blob: d2b20eba5b87270d21ca78ea2b892bbf361c8aff [file] [log] [blame]
/*
* IOMMU implementation for Cell Broadband Processor Architecture
* We just establish a linear mapping at boot by setting all the
* IOPT cache entries in the CPU.
* The mapping functions should be identical to pci_direct_iommu,
* except for the handling of the high order bit that is required
* by the Spider bridge. These should be split into a separate
* file at the point where we get a different bridge chip.
*
* Copyright (C) 2005 IBM Deutschland Entwicklung GmbH,
* Arnd Bergmann <arndb@de.ibm.com>
*
* Based on linear mapping
* Copyright (C) 2003 Benjamin Herrenschmidt (benh@kernel.crashing.org)
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public License
* as published by the Free Software Foundation; either version
* 2 of the License, or (at your option) any later version.
*/
#undef DEBUG
#include <linux/kernel.h>
#include <linux/pci.h>
#include <linux/delay.h>
#include <linux/string.h>
#include <linux/init.h>
#include <linux/bootmem.h>
#include <linux/mm.h>
#include <linux/dma-mapping.h>
#include <linux/kernel.h>
#include <linux/compiler.h>
#include <asm/sections.h>
#include <asm/iommu.h>
#include <asm/io.h>
#include <asm/prom.h>
#include <asm/pci-bridge.h>
#include <asm/machdep.h>
#include <asm/pmac_feature.h>
#include <asm/abs_addr.h>
#include <asm/system.h>
#include <asm/ppc-pci.h>
#include <asm/udbg.h>
#include "iommu.h"
static inline unsigned long
get_iopt_entry(unsigned long real_address, unsigned long ioid,
unsigned long prot)
{
return (prot & IOPT_PROT_MASK)
| (IOPT_COHERENT)
| (IOPT_ORDER_VC)
| (real_address & IOPT_RPN_MASK)
| (ioid & IOPT_IOID_MASK);
}
typedef struct {
unsigned long val;
} ioste;
static inline ioste
mk_ioste(unsigned long val)
{
ioste ioste = { .val = val, };
return ioste;
}
static inline ioste
get_iost_entry(unsigned long iopt_base, unsigned long io_address, unsigned page_size)
{
unsigned long ps;
unsigned long iostep;
unsigned long nnpt;
unsigned long shift;
switch (page_size) {
case 0x1000000:
ps = IOST_PS_16M;
nnpt = 0; /* one page per segment */
shift = 5; /* segment has 16 iopt entries */
break;
case 0x100000:
ps = IOST_PS_1M;
nnpt = 0; /* one page per segment */
shift = 1; /* segment has 256 iopt entries */
break;
case 0x10000:
ps = IOST_PS_64K;
nnpt = 0x07; /* 8 pages per io page table */
shift = 0; /* all entries are used */
break;
case 0x1000:
ps = IOST_PS_4K;
nnpt = 0x7f; /* 128 pages per io page table */
shift = 0; /* all entries are used */
break;
default: /* not a known compile time constant */
{
/* BUILD_BUG_ON() is not usable here */
extern void __get_iost_entry_bad_page_size(void);
__get_iost_entry_bad_page_size();
}
break;
}
iostep = iopt_base +
/* need 8 bytes per iopte */
(((io_address / page_size * 8)
/* align io page tables on 4k page boundaries */
<< shift)
/* nnpt+1 pages go into each iopt */
& ~(nnpt << 12));
nnpt++; /* this seems to work, but the documentation is not clear
about wether we put nnpt or nnpt-1 into the ioste bits.
