dma-mapping: introduce DMA range map, supplanting dma_pfn_offset

The new field 'dma_range_map' in struct device is used to facilitate the
use of single or multiple offsets between mapping regions of cpu addrs and
dma addrs.  It subsumes the role of "dev->dma_pfn_offset" which was only
capable of holding a single uniform offset and had no region bounds
checking.

The function of_dma_get_range() has been modified so that it takes a single
argument -- the device node -- and returns a map, NULL, or an error code.
The map is an array that holds the information regarding the DMA regions.
Each range entry contains the address offset, the cpu_start address, the
dma_start address, and the size of the region.

of_dma_configure() is the typical manner to set range offsets but there are
a number of ad hoc assignments to "dev->dma_pfn_offset" in the kernel
driver code.  These cases now invoke the function
dma_direct_set_offset(dev, cpu_addr, dma_addr, size).

Signed-off-by: Jim Quinlan <james.quinlan@broadcom.com>
[hch: various interface cleanups]
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Mathieu Poirier <mathieu.poirier@linaro.org>
Tested-by: Mathieu Poirier <mathieu.poirier@linaro.org>
Tested-by: Nathan Chancellor <natechancellor@gmail.com>
This commit is contained in:
Jim Quinlan 2020-09-17 18:43:40 +02:00 committed by Christoph Hellwig
parent 6eb0233ec2
commit e0d072782c
22 changed files with 285 additions and 118 deletions

View File

@ -12,8 +12,8 @@
#ifndef __arch_pfn_to_dma
static inline dma_addr_t pfn_to_dma(struct device *dev, unsigned long pfn)
{
if (dev)
pfn -= dev->dma_pfn_offset;
if (dev && dev->dma_range_map)
pfn = PFN_DOWN(translate_phys_to_dma(dev, PFN_PHYS(pfn)));
return (dma_addr_t)__pfn_to_bus(pfn);
}
@ -21,9 +21,8 @@ static inline unsigned long dma_to_pfn(struct device *dev, dma_addr_t addr)
{
unsigned long pfn = __bus_to_pfn(addr);
if (dev)
pfn += dev->dma_pfn_offset;
if (dev && dev->dma_range_map)
pfn = PFN_DOWN(translate_dma_to_phys(dev, PFN_PHYS(pfn)));
return pfn;
}

View File

@ -8,6 +8,7 @@
*/
#include <linux/io.h>
#include <linux/of.h>
#include <linux/dma-mapping.h>
#include <linux/init.h>
#include <linux/of_platform.h>
#include <linux/of_address.h>
@ -25,8 +26,6 @@
#include "keystone.h"
#ifdef CONFIG_ARM_LPAE
static unsigned long keystone_dma_pfn_offset __read_mostly;
static int keystone_platform_notifier(struct notifier_block *nb,
unsigned long event, void *data)
{
@ -39,9 +38,12 @@ static int keystone_platform_notifier(struct notifier_block *nb,
return NOTIFY_BAD;
if (!dev->of_node) {
dev->dma_pfn_offset = keystone_dma_pfn_offset;
dev_err(dev, "set dma_pfn_offset%08lx\n",
dev->dma_pfn_offset);
int ret = dma_direct_set_offset(dev, KEYSTONE_HIGH_PHYS_START,
KEYSTONE_LOW_PHYS_START,
KEYSTONE_HIGH_PHYS_SIZE);
dev_err(dev, "set dma_offset%08llx%s\n",
KEYSTONE_HIGH_PHYS_START - KEYSTONE_LOW_PHYS_START,
ret ? " failed" : "");
}
return NOTIFY_OK;
}
@ -54,11 +56,8 @@ static struct notifier_block platform_nb = {
static void __init keystone_init(void)
{
#ifdef CONFIG_ARM_LPAE
if (PHYS_OFFSET >= KEYSTONE_HIGH_PHYS_START) {
keystone_dma_pfn_offset = PFN_DOWN(KEYSTONE_HIGH_PHYS_START -
KEYSTONE_LOW_PHYS_START);
if (PHYS_OFFSET >= KEYSTONE_HIGH_PHYS_START)
bus_register_notifier(&platform_bus_type, &platform_nb);
}
#endif
keystone_pm_runtime_init();
}

