kernel/arch/powerpc/platforms/pasemi/iommu.c
2024-07-22 17:22:30 +08:00

267 lines
6.8 KiB
C

// 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;
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);
}