linux/drivers/iommu/tegra-gart.c
Hiroshi DOYU 774dfc9bb7 iommu/tegra: gart: Fix register offset correctly
DT passes the exact GART register ranges without any overlapping with
MC register ranges. GART register offset needs to be adjusted by one
passed by DT correctly.

Signed-off-by: Hiroshi DOYU <hdoyu@nvidia.com>
Acked-by: Stephen Warren <swarren@wwwdotorg.org>
Signed-off-by: Joerg Roedel <joerg.roedel@amd.com>
2012-05-11 11:42:05 +02:00

464 lines
11 KiB
C

/*
* IOMMU API for GART in Tegra20
*
* Copyright (c) 2010-2012, NVIDIA CORPORATION. All rights reserved.
*
* This program is free software; you can redistribute it and/or modify it
* under the terms and conditions of the GNU General Public License,
* version 2, as published by the Free Software Foundation.
*
* This program is distributed in the hope 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.,
* 51 Franklin St - Fifth Floor, Boston, MA 02110-1301 USA.
*/
#define pr_fmt(fmt) "%s(): " fmt, __func__
#include <linux/module.h>
#include <linux/platform_device.h>
#include <linux/spinlock.h>
#include <linux/slab.h>
#include <linux/vmalloc.h>
#include <linux/mm.h>
#include <linux/list.h>
#include <linux/device.h>
#include <linux/io.h>
#include <linux/iommu.h>
#include <linux/of.h>
#include <asm/cacheflush.h>
/* bitmap of the page sizes currently supported */
#define GART_IOMMU_PGSIZES (SZ_4K)
#define GART_REG_BASE 0x24
#define GART_CONFIG (0x24 - GART_REG_BASE)
#define GART_ENTRY_ADDR (0x28 - GART_REG_BASE)
#define GART_ENTRY_DATA (0x2c - GART_REG_BASE)
#define GART_ENTRY_PHYS_ADDR_VALID (1 << 31)
#define GART_PAGE_SHIFT 12
#define GART_PAGE_SIZE (1 << GART_PAGE_SHIFT)
#define GART_PAGE_MASK \
(~(GART_PAGE_SIZE - 1) & ~GART_ENTRY_PHYS_ADDR_VALID)
struct gart_client {
struct device *dev;
struct list_head list;
};
struct gart_device {
void __iomem *regs;
u32 *savedata;
u32 page_count; /* total remappable size */
dma_addr_t iovmm_base; /* offset to vmm_area */
spinlock_t pte_lock; /* for pagetable */
struct list_head client;
spinlock_t client_lock; /* for client list */
struct device *dev;
};
static struct gart_device *gart_handle; /* unique for a system */
#define GART_PTE(_pfn) \
(GART_ENTRY_PHYS_ADDR_VALID | ((_pfn) << PAGE_SHIFT))
/*
* Any interaction between any block on PPSB and a block on APB or AHB
* must have these read-back to ensure the APB/AHB bus transaction is
* complete before initiating activity on the PPSB block.
*/
#define FLUSH_GART_REGS(gart) ((void)readl((gart)->regs + GART_CONFIG))
#define for_each_gart_pte(gart, iova) \
for (iova = gart->iovmm_base; \
iova < gart->iovmm_base + GART_PAGE_SIZE * gart->page_count; \
iova += GART_PAGE_SIZE)
static inline void gart_set_pte(struct gart_device *gart,
unsigned long offs, u32 pte)
{
writel(offs, gart->regs + GART_ENTRY_ADDR);
writel(pte, gart->regs + GART_ENTRY_DATA);
dev_dbg(gart->dev, "%s %08lx:%08x\n",
pte ? "map" : "unmap", offs, pte & GART_PAGE_MASK);
}
static inline unsigned long gart_read_pte(struct gart_device *gart,
unsigned long offs)
{
unsigned long pte;
writel(offs, gart->regs + GART_ENTRY_ADDR);
pte = readl(gart->regs + GART_ENTRY_DATA);
return pte;
}
static void do_gart_setup(struct gart_device *gart, const u32 *data)
{
unsigned long iova;
for_each_gart_pte(gart, iova)
gart_set_pte(gart, iova, data ? *(data++) : 0);
writel(1, gart->regs + GART_CONFIG);
FLUSH_GART_REGS(gart);
}
#ifdef DEBUG
static void gart_dump_table(struct gart_device *gart)
{
unsigned long iova;
unsigned long flags;
spin_lock_irqsave(&gart->pte_lock, flags);
for_each_gart_pte(gart, iova) {
unsigned long pte;
pte = gart_read_pte(gart, iova);
dev_dbg(gart->dev, "%s %08lx:%08lx\n",
(GART_ENTRY_PHYS_ADDR_VALID & pte) ? "v" : " ",
iova, pte & GART_PAGE_MASK);
}
spin_unlock_irqrestore(&gart->pte_lock, flags);
}
#else
static inline void gart_dump_table(struct gart_device *gart)
{
}
#endif
static inline bool gart_iova_range_valid(struct gart_device *gart,
unsigned long iova, size_t bytes)
{
unsigned long iova_start, iova_end, gart_start, gart_end;
iova_start = iova;
iova_end = iova_start + bytes - 1;
gart_start = gart->iovmm_base;
gart_end = gart_start + gart->page_count * GART_PAGE_SIZE - 1;
if (iova_start < gart_start)
return false;
if (iova_end > gart_end)
return false;
return true;
}