View File

@ -41,6 +41,10 @@
__phys_to_pfn(__dma); \
})
#define __arch_dma_to_virt(dev, addr) ({ (void *) (is_lbus_device(dev) ? \
lbus_to_virt(addr) : \
__phys_to_virt(addr)); })
#define __arch_virt_to_dma(dev, addr) ({ unsigned long __addr = (unsigned long)(addr); \
(dma_addr_t) (is_lbus_device(dev) ? \
virt_to_lbus(__addr) : \

View File

@ -12,6 +12,7 @@
#include <linux/io.h>
#include <linux/async.h>
#include <linux/delay.h>
#include <linux/dma-mapping.h>
#include <linux/slab.h>
#include <linux/clk.h>
#include <linux/sh_clk.h>
@ -31,6 +32,8 @@ struct sh7786_pcie_port {
static struct sh7786_pcie_port *sh7786_pcie_ports;
static unsigned int nr_ports;
static unsigned long dma_pfn_offset;
size_t memsize;
u64 memstart;
static struct sh7786_pcie_hwops {
int (*core_init)(void);
@ -301,7 +304,6 @@ static int __init pcie_init(struct sh7786_pcie_port *port)
struct pci_channel *chan = port->hose;
unsigned int data;
phys_addr_t memstart, memend;
size_t memsize;
int ret, i, win;
/* Begin initialization */
@ -368,8 +370,6 @@ static int __init pcie_init(struct sh7786_pcie_port *port)
memstart = ALIGN_DOWN(memstart, memsize);
memsize = roundup_pow_of_two(memend - memstart);
dma_pfn_offset = memstart >> PAGE_SHIFT;
/*
* If there's more than 512MB of memory, we need to roll over to
* LAR1/LAMR1.
@ -487,7 +487,8 @@ int pcibios_map_platform_irq(const struct pci_dev *pdev, u8 slot, u8 pin)
void pcibios_bus_add_device(struct pci_dev *pdev)
{
pdev->dev.dma_pfn_offset = dma_pfn_offset;
dma_direct_set_offset(&pdev->dev, __pa(memory_start),
__pa(memory_start) - memstart, memsize);
}
static int __init sh7786_pcie_core_init(void)

View File

@ -133,7 +133,7 @@ static void sta2x11_map_ep(struct pci_dev *pdev)
struct sta2x11_instance *instance = sta2x11_pdev_to_instance(pdev);
struct device *dev = &pdev->dev;
u32 amba_base, max_amba_addr;
int i;
int i, ret;
if (!instance)
return;
@ -141,7 +141,9 @@ static void sta2x11_map_ep(struct pci_dev *pdev)
pci_read_config_dword(pdev, AHB_BASE(0), &amba_base);
max_amba_addr = amba_base + STA2X11_AMBA_SIZE - 1;
dev->dma_pfn_offset = PFN_DOWN(-amba_base);
ret = dma_direct_set_offset(dev, 0, amba_base, STA2X11_AMBA_SIZE);
if (ret)
dev_err(dev, "sta2x11: could not set DMA offset\n");
dev->bus_dma_limit = max_amba_addr;
pci_set_consistent_dma_mask(pdev, max_amba_addr);

View File

@ -18,6 +18,7 @@
#include <linux/pci.h>
#include <linux/platform_device.h>
#include <linux/slab.h>
#include <linux/dma-mapping.h>
#define IORT_TYPE_MASK(type) (1 << (type))
#define IORT_MSI_TYPE (1 << ACPI_IORT_NODE_ITS_GROUP)
@ -1184,8 +1185,9 @@ void iort_dma_setup(struct device *dev, u64 *dma_addr, u64 *dma_size)
*dma_addr = dmaaddr;
*dma_size = size;
dev->dma_pfn_offset = PFN_DOWN(offset);
dev_dbg(dev, "dma_pfn_offset(%#08llx)\n", offset);
ret = dma_direct_set_offset(dev, dmaaddr + offset, dmaaddr, size);
dev_dbg(dev, "dma_offset(%#08llx)%s\n", offset, ret ? " failed!" : "");
}
static void __init acpi_iort_register_irq(int hwirq, const char *name,