In theory, this can't work for 4k pages. */
return mk_ioste(IOST_VALID_MASK
| (iostep & IOST_PT_BASE_MASK)
| ((nnpt << 5) & IOST_NNPT_MASK)
| (ps & IOST_PS_MASK));
}
/* compute the address of an io pte */
static inline unsigned long
get_ioptep(ioste iost_entry, unsigned long io_address)
{
unsigned long iopt_base;
unsigned long page_size;
unsigned long page_number;
unsigned long iopt_offset;
iopt_base = iost_entry.val & IOST_PT_BASE_MASK;
page_size = iost_entry.val & IOST_PS_MASK;
/* decode page size to compute page number */
page_number = (io_address & 0x0fffffff) >> (10 + 2 * page_size);
/* page number is an offset into the io page table */
iopt_offset = (page_number << 3) & 0x7fff8ul;
return iopt_base + iopt_offset;
}
/* compute the tag field of the iopt cache entry */
static inline unsigned long
get_ioc_tag(ioste iost_entry, unsigned long io_address)
{
unsigned long iopte = get_ioptep(iost_entry, io_address);
return IOPT_VALID_MASK
| ((iopte & 0x00000000000000ff8ul) >> 3)
| ((iopte & 0x0000003fffffc0000ul) >> 9);
}
/* compute the hashed 6 bit index for the 4-way associative pte cache */
static inline unsigned long
get_ioc_hash(ioste iost_entry, unsigned long io_address)
{
unsigned long iopte = get_ioptep(iost_entry, io_address);
return ((iopte & 0x000000000000001f8ul) >> 3)
^ ((iopte & 0x00000000000020000ul) >> 17)
^ ((iopte & 0x00000000000010000ul) >> 15)
^ ((iopte & 0x00000000000008000ul) >> 13)
^ ((iopte & 0x00000000000004000ul) >> 11)
^ ((iopte & 0x00000000000002000ul) >> 9)
^ ((iopte & 0x00000000000001000ul) >> 7);
}
/* same as above, but pretend that we have a simpler 1-way associative
pte cache with an 8 bit index */
static inline unsigned long
get_ioc_hash_1way(ioste iost_entry, unsigned long io_address)
{
unsigned long iopte = get_ioptep(iost_entry, io_address);
return ((iopte & 0x000000000000001f8ul) >> 3)
^ ((iopte & 0x00000000000020000ul) >> 17)
^ ((iopte & 0x00000000000010000ul) >> 15)
^ ((iopte & 0x00000000000008000ul) >> 13)
^ ((iopte & 0x00000000000004000ul) >> 11)
^ ((iopte & 0x00000000000002000ul) >> 9)
^ ((iopte & 0x00000000000001000ul) >> 7)
^ ((iopte & 0x0000000000000c000ul) >> 8);
}
static inline ioste
get_iost_cache(void __iomem *base, unsigned long index)
{
unsigned long __iomem *p = (base + IOC_ST_CACHE_DIR);
return mk_ioste(in_be64(&p[index]));
}
static inline void
set_iost_cache(void __iomem *base, unsigned long index, ioste ste)
{
unsigned long __iomem *p = (base + IOC_ST_CACHE_DIR);
pr_debug("ioste %02lx was %016lx, store %016lx", index,
get_iost_cache(base, index).val, ste.val);
out_be64(&p[index], ste.val);
pr_debug(" now %016lx\n", get_iost_cache(base, index).val);
}
static inline unsigned long
get_iopt_cache(void __iomem *base, unsigned long index, unsigned long *tag)
{
unsigned long __iomem *tags = (void *)(base + IOC_PT_CACHE_DIR);
unsigned long __iomem *p = (void *)(base + IOC_PT_CACHE_REG);
*tag = tags[index];
rmb();
return *p;
}
static inline void
set_iopt_cache(void __iomem *base, unsigned long index,
unsigned long tag, unsigned long val)
{
unsigned long __iomem *tags = base + IOC_PT_CACHE_DIR;
unsigned long __iomem *p = base + IOC_PT_CACHE_REG;
out_be64(p, val);
out_be64(&tags[index], tag);
}
static inline void
set_iost_origin(void __iomem *base)
{
unsigned long __iomem *p = base + IOC_ST_ORIGIN;
unsigned long origin = IOSTO_ENABLE | IOSTO_SW;
pr_debug("iost_origin %016lx, now %016lx\n", in_be64(p), origin);
out_be64(p, origin);
}
