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kernel-ark/arch/x86/pci/sta2x11-fixup.c
Akinobu Mita 9c5a362142 x86: enable DMA CMA with swiotlb 
The DMA Contiguous Memory Allocator support on x86 is disabled when
swiotlb config option is enabled.  So DMA CMA is always disabled on
x86_64 because swiotlb is always enabled.  This attempts to support for
DMA CMA with enabling swiotlb config option.

The contiguous memory allocator on x86 is integrated in the function
dma_generic_alloc_coherent() which is .alloc callback in nommu_dma_ops
for dma_alloc_coherent().

x86_swiotlb_alloc_coherent() which is .alloc callback in swiotlb_dma_ops
tries to allocate with dma_generic_alloc_coherent() firstly and then
swiotlb_alloc_coherent() is called as a fallback.

The main part of supporting DMA CMA with swiotlb is that changing
x86_swiotlb_free_coherent() which is .free callback in swiotlb_dma_ops
for dma_free_coherent() so that it can distinguish memory allocated by
dma_generic_alloc_coherent() from one allocated by
swiotlb_alloc_coherent() and release it with dma_generic_free_coherent()
which can handle contiguous memory.  This change requires making
is_swiotlb_buffer() global function.

This also needs to change .free callback in the dma_map_ops for amd_gart
and sta2x11, because these dma_ops are also using
dma_generic_alloc_coherent().

Signed-off-by: Akinobu Mita <akinobu.mita@gmail.com>
Acked-by: Marek Szyprowski <m.szyprowski@samsung.com>
Acked-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Cc: David Woodhouse <dwmw2@infradead.org>
Cc: Don Dutile <ddutile@redhat.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Andi Kleen <andi@firstfloor.org>
Cc: Yinghai Lu <yinghai@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2014-06-04 16:53:57 -07:00