View File

@ -1792,6 +1792,8 @@ static void device_release(struct kobject *kobj)
*/
devres_release_all(dev);
kfree(dev->dma_range_map);
if (dev->release)
dev->release(dev);
else if (dev->type && dev->type->release)

View File

@ -11,6 +11,7 @@
#include <linux/module.h>
#include <linux/of_device.h>
#include <linux/of_graph.h>
#include <linux/dma-mapping.h>
#include <linux/platform_device.h>
#include <linux/reset.h>
@ -811,8 +812,13 @@ static int sun4i_backend_bind(struct device *dev, struct device *master,
* because of an old DT, we need to set the DMA offset by hand
* on our device since the RAM mapping is at 0 for the DMA bus,
* unlike the CPU.
*
* XXX(hch): this has no business in a driver and needs to move
* to the device tree.
*/
drm->dev->dma_pfn_offset = PHYS_PFN_OFFSET;
ret = dma_direct_set_offset(drm->dev, PHYS_OFFSET, 0, SZ_4G);
if (ret)
return ret;
}
backend->engine.node = dev->of_node;

View File

@ -751,7 +751,7 @@ arm_lpae_alloc_pgtable(struct io_pgtable_cfg *cfg)
if (cfg->oas > ARM_LPAE_MAX_ADDR_BITS)
return NULL;
if (!selftest_running && cfg->iommu_dev->dma_pfn_offset) {
if (!selftest_running && cfg->iommu_dev->dma_range_map) {
dev_err(cfg->iommu_dev, "Cannot accommodate DMA offset for IOMMU page tables\n");
return NULL;
}

View File

@ -7,6 +7,7 @@
*/
#include <linux/clk.h>
#include <linux/dma-mapping.h>
#include <linux/interrupt.h>
#include <linux/module.h>
#include <linux/mutex.h>
@ -182,8 +183,14 @@ static int sun4i_csi_probe(struct platform_device *pdev)
if (ret)
return ret;
} else {
/*
* XXX(hch): this has no business in a driver and needs to move
* to the device tree.
*/
#ifdef PHYS_PFN_OFFSET
csi->dev->dma_pfn_offset = PHYS_PFN_OFFSET;
ret = dma_direct_set_offset(csi->dev, PHYS_OFFSET, 0, SZ_4G);
if (ret)
return ret;
#endif
}

View File

@ -899,8 +899,15 @@ static int sun6i_csi_probe(struct platform_device *pdev)
return -ENOMEM;
sdev->dev = &pdev->dev;
/* The DMA bus has the memory mapped at 0 */
sdev->dev->dma_pfn_offset = PHYS_OFFSET >> PAGE_SHIFT;
/*
* The DMA bus has the memory mapped at 0.
*
* XXX(hch): this has no business in a driver and needs to move
* to the device tree.
*/
ret = dma_direct_set_offset(sdev->dev, PHYS_OFFSET, 0, SZ_4G);
if (ret)
return ret;
ret = sun6i_csi_resource_request(sdev, pdev);
if (ret)

