *name, resource_size_t size, resource_size_t align,
+			      bool stolen, u32 *offset)
+{
+	struct resource *root = pdev->gtt_mem;
+	resource_size_t start, end;
+	int ret;
+
+	if (stolen) {
+		/* The start of the GTT is backed by stolen pages. */
+		start = root->start;
+		end = root->start + pdev->gtt.stolen_size - 1;
+	} else {
+		/* The rest is backed by system pages. */
+		start = root->start + pdev->gtt.stolen_size;
+		end = root->end;
+	}
+
+	res->name = name;
+	ret = allocate_resource(root, res, size, start, end, align, NULL, NULL);
+	if (ret)
+		return ret;
+	*offset = res->start - root->start;
+
+	return 0;
+}
+
+/**
+ *	psb_gtt_mask_pte	-	generate GTT pte entry
+ *	@pfn: page number to encode
+ *	@type: type of memory in the GTT
+ *
+ *	Set the GTT entry for the appropriate memory type.
+ */
+uint32_t psb_gtt_mask_pte(uint32_t pfn, int type)
+{
+	uint32_t mask = PSB_PTE_VALID;
+
+	/* Ensure we explode rather than put an invalid low mapping of
+	   a high mapping page into the gtt */
+	BUG_ON(pfn & ~(0xFFFFFFFF >> PAGE_SHIFT));
+
+	if (type & PSB_MMU_CACHED_MEMORY)
+		mask |= PSB_PTE_CACHED;
+	if (type & PSB_MMU_RO_MEMORY)
+		mask |= PSB_PTE_RO;
+	if (type & PSB_MMU_WO_MEMORY)
+		mask |= PSB_PTE_WO;
+
+	return (pfn << PAGE_SHIFT) | mask;
+}
+
+static u32 __iomem *psb_gtt_entry(struct drm_psb_private *pdev, const struct resource *res)
+{
+	unsigned long offset = res->start - pdev->gtt_mem->start;
+
+	return pdev->gtt_map + (offset >> PAGE_SHIFT);
+}
+
+/* Acquires GTT mutex internally. */
+void psb_gtt_insert_pages(struct drm_psb_private *pdev, const struct resource *res,
+			  struct page **pages)
+{
+	resource_size_t npages, i;
+	u32 __iomem *gtt_slot;
+	u32 pte;
+
+	mutex_lock(&pdev->gtt_mutex);
+
+	/* Write our page entries into the GTT itself */
+
+	npages = resource_size(res) >> PAGE_SHIFT;
+	gtt_slot = psb_gtt_entry(pdev, res);
+
+	for (i = 0; i < npages; ++i, ++gtt_slot) {
+		pte = psb_gtt_mask_pte(page_to_pfn(pages[i]), PSB_MMU_CACHED_MEMORY);
+		iowrite32(pte, gtt_slot);
+	}
+
+	/* Make sure all the entries are set before we return */
+	ioread32(gtt_slot - 1);
+
+	mutex_unlock(&pdev->gtt_mutex);
+}
+
+/* Acquires GTT mutex internally. */
+void psb_gtt_remove_pages(struct drm_psb_private *pdev, const struct resource *res)
+{
+	resource_size_t npages, i;
+	u32 __iomem *gtt_slot;
+	u32 pte;
+
+	mutex_lock(&pdev->gtt_mutex);
+
+	/* Install scratch page for the resource */
+
+	pte = psb_gtt_mask_pte(page_to_pfn(pdev->scratch_page), PSB_MMU_CACHED_MEMORY);