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/*
* arch/x86/pci/sta2x11-fixup.c
* glue code for lib/swiotlb.c and DMA translation between STA2x11
* AMBA memory mapping and the X86 memory mapping
*
* ST Microelectronics ConneXt (STA2X11/STA2X10)
*
* Copyright (c) 2010-2011 Wind River Systems, Inc.
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License version 2 as
* published by the Free Software Foundation.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
* See the GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
*
*/
#include <linux/pci.h>
#include <linux/pci_ids.h>
#include <linux/export.h>
#include <linux/list.h>
#define STA2X11_SWIOTLB_SIZE (4*1024*1024)
extern int swiotlb_late_init_with_default_size(size_t default_size);
/*
* We build a list of bus numbers that are under the ConneXt. The
* main bridge hosts 4 busses, which are the 4 endpoints, in order.
*/
#define STA2X11_NR_EP 4 /* 0..3 included */
#define STA2X11_NR_FUNCS 8 /* 0..7 included */
#define STA2X11_AMBA_SIZE (512 << 20)
struct sta2x11_ahb_regs { /* saved during suspend */
u32 base, pexlbase, pexhbase, crw;
};
struct sta2x11_mapping {
u32 amba_base;
int is_suspended;
struct sta2x11_ahb_regs regs[STA2X11_NR_FUNCS];
};
struct sta2x11_instance {
struct list_head list;
int bus0;
struct sta2x11_mapping map[STA2X11_NR_EP];
};
static LIST_HEAD(sta2x11_instance_list);
/* At probe time, record new instances of this bridge (likely one only) */
static void sta2x11_new_instance(struct pci_dev *pdev)
{
struct sta2x11_instance *instance;
instance = kzalloc(sizeof(*instance), GFP_ATOMIC);
if (!instance)
return;
/* This has a subordinate bridge, with 4 more-subordinate ones */
instance->bus0 = pdev->subordinate->number + 1;
if (list_empty(&sta2x11_instance_list)) {
int size = STA2X11_SWIOTLB_SIZE;
/* First instance: register your own swiotlb area */
dev_info(&pdev->dev, "Using SWIOTLB (size %i)\n", size);
if (swiotlb_late_init_with_default_size(size))
dev_emerg(&pdev->dev, "init swiotlb failed\n");
}
list_add(&instance->list, &sta2x11_instance_list);
}
DECLARE_PCI_FIXUP_ENABLE(PCI_VENDOR_ID_STMICRO, 0xcc17, sta2x11_new_instance);
/*
* Utility functions used in this file from below
*/
static struct sta2x11_instance *sta2x11_pdev_to_instance(struct pci_dev *pdev)
{
struct sta2x11_instance *instance;
int ep;
list_for_each_entry(instance, &sta2x11_instance_list, list) {
ep = pdev->bus->number - instance->bus0;
if (ep >= 0 && ep < STA2X11_NR_EP)
return instance;
}
return NULL;
}
static int sta2x11_pdev_to_ep(struct pci_dev *pdev)
{
struct sta2x11_instance *instance;
instance = sta2x11_pdev_to_instance(pdev);
if (!instance)
return -1;
return pdev->bus->number - instance->bus0;
}
static struct sta2x11_mapping *sta2x11_pdev_to_mapping(struct pci_dev *pdev)
{
struct sta2x11_instance *instance;
int ep;
instance = sta2x11_pdev_to_instance(pdev);
if (!instance)
return NULL;
ep = sta2x11_pdev_to_ep(pdev);
return instance->map + ep;
}
/* This is exported, as some devices need to access the MFD registers */
struct sta2x11_instance *sta2x11_get_instance(struct pci_dev *pdev)
{
return sta2x11_pdev_to_instance(pdev);
}
EXPORT_SYMBOL(sta2x11_get_instance);
/**
* p2a - Translate physical address to STA2x11 AMBA address,
* used for DMA transfers to STA2x11
* @p: Physical address
* @pdev: PCI device (must be hosted within the connext)
*/
static dma_addr_t p2a(dma_addr_t p, struct pci_dev *pdev)
{
struct sta2x11_mapping *map;
dma_addr_t a;
map = sta2x11_pdev_to_mapping(pdev);
a = p + map->amba_base;
return a;
}
/**
* a2p - Translate STA2x11 AMBA address to physical address
* used for DMA transfers from STA2x11
* @a: STA2x11 AMBA address
* @pdev: PCI device (must be hosted within the connext)
*/
static dma_addr_t a2p(dma_addr_t a, struct pci_dev *pdev)
{
struct sta2x11_mapping *map;
dma_addr_t p;
map = sta2x11_pdev_to_mapping(pdev);
p = a - map->amba_base;
return p;
}
/**
* sta2x11_swiotlb_alloc_coherent - Allocate swiotlb bounce buffers
* returns virtual address. This is the only "special" function here.
* @dev: PCI device
* @size: Size of the buffer
* @dma_handle: DMA address
* @flags: memory flags
*/
static void *sta2x11_swiotlb_alloc_coherent(struct device *dev,
size_t size,
dma_addr_t *dma_handle,
gfp_t flags,
struct dma_attrs *attrs)
{
void *vaddr;
vaddr = x86_swiotlb_alloc_coherent(dev, size, dma_handle, flags, attrs);
*dma_handle = p2a(*dma_handle, to_pci_dev(dev));
return vaddr;
}
/* We have our own dma_ops: the same as swiotlb but from alloc (above) */
static struct dma_map_ops sta2x11_dma_ops = {
.alloc = sta2x11_swiotlb_alloc_coherent,
.free = x86_swiotlb_free_coherent,
.map_page = swiotlb_map_page,
.unmap_page = swiotlb_unmap_page,
.map_sg = swiotlb_map_sg_attrs,
.unmap_sg = swiotlb_unmap_sg_attrs,
.sync_single_for_cpu = swiotlb_sync_single_for_cpu,
.sync_single_for_device = swiotlb_sync_single_for_device,
.sync_sg_for_cpu = swiotlb_sync_sg_for_cpu,