View File

@ -13,6 +13,7 @@
#include <linux/sizes.h>
#include <linux/slab.h>
#include <linux/string.h>
#include <linux/dma-direct.h> /* for bus_dma_region */
#include "of_private.h"
@ -937,33 +938,33 @@ void __iomem *of_io_request_and_map(struct device_node *np, int index,
}
EXPORT_SYMBOL(of_io_request_and_map);
#ifdef CONFIG_HAS_DMA
/**
* of_dma_get_range - Get DMA range info
* of_dma_get_range - Get DMA range info and put it into a map array
* @np: device node to get DMA range info
* @dma_addr: pointer to store initial DMA address of DMA range
* @paddr: pointer to store initial CPU address of DMA range
* @size: pointer to store size of DMA range
* @map: dma range structure to return
*
* Look in bottom up direction for the first "dma-ranges" property
* and parse it.
* dma-ranges format:
* and parse it. Put the information into a DMA offset map array.
*
* dma-ranges format:
* DMA addr (dma_addr) : naddr cells
* CPU addr (phys_addr_t) : pna cells
* size : nsize cells
*
* It returns -ENODEV if "dma-ranges" property was not found
* for this device in DT.
* It returns -ENODEV if "dma-ranges" property was not found for this
* device in the DT.
*/
int of_dma_get_range(struct device_node *np, u64 *dma_addr, u64 *paddr, u64 *size)
int of_dma_get_range(struct device_node *np, const struct bus_dma_region **map)
{
struct device_node *node = of_node_get(np);
const __be32 *ranges = NULL;
int len;
int ret = 0;
bool found_dma_ranges = false;
struct of_range_parser parser;
struct of_range range;
u64 dma_start = U64_MAX, dma_end = 0, dma_offset = 0;
struct bus_dma_region *r;
int len, num_ranges = 0;
int ret = 0;
while (node) {
ranges = of_get_property(node, "dma-ranges", &len);
@ -989,49 +990,39 @@ int of_dma_get_range(struct device_node *np, u64 *dma_addr, u64 *paddr, u64 *siz
}
of_dma_range_parser_init(&parser, node);
for_each_of_range(&parser, &range)
num_ranges++;
r = kcalloc(num_ranges + 1, sizeof(*r), GFP_KERNEL);
if (!r) {
ret = -ENOMEM;
goto out;
}
/*
* Record all info in the generic DMA ranges array for struct device.
*/
*map = r;
of_dma_range_parser_init(&parser, node);
for_each_of_range(&parser, &range) {
pr_debug("dma_addr(%llx) cpu_addr(%llx) size(%llx)\n",
range.bus_addr, range.cpu_addr, range.size);
if (dma_offset && range.cpu_addr - range.bus_addr != dma_offset) {
pr_warn("Can't handle multiple dma-ranges with different offsets on node(%pOF)\n", node);
/* Don't error out as we'd break some existing DTs */
continue;
}
if (range.cpu_addr == OF_BAD_ADDR) {
pr_err("translation of DMA address(%llx) to CPU address failed node(%pOF)\n",
range.bus_addr, node);
continue;
}
dma_offset = range.cpu_addr - range.bus_addr;
/* Take lower and upper limits */
if (range.bus_addr < dma_start)
dma_start = range.bus_addr;
if (range.bus_addr + range.size > dma_end)
dma_end = range.bus_addr + range.size;
r->cpu_start = range.cpu_addr;
r->dma_start = range.bus_addr;
r->size = range.size;
r->offset = range.cpu_addr - range.bus_addr;
r++;
}
if (dma_start >= dma_end) {
ret = -EINVAL;
pr_debug("Invalid DMA ranges configuration on node(%pOF)\n",
node);
goto out;
}
*dma_addr = dma_start;
*size = dma_end - dma_start;
*paddr = dma_start + dma_offset;
pr_debug("final: dma_addr(%llx) cpu_addr(%llx) size(%llx)\n",
*dma_addr, *paddr, *size);
out:
of_node_put(node);
return ret;
}
#endif /* CONFIG_HAS_DMA */
/**
* of_dma_is_coherent - Check if device is coherent