+
+	npages = resource_size(res) >> PAGE_SHIFT;
+	gtt_slot = psb_gtt_entry(pdev, res);
+
+	for (i = 0; i < npages; ++i, ++gtt_slot)
+		iowrite32(pte, gtt_slot);
+
+	/* Make sure all the entries are set before we return */
+	ioread32(gtt_slot - 1);
+
+	mutex_unlock(&pdev->gtt_mutex);
+}
+
+static int psb_gtt_enable(struct drm_psb_private *dev_priv)
+{
+	struct drm_device *dev = &dev_priv->dev;
+	struct pci_dev *pdev = to_pci_dev(dev->dev);
+	int ret;
+
+	ret = pci_read_config_word(pdev, PSB_GMCH_CTRL, &dev_priv->gmch_ctrl);
+	if (ret)
+		return pcibios_err_to_errno(ret);
+	ret = pci_write_config_word(pdev, PSB_GMCH_CTRL, dev_priv->gmch_ctrl | _PSB_GMCH_ENABLED);
+	if (ret)
+		return pcibios_err_to_errno(ret);
+
+	dev_priv->pge_ctl = PSB_RVDC32(PSB_PGETBL_CTL);
+	PSB_WVDC32(dev_priv->pge_ctl | _PSB_PGETBL_ENABLED, PSB_PGETBL_CTL);
+
+	(void)PSB_RVDC32(PSB_PGETBL_CTL);
+
+	return 0;
+}
+
+static void psb_gtt_disable(struct drm_psb_private *dev_priv)
+{
+	struct drm_device *dev = &dev_priv->dev;
+	struct pci_dev *pdev = to_pci_dev(dev->dev);
+
+	pci_write_config_word(pdev, PSB_GMCH_CTRL, dev_priv->gmch_ctrl);
+	PSB_WVDC32(dev_priv->pge_ctl, PSB_PGETBL_CTL);
+
+	(void)PSB_RVDC32(PSB_PGETBL_CTL);
+}
+
+void psb_gtt_fini(struct drm_device *dev)
+{
+	struct drm_psb_private *dev_priv = to_drm_psb_private(dev);
+
+	iounmap(dev_priv->gtt_map);
+	psb_gtt_disable(dev_priv);
+	mutex_destroy(&dev_priv->gtt_mutex);
+}
+
+/* Clear GTT. Use a scratch page to avoid accidents or scribbles. */
+static void psb_gtt_clear(struct drm_psb_private *pdev)
+{
+	resource_size_t pfn_base;
+	unsigned long i;
+	uint32_t pte;
+
+	pfn_base = page_to_pfn(pdev->scratch_page);
+	pte = psb_gtt_mask_pte(pfn_base, PSB_MMU_CACHED_MEMORY);
+
+	for (i = 0; i < pdev->gtt.gtt_pages; ++i)
+		iowrite32(pte, pdev->gtt_map + i);
+
+	(void)ioread32(pdev->gtt_map + i - 1);
+}
+
+static void psb_gtt_init_ranges(struct drm_psb_private *dev_priv)
+{
+	struct drm_device *dev = &dev_priv->dev;
+	struct pci_dev *pdev = to_pci_dev(dev->dev);
+	struct psb_gtt *pg = &dev_priv->gtt;
+	resource_size_t gtt_phys_start, mmu_gatt_start, gtt_start, gtt_pages,
+			gatt_start, gatt_pages;
+	struct resource *gtt_mem;
+
+	/* The root resource we allocate address space from */
+	gtt_phys_start = dev_priv->pge_ctl & PAGE_MASK;
+
+	/*
+	 * The video MMU has a HW bug when accessing 0x0d0000000. Make
+	 * GATT start at 0x0e0000000. This doesn't actually matter for
+	 * us now, but maybe will if the video acceleration ever gets
+	 * opened up.