.sync_sg_for_device = swiotlb_sync_sg_for_device,
.mapping_error = swiotlb_dma_mapping_error,
.dma_supported = NULL, /* FIXME: we should use this instead! */
};
/* At setup time, we use our own ops if the device is a ConneXt one */
static void sta2x11_setup_pdev(struct pci_dev *pdev)
{
struct sta2x11_instance *instance = sta2x11_pdev_to_instance(pdev);
if (!instance) /* either a sta2x11 bridge or another ST device */
return;
pci_set_consistent_dma_mask(pdev, STA2X11_AMBA_SIZE - 1);
pci_set_dma_mask(pdev, STA2X11_AMBA_SIZE - 1);
pdev->dev.archdata.dma_ops = &sta2x11_dma_ops;
/* We must enable all devices as master, for audio DMA to work */
pci_set_master(pdev);
}
DECLARE_PCI_FIXUP_ENABLE(PCI_VENDOR_ID_STMICRO, PCI_ANY_ID, sta2x11_setup_pdev);
/*
* The following three functions are exported (used in swiotlb: FIXME)
*/
/**
* dma_capable - Check if device can manage DMA transfers (FIXME: kill it)
* @dev: device for a PCI device
* @addr: DMA address
* @size: DMA size
*/
bool dma_capable(struct device *dev, dma_addr_t addr, size_t size)
{
struct sta2x11_mapping *map;
if (dev->archdata.dma_ops != &sta2x11_dma_ops) {
if (!dev->dma_mask)
return false;
return addr + size - 1 <= *dev->dma_mask;
}
map = sta2x11_pdev_to_mapping(to_pci_dev(dev));
if (!map || (addr < map->amba_base))
return false;
if (addr + size >= map->amba_base + STA2X11_AMBA_SIZE) {
return false;
}
return true;
}
/**
* phys_to_dma - Return the DMA AMBA address used for this STA2x11 device
* @dev: device for a PCI device
* @paddr: Physical address
*/
dma_addr_t phys_to_dma(struct device *dev, phys_addr_t paddr)
{
if (dev->archdata.dma_ops != &sta2x11_dma_ops)
return paddr;
return p2a(paddr, to_pci_dev(dev));
}
/**
* dma_to_phys - Return the physical address used for this STA2x11 DMA address
* @dev: device for a PCI device
* @daddr: STA2x11 AMBA DMA address
*/
phys_addr_t dma_to_phys(struct device *dev, dma_addr_t daddr)
{
if (dev->archdata.dma_ops != &sta2x11_dma_ops)
return daddr;
return a2p(daddr, to_pci_dev(dev));
}
/*
* At boot we must set up the mappings for the pcie-to-amba bridge.
* It involves device access, and the same happens at suspend/resume time
*/
#define AHB_MAPB 0xCA4
#define AHB_CRW(i) (AHB_MAPB + 0 + (i) * 0x10)
#define AHB_CRW_SZMASK 0xfffffc00UL
#define AHB_CRW_ENABLE (1 << 0)
#define AHB_CRW_WTYPE_MEM (2 << 1)
#define AHB_CRW_ROE (1UL << 3) /* Relax Order Ena */
#define AHB_CRW_NSE (1UL << 4) /* No Snoop Enable */
#define AHB_BASE(i) (AHB_MAPB + 4 + (i) * 0x10)
#define AHB_PEXLBASE(i) (AHB_MAPB + 8 + (i) * 0x10)
#define AHB_PEXHBASE(i) (AHB_MAPB + 12 + (i) * 0x10)
/* At probe time, enable mapping for each endpoint, using the pdev */
static void sta2x11_map_ep(struct pci_dev *pdev)
{
struct sta2x11_mapping *map = sta2x11_pdev_to_mapping(pdev);
int i;
if (!map)
return;
pci_read_config_dword(pdev, AHB_BASE(0), &map->amba_base);
/* Configure AHB mapping */
pci_write_config_dword(pdev, AHB_PEXLBASE(0), 0);
pci_write_config_dword(pdev, AHB_PEXHBASE(0), 0);
pci_write_config_dword(pdev, AHB_CRW(0), STA2X11_AMBA_SIZE |
AHB_CRW_WTYPE_MEM | AHB_CRW_ENABLE);
/* Disable all the other windows */
for (i = 1; i < STA2X11_NR_FUNCS; i++)
pci_write_config_dword(pdev, AHB_CRW(i), 0);
dev_info(&pdev->dev,
"sta2x11: Map EP %i: AMBA address %#8x-%#8x\n",
sta2x11_pdev_to_ep(pdev), map->amba_base,
map->amba_base + STA2X11_AMBA_SIZE - 1);
}
DECLARE_PCI_FIXUP_ENABLE(PCI_VENDOR_ID_STMICRO, PCI_ANY_ID, sta2x11_map_ep);
#ifdef CONFIG_PM /* Some register values must be saved and restored */
static void suspend_mapping(struct pci_dev *pdev)
{
struct sta2x11_mapping *map = sta2x11_pdev_to_mapping(pdev);
int i;
if (!map)
return;
if (map->is_suspended)
return;
map->is_suspended = 1;
/* Save all window configs */
for (i = 0; i < STA2X11_NR_FUNCS; i++) {
struct sta2x11_ahb_regs *regs = map->regs + i;
pci_read_config_dword(pdev, AHB_BASE(i), &regs->base);
pci_read_config_dword(pdev, AHB_PEXLBASE(i), &regs->pexlbase);
pci_read_config_dword(pdev, AHB_PEXHBASE(i), &regs->pexhbase);
pci_read_config_dword(pdev, AHB_CRW(i), &regs->crw);
}
}
DECLARE_PCI_FIXUP_SUSPEND(PCI_VENDOR_ID_STMICRO, PCI_ANY_ID, suspend_mapping);
static void resume_mapping(struct pci_dev *pdev)
{
struct sta2x11_mapping *map = sta2x11_pdev_to_mapping(pdev);
int i;
if (!map)
return;
if (!map->is_suspended)
goto out;
map->is_suspended = 0;
/* Restore all window configs */
for (i = 0; i < STA2X11_NR_FUNCS; i++) {
struct sta2x11_ahb_regs *regs = map->regs + i;
pci_write_config_dword(pdev, AHB_BASE(i), regs->base);
pci_write_config_dword(pdev, AHB_PEXLBASE(i), regs->pexlbase);
pci_write_config_dword(pdev, AHB_PEXHBASE(i), regs->pexhbase);
pci_write_config_dword(pdev, AHB_CRW(i), regs->crw);
}
out:
pci_set_master(pdev); /* Like at boot, enable master on all devices */
}
DECLARE_PCI_FIXUP_RESUME(PCI_VENDOR_ID_STMICRO, PCI_ANY_ID, resume_mapping);
#endif /* CONFIG_PM */
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