View File

@ -5,7 +5,7 @@
#include <linux/of_device.h>
#include <linux/of_address.h>
#include <linux/of_iommu.h>
#include <linux/dma-mapping.h>
#include <linux/dma-direct.h> /* for bus_dma_region */
#include <linux/init.h>
#include <linux/module.h>
#include <linux/mod_devicetable.h>
@ -90,14 +90,14 @@ int of_device_add(struct platform_device *ofdev)
int of_dma_configure_id(struct device *dev, struct device_node *np,
bool force_dma, const u32 *id)
{
u64 dma_addr, paddr, size = 0;
int ret;
bool coherent;
unsigned long offset;
const struct iommu_ops *iommu;
u64 mask, end;
const struct bus_dma_region *map = NULL;
dma_addr_t dma_start = 0;
u64 mask, end, size = 0;
bool coherent;
int ret;
ret = of_dma_get_range(np, &dma_addr, &paddr, &size);
ret = of_dma_get_range(np, &map);
if (ret < 0) {
/*
* For legacy reasons, we have to assume some devices need
@ -106,26 +106,35 @@ int of_dma_configure_id(struct device *dev, struct device_node *np,
*/
if (!force_dma)
return ret == -ENODEV ? 0 : ret;
dma_addr = offset = 0;
} else {
offset = PFN_DOWN(paddr - dma_addr);
const struct bus_dma_region *r = map;
dma_addr_t dma_end = 0;
/* Determine the overall bounds of all DMA regions */
for (dma_start = ~(dma_addr_t)0; r->size; r++) {
/* Take lower and upper limits */
if (r->dma_start < dma_start)
dma_start = r->dma_start;
if (r->dma_start + r->size > dma_end)
dma_end = r->dma_start + r->size;
}
size = dma_end - dma_start;
/*
* Add a work around to treat the size as mask + 1 in case
* it is defined in DT as a mask.
*/
if (size & 1) {
dev_warn(dev, "Invalid size 0x%llx for dma-range\n",
dev_warn(dev, "Invalid size 0x%llx for dma-range(s)\n",
size);
size = size + 1;
}
if (!size) {
dev_err(dev, "Adjusted size 0x%llx invalid\n", size);
kfree(map);
return -EINVAL;
}
dev_dbg(dev, "dma_pfn_offset(%#08lx)\n", offset);
}
/*
@ -144,13 +153,11 @@ int of_dma_configure_id(struct device *dev, struct device_node *np,
else if (!size)
size = 1ULL << 32;
dev->dma_pfn_offset = offset;
/*
* Limit coherent and dma mask based on size and default mask
* set by the driver.
*/
end = dma_addr + size - 1;
end = dma_start + size - 1;
mask = DMA_BIT_MASK(ilog2(end) + 1);
dev->coherent_dma_mask &= mask;
*dev->dma_mask &= mask;
@ -163,14 +170,17 @@ int of_dma_configure_id(struct device *dev, struct device_node *np,
coherent ? " " : " not ");
iommu = of_iommu_configure(dev, np, id);
if (PTR_ERR(iommu) == -EPROBE_DEFER)
if (PTR_ERR(iommu) == -EPROBE_DEFER) {
kfree(map);
return -EPROBE_DEFER;
}
dev_dbg(dev, "device is%sbehind an iommu\n",
iommu ? " " : " not ");
arch_setup_dma_ops(dev, dma_addr, size, iommu, coherent);
arch_setup_dma_ops(dev, dma_start, size, iommu, coherent);
dev->dma_range_map = map;
return 0;
}
EXPORT_SYMBOL_GPL(of_dma_configure_id);

View File

@ -157,12 +157,13 @@ extern void __of_sysfs_remove_bin_file(struct device_node *np,
extern int of_bus_n_addr_cells(struct device_node *np);
extern int of_bus_n_size_cells(struct device_node *np);
#ifdef CONFIG_OF_ADDRESS
extern int of_dma_get_range(struct device_node *np, u64 *dma_addr,
u64 *paddr, u64 *size);
struct bus_dma_region;
#if defined(CONFIG_OF_ADDRESS) && defined(CONFIG_HAS_DMA)
int of_dma_get_range(struct device_node *np,
const struct bus_dma_region **map);
#else
static inline int of_dma_get_range(struct device_node *np, u64 *dma_addr,
u64 *paddr, u64 *size)
static inline int of_dma_get_range(struct device_node *np,
const struct bus_dma_region **map)
{
return -ENODEV;
}

