1 files changed, 267 insertions, 0 deletions
diff --git a/arch/powerpc/platforms/pasemi/iommu.c b/arch/powerpc/platforms/pasemi/iommu.c
new file mode 100644
index 000000000..0a38663d4
--- /dev/null
+++ b/arch/powerpc/platforms/pasemi/iommu.c
@@ -0,0 +1,267 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * Copyright (C) 2005-2008, PA Semi, Inc
+ *
+ * Maintained by: Olof Johansson <olof@lixom.net>
+ */
+
+#undef DEBUG
+
+#include <linux/memblock.h>
+#include <linux/types.h>
+#include <linux/spinlock.h>
+#include <linux/pci.h>
+#include <linux/of.h>
+#include <asm/iommu.h>
+#include <asm/machdep.h>
+#include <asm/firmware.h>
+
+#include "pasemi.h"
+
+#define IOBMAP_PAGE_SHIFT	12
+#define IOBMAP_PAGE_SIZE	(1 << IOBMAP_PAGE_SHIFT)
+#define IOBMAP_PAGE_MASK	(IOBMAP_PAGE_SIZE - 1)
+
+#define IOB_BASE		0xe0000000
+#define IOB_SIZE		0x3000
+/* Configuration registers */
+#define IOBCAP_REG		0x40
+#define IOBCOM_REG		0x100
+/* Enable IOB address translation */
+#define IOBCOM_ATEN		0x00000100
+
+/* Address decode configuration register */
+#define IOB_AD_REG		0x14c
+/* IOBCOM_AD_REG fields */
+#define IOB_AD_VGPRT		0x00000e00
+#define IOB_AD_VGAEN		0x00000100
+/* Direct mapping settings */
+#define IOB_AD_MPSEL_MASK	0x00000030
+#define IOB_AD_MPSEL_B38	0x00000000
+#define IOB_AD_MPSEL_B40	0x00000010
+#define IOB_AD_MPSEL_B42	0x00000020
+/* Translation window size / enable */
+#define IOB_AD_TRNG_MASK	0x00000003
+#define IOB_AD_TRNG_256M	0x00000000
+#define IOB_AD_TRNG_2G		0x00000001
+#define IOB_AD_TRNG_128G	0x00000003
+
+#define IOB_TABLEBASE_REG	0x154
+
+/* Base of the 64 4-byte L1 registers */
+#define IOB_XLT_L1_REGBASE	0x2b00
+
+/* Register to invalidate TLB entries */
+#define IOB_AT_INVAL_TLB_REG	0x2d00
+
+/* The top two bits of the level 1 entry contains valid and type flags */
+#define IOBMAP_L1E_V		0x40000000
+#define IOBMAP_L1E_V_B		0x80000000
+
+/* For big page entries, the bottom two bits contains flags */
+#define IOBMAP_L1E_BIG_CACHED	0x00000002
+#define IOBMAP_L1E_BIG_PRIORITY	0x00000001
+
+/* For regular level 2 entries, top 2 bits contain valid and cache flags */
+#define IOBMAP_L2E_V		0x80000000
+#define IOBMAP_L2E_V_CACHED	0xc0000000
+
+static void __iomem *iob;
+static u32 iob_l1_emptyval;
+static u32 iob_l2_emptyval;
+static u32 *iob_l2_base;
+
+static struct iommu_table iommu_table_iobmap;
+static int iommu_table_iobmap_inited;
+
+static int iobmap_build(struct iommu_table *tbl, long index,
+			 long npages, unsigned long uaddr,
+			 enum dma_data_direction direction,
+			 unsigned long attrs)
+{
+	u32 *ip;
+	u32 rpn;
+	unsigned long bus_addr;
+
+	pr_debug("iobmap: build at: %lx, %lx, addr: %lx\n", index, npages, uaddr);
+
+	bus_addr = (tbl->it_offset + index) << IOBMAP_PAGE_SHIFT;
+
+	ip = ((u32 *)tbl->it_base) + index;
+
+	while (npages--) {
+		rpn = __pa(uaddr) >> IOBMAP_PAGE_SHIFT;
+
+		*(ip++) = IOBMAP_L2E_V | rpn;
+		/* invalidate tlb, can be optimized more */
+		out_le32(iob+IOB_AT_INVAL_TLB_REG, bus_addr >> 14);
+
+		uaddr += IOBMAP_PAGE_SIZE;
+		bus_addr += IOBMAP_PAGE_SIZE;
+	}
+	return 0;
+}
+
+
+static void iobmap_free(struct iommu_table *tbl, long index,
+			long npages)
+{
+	u32 *ip;
+	unsigned long bus_addr;
+
+	pr_debug("iobmap: free at: %lx, %lx\n", index, npages);
+
+	bus_addr = (tbl->it_offset + index) << IOBMAP_PAGE_SHIFT;
+
+	ip = ((u32 *)tbl->it_base) + index;
+
+	while (npages--) {
+		*(ip++) = iob_l2_emptyval;
+		/* invalidate tlb, can be optimized more */
+		out_le32(iob+IOB_AT_INVAL_TLB_REG, bus_addr >> 14);
+		bus_addr += IOBMAP_PAGE_SIZE;
+	}
+}
+
+static struct iommu_table_ops iommu_table_iobmap_ops = {
+	.set = iobmap_build,
+	.clear  = iobmap_free
+};
+
+static void iommu_table_iobmap_setup(void)
+{
+	pr_debug(" -> %s\n", __func__);
+	iommu_table_iobmap.it_busno = 0;
+	iommu_table_iobmap.it_offset = 0;
+	iommu_table_iobmap.it_page_shift = IOBMAP_PAGE_SHIFT;
+
+	/* it_size is in number of entries */
+	iommu_table_iobmap.it_size =
+		0x80000000 >> iommu_table_iobmap.it_page_shift;
+
+	/* Initialize the common IOMMU code */
+	iommu_table_iobmap.it_base = (unsigned long)iob_l2_base;
+	iommu_table_iobmap.it_index = 0;
+	/* XXXOJN tune this to avoid IOB cache invals.