+	 */
+	mmu_gatt_start = 0xe0000000;
+
+	gtt_start = pci_resource_start(pdev, PSB_GTT_RESOURCE);
+	gtt_pages = pci_resource_len(pdev, PSB_GTT_RESOURCE) >> PAGE_SHIFT;
+
+	/* CDV doesn't report this. In which case the system has 64 gtt pages */
+	if (!gtt_start || !gtt_pages) {
+		dev_dbg(dev->dev, "GTT PCI BAR not initialized.\n");
+		gtt_pages = 64;
+		gtt_start = dev_priv->pge_ctl;
+	}
+
+	gatt_start = pci_resource_start(pdev, PSB_GATT_RESOURCE);
+	gatt_pages = pci_resource_len(pdev, PSB_GATT_RESOURCE) >> PAGE_SHIFT;
+
+	if (!gatt_pages || !gatt_start) {
+		static struct resource fudge;	/* Preferably peppermint */
+
+		/*
+		 * This can occur on CDV systems. Fudge it in this case. We
+		 * really don't care what imaginary space is being allocated
+		 * at this point.
+		 */
+		dev_dbg(dev->dev, "GATT PCI BAR not initialized.\n");
+		gatt_start = 0x40000000;
+		gatt_pages = (128 * 1024 * 1024) >> PAGE_SHIFT;
+
+		/*
+		 * This is a little confusing but in fact the GTT is providing
+		 * a view from the GPU into memory and not vice versa. As such
+		 * this is really allocating space that is not the same as the
+		 * CPU address space on CDV.
+		 */
+		fudge.start = 0x40000000;
+		fudge.end = 0x40000000 + 128 * 1024 * 1024 - 1;
+		fudge.name = "fudge";
+		fudge.flags = IORESOURCE_MEM;
+
+		gtt_mem = &fudge;
+	} else {
+		gtt_mem = &pdev->resource[PSB_GATT_RESOURCE];
+	}
+
+	pg->gtt_phys_start = gtt_phys_start;
+	pg->mmu_gatt_start = mmu_gatt_start;
+	pg->gtt_start = gtt_start;
+	pg->gtt_pages = gtt_pages;
+	pg->gatt_start = gatt_start;
+	pg->gatt_pages = gatt_pages;
+	dev_priv->gtt_mem = gtt_mem;
+}
+
+int psb_gtt_init(struct drm_device *dev)
+{
+	struct drm_psb_private *dev_priv = to_drm_psb_private(dev);
+	struct psb_gtt *pg = &dev_priv->gtt;
+	int ret;
+
+	mutex_init(&dev_priv->gtt_mutex);
+
+	ret = psb_gtt_enable(dev_priv);
+	if (ret)
+		goto err_mutex_destroy;
+
+	psb_gtt_init_ranges(dev_priv);
+
+	dev_priv->gtt_map = ioremap(pg->gtt_phys_start, pg->gtt_pages << PAGE_SHIFT);
+	if (!dev_priv->gtt_map) {
+		dev_err(dev->dev, "Failure to map gtt.\n");
+		ret = -ENOMEM;
+		goto err_psb_gtt_disable;
+	}
+
+	psb_gtt_clear(dev_priv);
+
+	return 0;
+
+err_psb_gtt_disable:
+	psb_gtt_disable(dev_priv);
+err_mutex_destroy:
+	mutex_destroy(&dev_priv->gtt_mutex);
+	return ret;
+}
+
+int psb_gtt_resume(struct drm_device *dev)
+{
+	struct drm_psb_private *dev_priv = to_drm_psb_private(dev);
+	struct psb_gtt *pg = &dev_priv->gtt;
+	unsigned int old_gtt_pages = pg->gtt_pages;
+	int ret;
+
+	/* Enable the GTT */
+	ret = psb_gtt_enable(dev_priv);
+	if (ret)
+		return ret;
+
+	psb_gtt_init_ranges(dev_priv);
+
+	if (old_gtt_pages != pg->gtt_pages) {
+		dev_err(dev->dev, "GTT resume error.\n");
+		ret = -ENODEV;
+		goto err_psb_gtt_disable;
+	}
+
+	psb_gtt_clear(dev_priv);
+
+err_psb_gtt_disable:
+	psb_gtt_disable(dev_priv);
+	return ret;
+}