View File

@ -7,6 +7,7 @@
#include <linux/memblock.h>
#include <linux/clk.h>
#include <linux/dma-direct.h> /* to test phys_to_dma/dma_to_phys */
#include <linux/err.h>
#include <linux/errno.h>
#include <linux/hashtable.h>
@ -869,10 +870,11 @@ static void __init of_unittest_changeset(void)
}
static void __init of_unittest_dma_ranges_one(const char *path,
u64 expect_dma_addr, u64 expect_paddr, u64 expect_size)
u64 expect_dma_addr, u64 expect_paddr)
{
#ifdef CONFIG_HAS_DMA
struct device_node *np;
u64 dma_addr, paddr, size;
const struct bus_dma_region *map = NULL;
int rc;
np = of_find_node_by_path(path);
@ -881,28 +883,40 @@ static void __init of_unittest_dma_ranges_one(const char *path,
return;
}
rc = of_dma_get_range(np, &dma_addr, &paddr, &size);
rc = of_dma_get_range(np, &map);
unittest(!rc, "of_dma_get_range failed on node %pOF rc=%i\n", np, rc);
if (!rc) {
unittest(size == expect_size,
"of_dma_get_range wrong size on node %pOF size=%llx\n", np, size);
phys_addr_t paddr;
dma_addr_t dma_addr;
struct device dev_bogus;
dev_bogus.dma_range_map = map;
paddr = dma_to_phys(&dev_bogus, expect_dma_addr);
dma_addr = phys_to_dma(&dev_bogus, expect_paddr);
unittest(paddr == expect_paddr,
"of_dma_get_range wrong phys addr (%llx) on node %pOF", paddr, np);
"of_dma_get_range: wrong phys addr %pap (expecting %llx) on node %pOF\n",
&paddr, expect_paddr, np);
unittest(dma_addr == expect_dma_addr,
"of_dma_get_range wrong DMA addr (%llx) on node %pOF", dma_addr, np);
"of_dma_get_range: wrong DMA addr %pad (expecting %llx) on node %pOF\n",
&dma_addr, expect_dma_addr, np);
kfree(map);
}
of_node_put(np);
#endif
}
static void __init of_unittest_parse_dma_ranges(void)
{
of_unittest_dma_ranges_one("/testcase-data/address-tests/device@70000000",
0x0, 0x20000000, 0x40000000);
0x0, 0x20000000);
of_unittest_dma_ranges_one("/testcase-data/address-tests/bus@80000000/device@1000",
0x100000000, 0x20000000, 0x2000000000);
0x100000000, 0x20000000);
of_unittest_dma_ranges_one("/testcase-data/address-tests/pci@90000000",
0x80000000, 0x20000000, 0x10000000);
0x80000000, 0x20000000);
}
static void __init of_unittest_pci_dma_ranges(void)

View File

@ -23,6 +23,7 @@
#include <linux/slab.h>
#include <linux/mutex.h>
#include <linux/dma-mapping.h>
#include <linux/dma-direct.h> /* XXX: pokes into bus_dma_range */
#include <linux/firmware.h>
#include <linux/string.h>
#include <linux/debugfs.h>
@ -458,6 +459,25 @@ static void rproc_rvdev_release(struct device *dev)
kfree(rvdev);
}
static int copy_dma_range_map(struct device *to, struct device *from)
{
const struct bus_dma_region *map = from->dma_range_map, *new_map, *r;
int num_ranges = 0;
if (!map)
return 0;
for (r = map; r->size; r++)
num_ranges++;
new_map = kmemdup(map, array_size(num_ranges + 1, sizeof(*map)),
GFP_KERNEL);
if (!new_map)
return -ENOMEM;
to->dma_range_map = new_map;
return 0;
}
/**
* rproc_handle_vdev() - handle a vdev fw resource
* @rproc: the remote processor
@ -529,7 +549,9 @@ static int rproc_handle_vdev(struct rproc *rproc, struct fw_rsc_vdev *rsc,
/* Initialise vdev subdevice */
snprintf(name, sizeof(name), "vdev%dbuffer", rvdev->index);
rvdev->dev.parent = &rproc->dev;
rvdev->dev.dma_pfn_offset = rproc->dev.parent->dma_pfn_offset;
ret = copy_dma_range_map(&rvdev->dev, rproc->dev.parent);
if (ret)
return ret;
rvdev->dev.release = rproc_rvdev_release;
dev_set_name(&rvdev->dev, "%s#%s", dev_name(rvdev->dev.parent), name);
dev_set_drvdata(&rvdev->dev, rvdev);