static inline void
set_iocmd_config(void __iomem *base)
{
unsigned long __iomem *p = base + 0xc00;
unsigned long conf;
conf = in_be64(p);
pr_debug("iost_conf %016lx, now %016lx\n", conf, conf | IOCMD_CONF_TE);
out_be64(p, conf | IOCMD_CONF_TE);
}
static void enable_mapping(void __iomem *base, void __iomem *mmio_base)
{
set_iocmd_config(base);
set_iost_origin(mmio_base);
}
static void iommu_dev_setup_null(struct pci_dev *d) { }
static void iommu_bus_setup_null(struct pci_bus *b) { }
struct cell_iommu {
unsigned long base;
unsigned long mmio_base;
void __iomem *mapped_base;
void __iomem *mapped_mmio_base;
};
static struct cell_iommu cell_iommus[NR_CPUS];
/* initialize the iommu to support a simple linear mapping
* for each DMA window used by any device. For now, we
* happen to know that there is only one DMA window in use,
* starting at iopt_phys_offset. */
static void cell_do_map_iommu(struct cell_iommu *iommu,
unsigned int ioid,
unsigned long map_start,
unsigned long map_size)
{
unsigned long io_address, real_address;
void __iomem *ioc_base, *ioc_mmio_base;
ioste ioste;
unsigned long index;
/* we pretend the io page table was at a very high address */
const unsigned long fake_iopt = 0x10000000000ul;
const unsigned long io_page_size = 0x1000000; /* use 16M pages */
const unsigned long io_segment_size = 0x10000000; /* 256M */
ioc_base = iommu->mapped_base;
ioc_mmio_base = iommu->mapped_mmio_base;
for (real_address = 0, io_address = map_start;
io_address <= map_start + map_size;
real_address += io_page_size, io_address += io_page_size) {
ioste = get_iost_entry(fake_iopt, io_address, io_page_size);
if ((real_address % io_segment_size) == 0) /* segment start */
set_iost_cache(ioc_mmio_base,
io_address >> 28, ioste);
index = get_ioc_hash_1way(ioste, io_address);
pr_debug("addr %08lx, index %02lx, ioste %016lx\n",
io_address, index, ioste.val);
set_iopt_cache(ioc_mmio_base,
get_ioc_hash_1way(ioste, io_address),
get_ioc_tag(ioste, io_address),
get_iopt_entry(real_address, ioid, IOPT_PROT_RW));
}
}
static void iommu_devnode_setup(struct device_node *d)
{
const unsigned int *ioid;
unsigned long map_start, map_size, token;
const unsigned long *dma_window;
struct cell_iommu *iommu;
ioid = get_property(d, "ioid", NULL);
if (!ioid)
pr_debug("No ioid entry found !\n");
dma_window = get_property(d, "ibm,dma-window", NULL);
if (!dma_window)
pr_debug("No ibm,dma-window entry found !\n");
map_start = dma_window[1];
map_size = dma_window[2];
token = dma_window[0] >> 32;
iommu = &cell_iommus[token];
cell_do_map_iommu(iommu, *ioid, map_start, map_size);
}
static void iommu_bus_setup(struct pci_bus *b)
{
struct device_node *d = (struct device_node *)b->sysdata;
iommu_devnode_setup(d);
}
static int cell_map_iommu_hardcoded(int num_nodes)
{
struct cell_iommu *iommu = NULL;
pr_debug("%s(%d): Using hardcoded defaults\n", __FUNCTION__, __LINE__);
/* node 0 */
iommu = &cell_iommus[0];
iommu->mapped_base = ioremap(0x20000511000, 0x1000);
iommu->mapped_mmio_base = ioremap(0x20000510000, 0x1000);
enable_mapping(iommu->mapped_base, iommu->mapped_mmio_base);
cell_do_map_iommu(iommu, 0x048a,
0x20000000ul,0x20000000ul);
if (num_nodes < 2)
return 0;
/* node 1 */
iommu = &cell_iommus[1];
iommu->mapped_base = ioremap(0x30000511000, 0x1000);
iommu->mapped_mmio_base = ioremap(0x30000510000, 0x1000);
enable_mapping(iommu->mapped_base, iommu->mapped_mmio_base);
cell_do_map_iommu(iommu, 0x048a,
0x20000000,0x20000000ul);