+	 * Should probably be 8 (64 bytes)
+	 */
+	iommu_table_iobmap.it_blocksize = 4;
+	iommu_table_iobmap.it_ops = &iommu_table_iobmap_ops;
+	if (!iommu_init_table(&iommu_table_iobmap, 0, 0, 0))
+		panic("Failed to initialize iommu table");
+
+	pr_debug(" <- %s\n", __func__);
+}
+
+
+
+static void pci_dma_bus_setup_pasemi(struct pci_bus *bus)
+{
+	pr_debug("pci_dma_bus_setup, bus %p, bus->self %p\n", bus, bus->self);
+
+	if (!iommu_table_iobmap_inited) {
+		iommu_table_iobmap_inited = 1;
+		iommu_table_iobmap_setup();
+	}
+}
+
+
+static void pci_dma_dev_setup_pasemi(struct pci_dev *dev)
+{
+	pr_debug("pci_dma_dev_setup, dev %p (%s)\n", dev, pci_name(dev));
+
+#if !defined(CONFIG_PPC_PASEMI_IOMMU_DMA_FORCE)
+	/* For non-LPAR environment, don't translate anything for the DMA
+	 * engine. The exception to this is if the user has enabled
+	 * CONFIG_PPC_PASEMI_IOMMU_DMA_FORCE at build time.
+	 */
+	if (dev->vendor == 0x1959 && dev->device == 0xa007 &&
+	    !firmware_has_feature(FW_FEATURE_LPAR)) {
+		dev->dev.dma_ops = NULL;
+		/*
+		 * Set the coherent DMA mask to prevent the iommu
+		 * being used unnecessarily
+		 */
+		dev->dev.coherent_dma_mask = DMA_BIT_MASK(44);
+		return;
+	}
+#endif
+
+	set_iommu_table_base(&dev->dev, &iommu_table_iobmap);
+}
+
+static int __init iob_init(struct device_node *dn)
+{
+	unsigned long tmp;
+	u32 regword;
+	int i;
+
+	pr_debug(" -> %s\n", __func__);
+
+	/* For 2G space, 8x64 pages (2^21 bytes) is max total l2 size */
+	iob_l2_base = memblock_alloc_try_nid_raw(1UL << 21, 1UL << 21,
+					MEMBLOCK_LOW_LIMIT, 0x80000000,
+					NUMA_NO_NODE);
+	if (!iob_l2_base)
+		panic("%s: Failed to allocate %lu bytes align=0x%lx max_addr=%x\n",
+		      __func__, 1UL << 21, 1UL << 21, 0x80000000);
+
+	pr_info("IOBMAP L2 allocated at: %p\n", iob_l2_base);
+
+	/* Allocate a spare page to map all invalid IOTLB pages. */
+	tmp = memblock_phys_alloc(IOBMAP_PAGE_SIZE, IOBMAP_PAGE_SIZE);
+	if (!tmp)
+		panic("IOBMAP: Cannot allocate spare page!");
+	/* Empty l1 is marked invalid */
+	iob_l1_emptyval = 0;
+	/* Empty l2 is mapped to dummy page */
+	iob_l2_emptyval = IOBMAP_L2E_V | (tmp >> IOBMAP_PAGE_SHIFT);
+
+	iob = ioremap(IOB_BASE, IOB_SIZE);
+	if (!iob)
+		panic("IOBMAP: Cannot map registers!");
+
+	/* setup direct mapping of the L1 entries */
+	for (i = 0; i < 64; i++) {
+		/* Each L1 covers 32MB, i.e. 8K entries = 32K of ram */
+		regword = IOBMAP_L1E_V | (__pa(iob_l2_base + i*0x2000) >> 12);
+		out_le32(iob+IOB_XLT_L1_REGBASE+i*4, regword);
+	}
+
+	/* set 2GB translation window, based at 0 */
+	regword = in_le32(iob+IOB_AD_REG);
+	regword &= ~IOB_AD_TRNG_MASK;
+	regword |= IOB_AD_TRNG_2G;
+	out_le32(iob+IOB_AD_REG, regword);
+
+	/* Enable translation */
+	regword = in_le32(iob+IOBCOM_REG);
+	regword |= IOBCOM_ATEN;
+	out_le32(iob+IOBCOM_REG, regword);
+
+	pr_debug(" <- %s\n", __func__);
+
+	return 0;
+}
+
+
+/* These are called very early. */
+void __init iommu_init_early_pasemi(void)
+{
+	int iommu_off;
+
+#ifndef CONFIG_PPC_PASEMI_IOMMU
+	iommu_off = 1;
+#else
+	iommu_off = of_chosen &&
+			of_get_property(of_chosen, "linux,iommu-off", NULL);
+#endif
+	if (iommu_off)
+		return;
+
+	iob_init(NULL);
+
+	pasemi_pci_controller_ops.dma_dev_setup = pci_dma_dev_setup_pasemi;
+	pasemi_pci_controller_ops.dma_bus_setup = pci_dma_bus_setup_pasemi;
+	set_pci_dma_ops(&dma_iommu_ops);
+}