View File

@ -227,11 +227,17 @@ int cedrus_hw_probe(struct cedrus_dev *dev)
* the RAM offset to the physcal addresses.
*
* This information will eventually be obtained from device-tree.
*
* XXX(hch): this has no business in a driver and needs to move
* to the device tree.
*/
#ifdef PHYS_PFN_OFFSET
if (!(variant->quirks & CEDRUS_QUIRK_NO_DMA_OFFSET))
dev->dev->dma_pfn_offset = PHYS_PFN_OFFSET;
if (!(variant->quirks & CEDRUS_QUIRK_NO_DMA_OFFSET)) {
ret = dma_direct_set_offset(dev->dev, PHYS_OFFSET, 0, SZ_4G);
if (ret)
return ret;
}
#endif
ret = of_reserved_mem_device_init(dev->dev);

View File

@ -466,7 +466,7 @@ struct dev_links_info {
* such descriptors.
* @bus_dma_limit: Limit of an upstream bridge or bus which imposes a smaller
* DMA limit than the device itself supports.
* @dma_pfn_offset: offset of DMA memory range relatively of RAM
* @dma_range_map: map for DMA memory ranges relative to that of RAM
* @dma_parms: A low level driver may set these to teach IOMMU code about
* segment limitations.
* @dma_pools: Dma pools (if dma'ble device).
@ -561,7 +561,7 @@ struct device {
64 bit addresses for consistent
allocations such descriptors. */
u64 bus_dma_limit; /* upstream dma constraint */
unsigned long dma_pfn_offset;
const struct bus_dma_region *dma_range_map;
struct device_dma_parameters *dma_parms;

View File

@ -14,6 +14,41 @@
extern unsigned int zone_dma_bits;
/*
* Record the mapping of CPU physical to DMA addresses for a given region.
*/
struct bus_dma_region {
phys_addr_t cpu_start;
dma_addr_t dma_start;
u64 size;
u64 offset;
};
static inline dma_addr_t translate_phys_to_dma(struct device *dev,
phys_addr_t paddr)
{
const struct bus_dma_region *m;
for (m = dev->dma_range_map; m->size; m++)
if (paddr >= m->cpu_start && paddr - m->cpu_start < m->size)
return (dma_addr_t)paddr - m->offset;
/* make sure dma_capable fails when no translation is available */
return DMA_MAPPING_ERROR;
}
static inline phys_addr_t translate_dma_to_phys(struct device *dev,
dma_addr_t dma_addr)
{
const struct bus_dma_region *m;
for (m = dev->dma_range_map; m->size; m++)
if (dma_addr >= m->dma_start && dma_addr - m->dma_start < m->size)
return (phys_addr_t)dma_addr + m->offset;
return (phys_addr_t)-1;
}
#ifdef CONFIG_ARCH_HAS_PHYS_TO_DMA
#include <asm/dma-direct.h>
#ifndef phys_to_dma_unencrypted
@ -23,9 +58,9 @@ extern unsigned int zone_dma_bits;
static inline dma_addr_t phys_to_dma_unencrypted(struct device *dev,
phys_addr_t paddr)
{
dma_addr_t dev_addr = (dma_addr_t)paddr;
return dev_addr - ((dma_addr_t)dev->dma_pfn_offset << PAGE_SHIFT);
if (dev->dma_range_map)
return translate_phys_to_dma(dev, paddr);
return paddr;
}
/*
@ -39,10 +74,14 @@ static inline dma_addr_t phys_to_dma(struct device *dev, phys_addr_t paddr)
return __sme_set(phys_to_dma_unencrypted(dev, paddr));
}
static inline phys_addr_t dma_to_phys(struct device *dev, dma_addr_t dev_addr)
static inline phys_addr_t dma_to_phys(struct device *dev, dma_addr_t dma_addr)
{
phys_addr_t paddr = (phys_addr_t)dev_addr +
((phys_addr_t)dev->dma_pfn_offset << PAGE_SHIFT);
phys_addr_t paddr;
if (dev->dma_range_map)
paddr = translate_dma_to_phys(dev, dma_addr);
else
paddr = dma_addr;
return __sme_clr(paddr);
}
@ -62,6 +101,8 @@ static inline bool dma_capable(struct device *dev, dma_addr_t addr, size_t size,
{
dma_addr_t end = addr + size - 1;
if (addr == DMA_MAPPING_ERROR)
return false;
if (is_ram && !IS_ENABLED(CONFIG_ARCH_DMA_ADDR_T_64BIT) &&
min(addr, end) < phys_to_dma(dev, PFN_PHYS(min_low_pfn)))
return false;

