arch/powerpc/platforms/pasemi/iommu.c - linux - Git at Google

 // 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 <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;
 	iommu_init_table(&iommu_table_iobmap, 0);
 	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);
 }
	// 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 <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;
	iommu_init_table(&iommu_table_iobmap, 0);
	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);
	}