return 0;
}
static int cell_map_iommu(void)
{
unsigned int num_nodes = 0;
const unsigned int *node_id;
const unsigned long *base, *mmio_base;
struct device_node *dn;
struct cell_iommu *iommu = NULL;
/* determine number of nodes (=iommus) */
pr_debug("%s(%d): determining number of nodes...", __FUNCTION__, __LINE__);
for(dn = of_find_node_by_type(NULL, "cpu");
dn;
dn = of_find_node_by_type(dn, "cpu")) {
node_id = get_property(dn, "node-id", NULL);
if (num_nodes < *node_id)
num_nodes = *node_id;
}
num_nodes++;
pr_debug("%i found.\n", num_nodes);
/* map the iommu registers for each node */
pr_debug("%s(%d): Looping through nodes\n", __FUNCTION__, __LINE__);
for(dn = of_find_node_by_type(NULL, "cpu");
dn;
dn = of_find_node_by_type(dn, "cpu")) {
node_id = get_property(dn, "node-id", NULL);
base = get_property(dn, "ioc-cache", NULL);
mmio_base = get_property(dn, "ioc-translation", NULL);
if (!base || !mmio_base || !node_id)
return cell_map_iommu_hardcoded(num_nodes);
iommu = &cell_iommus[*node_id];
iommu->base = *base;
iommu->mmio_base = *mmio_base;
iommu->mapped_base = ioremap(*base, 0x1000);
iommu->mapped_mmio_base = ioremap(*mmio_base, 0x1000);
enable_mapping(iommu->mapped_base,
iommu->mapped_mmio_base);
/* everything else will be done in iommu_bus_setup */
}
return 1;
}
static void *cell_alloc_coherent(struct device *hwdev, size_t size,
dma_addr_t *dma_handle, gfp_t flag)
{
void *ret;
ret = (void *)__get_free_pages(flag, get_order(size));
if (ret != NULL) {
memset(ret, 0, size);
*dma_handle = virt_to_abs(ret) | CELL_DMA_VALID;
}
return ret;
}
static void cell_free_coherent(struct device *hwdev, size_t size,
void *vaddr, dma_addr_t dma_handle)
{
free_pages((unsigned long)vaddr, get_order(size));
}
static dma_addr_t cell_map_single(struct device *hwdev, void *ptr,
size_t size, enum dma_data_direction direction)
{
return virt_to_abs(ptr) | CELL_DMA_VALID;
}
static void cell_unmap_single(struct device *hwdev, dma_addr_t dma_addr,
size_t size, enum dma_data_direction direction)
{
}
static int cell_map_sg(struct device *hwdev, struct scatterlist *sg,
int nents, enum dma_data_direction direction)
{
int i;
for (i = 0; i < nents; i++, sg++) {
sg->dma_address = (page_to_phys(sg->page) + sg->offset)
| CELL_DMA_VALID;
sg->dma_length = sg->length;
}
return nents;
}
static void cell_unmap_sg(struct device *hwdev, struct scatterlist *sg,
int nents, enum dma_data_direction direction)
{
}
static int cell_dma_supported(struct device *dev, u64 mask)
{
return mask < 0x100000000ull;
}
static struct dma_mapping_ops cell_iommu_ops = {
.alloc_coherent = cell_alloc_coherent,
.free_coherent = cell_free_coherent,
.map_single = cell_map_single,
.unmap_single = cell_unmap_single,
.map_sg = cell_map_sg,
.unmap_sg = cell_unmap_sg,
.dma_supported = cell_dma_supported,
};
void cell_init_iommu(void)
{
int setup_bus = 0;
if (of_find_node_by_path("/mambo")) {
pr_info("Not using iommu on systemsim\n");
} else {
if (!(of_chosen &&
get_property(of_chosen, "linux,iommu-off", NULL)))
setup_bus = cell_map_iommu();
if (setup_bus) {
pr_debug("%s: IOMMU mapping activated\n", __FUNCTION__);
ppc_md.iommu_dev_setup = iommu_dev_setup_null;
ppc_md.iommu_bus_setup = iommu_bus_setup;
} else {
pr_debug("%s: IOMMU mapping activated, "
"no device action necessary\n", __FUNCTION__);
/* Direct I/O, IOMMU off */
ppc_md.iommu_dev_setup = iommu_dev_setup_null;
ppc_md.iommu_bus_setup = iommu_bus_setup_null;
}
}
pci_dma_ops = cell_iommu_ops;
}