View File

@ -730,4 +730,11 @@ static inline int dma_mmap_wc(struct device *dev,
#define dma_unmap_len_set(PTR, LEN_NAME, VAL) do { } while (0)
#endif
#endif
/*
* Legacy interface to set up the dma offset map. Drivers really should not
* actually use it, but we have a few legacy cases left.
*/
int dma_direct_set_offset(struct device *dev, phys_addr_t cpu_start,
dma_addr_t dma_start, u64 size);
#endif /* _LINUX_DMA_MAPPING_H */

View File

@ -7,7 +7,7 @@
#include <linux/slab.h>
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/dma-mapping.h>
#include <linux/dma-direct.h>
struct dma_coherent_mem {
void *virt_base;
@ -32,9 +32,8 @@ static inline dma_addr_t dma_get_device_base(struct device *dev,
struct dma_coherent_mem * mem)
{
if (mem->use_dev_dma_pfn_offset)
return (mem->pfn_base - dev->dma_pfn_offset) << PAGE_SHIFT;
else
return mem->device_base;
return phys_to_dma(dev, PFN_PHYS(mem->pfn_base));
return mem->device_base;
}
static int dma_init_coherent_memory(phys_addr_t phys_addr,

View File

@ -13,6 +13,7 @@
#include <linux/pfn.h>
#include <linux/vmalloc.h>
#include <linux/set_memory.h>
#include <linux/slab.h>
/*
* Most architectures use ZONE_DMA for the first 16 Megabytes, but some use it
@ -66,8 +67,12 @@ static gfp_t dma_direct_optimal_gfp_mask(struct device *dev, u64 dma_mask,
static bool dma_coherent_ok(struct device *dev, phys_addr_t phys, size_t size)
{
return phys_to_dma_direct(dev, phys) + size - 1 <=
min_not_zero(dev->coherent_dma_mask, dev->bus_dma_limit);
dma_addr_t dma_addr = phys_to_dma_direct(dev, phys);
if (dma_addr == DMA_MAPPING_ERROR)
return false;
return dma_addr + size - 1 <=
min_not_zero(dev->coherent_dma_mask, dev->bus_dma_limit);
}
/*
@ -461,3 +466,45 @@ bool dma_direct_need_sync(struct device *dev, dma_addr_t dma_addr)
return !dev_is_dma_coherent(dev) ||
is_swiotlb_buffer(dma_to_phys(dev, dma_addr));
}
/**
* dma_direct_set_offset - Assign scalar offset for a single DMA range.
* @dev: device pointer; needed to "own" the alloced memory.
* @cpu_start: beginning of memory region covered by this offset.
* @dma_start: beginning of DMA/PCI region covered by this offset.
* @size: size of the region.
*
* This is for the simple case of a uniform offset which cannot
* be discovered by "dma-ranges".
*
* It returns -ENOMEM if out of memory, -EINVAL if a map
* already exists, 0 otherwise.
*
* Note: any call to this from a driver is a bug. The mapping needs
* to be described by the device tree or other firmware interfaces.
*/
int dma_direct_set_offset(struct device *dev, phys_addr_t cpu_start,
dma_addr_t dma_start, u64 size)
{
struct bus_dma_region *map;
u64 offset = (u64)cpu_start - (u64)dma_start;
if (dev->dma_range_map) {
dev_err(dev, "attempt to add DMA range to existing map\n");
return -EINVAL;
}
if (!offset)
return 0;
map = kcalloc(2, sizeof(*map), GFP_KERNEL);
if (!map)
return -ENOMEM;
map[0].cpu_start = cpu_start;
map[0].dma_start = dma_start;
map[0].offset = offset;
map[0].size = size;
dev->dma_range_map = map;
return 0;
}
EXPORT_SYMBOL_GPL(dma_direct_set_offset);