static int gart_iommu_attach_dev(struct iommu_domain *domain,
struct device *dev)
{
struct gart_device *gart;
struct gart_client *client, *c;
int err = 0;
gart = gart_handle;
if (!gart)
return -EINVAL;
domain->priv = gart;
client = devm_kzalloc(gart->dev, sizeof(*c), GFP_KERNEL);
if (!client)
return -ENOMEM;
client->dev = dev;
spin_lock(&gart->client_lock);
list_for_each_entry(c, &gart->client, list) {
if (c->dev == dev) {
dev_err(gart->dev,
"%s is already attached\n", dev_name(dev));
err = -EINVAL;
goto fail;
}
}
list_add(&client->list, &gart->client);
spin_unlock(&gart->client_lock);
dev_dbg(gart->dev, "Attached %s\n", dev_name(dev));
return 0;
fail:
devm_kfree(gart->dev, client);
spin_unlock(&gart->client_lock);
return err;
}
static void gart_iommu_detach_dev(struct iommu_domain *domain,
struct device *dev)
{
struct gart_device *gart = domain->priv;
struct gart_client *c;
spin_lock(&gart->client_lock);
list_for_each_entry(c, &gart->client, list) {
if (c->dev == dev) {
list_del(&c->list);
devm_kfree(gart->dev, c);
dev_dbg(gart->dev, "Detached %s\n", dev_name(dev));
goto out;
}
}
dev_err(gart->dev, "Couldn't find\n");
out:
spin_unlock(&gart->client_lock);
}
static int gart_iommu_domain_init(struct iommu_domain *domain)
{
return 0;
}
static void gart_iommu_domain_destroy(struct iommu_domain *domain)
{
struct gart_device *gart = domain->priv;
if (!gart)
return;
spin_lock(&gart->client_lock);
if (!list_empty(&gart->client)) {
struct gart_client *c;
list_for_each_entry(c, &gart->client, list)
gart_iommu_detach_dev(domain, c->dev);
}
spin_unlock(&gart->client_lock);
domain->priv = NULL;
}
static int gart_iommu_map(struct iommu_domain *domain, unsigned long iova,
phys_addr_t pa, size_t bytes, int prot)
{
struct gart_device *gart = domain->priv;
unsigned long flags;
unsigned long pfn;
if (!gart_iova_range_valid(gart, iova, bytes))
return -EINVAL;
spin_lock_irqsave(&gart->pte_lock, flags);
pfn = __phys_to_pfn(pa);
if (!pfn_valid(pfn)) {
dev_err(gart->dev, "Invalid page: %08x\n", pa);
spin_unlock_irqrestore(&gart->pte_lock, flags);
return -EINVAL;
}
gart_set_pte(gart, iova, GART_PTE(pfn));
FLUSH_GART_REGS(gart);
spin_unlock_irqrestore(&gart->pte_lock, flags);
return 0;
}
static size_t gart_iommu_unmap(struct iommu_domain *domain, unsigned long iova,
size_t bytes)
{
struct gart_device *gart = domain->priv;
unsigned long flags;
if (!gart_iova_range_valid(gart, iova, bytes))
return 0;
spin_lock_irqsave(&gart->pte_lock, flags);
gart_set_pte(gart, iova, 0);
FLUSH_GART_REGS(gart);
spin_unlock_irqrestore(&gart->pte_lock, flags);
return 0;
}
static phys_addr_t gart_iommu_iova_to_phys(struct iommu_domain *domain,
unsigned long iova)
{
struct gart_device *gart = domain->priv;
unsigned long pte;
phys_addr_t pa;
unsigned long flags;
if (!gart_iova_range_valid(gart, iova, 0))
return -EINVAL;
spin_lock_irqsave(&gart->pte_lock, flags);
pte = gart_read_pte(gart, iova);
spin_unlock_irqrestore(&gart->pte_lock, flags);
pa = (pte & GART_PAGE_MASK);
if (!pfn_valid(__phys_to_pfn(pa))) {
dev_err(gart->dev, "No entry for %08lx:%08x\n", iova, pa);
gart_dump_table(gart);
return -EINVAL;
}
return pa;
}
static int gart_iommu_domain_has_cap(struct iommu_domain *domain,
unsigned long cap)
{
return 0;
}
static struct iommu_ops gart_iommu_ops = {
.domain_init = gart_iommu_domain_init,
.domain_destroy = gart_iommu_domain_destroy,
.attach_dev = gart_iommu_attach_dev,
.detach_dev = gart_iommu_detach_dev,
.map = gart_iommu_map,
.unmap = gart_iommu_unmap,
.iova_to_phys = gart_iommu_iova_to_phys,
.domain_has_cap = gart_iommu_domain_has_cap,
.pgsize_bitmap = GART_IOMMU_PGSIZES,
};
static int tegra_gart_suspend(struct device *dev)
{
struct gart_device *gart = dev_get_drvdata(dev);
unsigned long iova;
u32 *data = gart->savedata;
unsigned long flags;
spin_lock_irqsave(&gart->pte_lock, flags);
for_each_gart_pte(gart, iova)
*(data++) = gart_read_pte(gart, iova);
spin_unlock_irqrestore(&gart->pte_lock, flags);
return 0;
}
static int tegra_gart_resume(struct device *dev)
{
struct gart_device *gart = dev_get_drvdata(dev);
unsigned long flags;
spin_lock_irqsave(&gart->pte_lock, flags);
do_gart_setup(gart, gart->savedata);
spin_unlock_irqrestore(&gart->pte_lock, flags);
return 0;
}
static int tegra_gart_probe(struct platform_device *pdev)
{
struct gart_device *gart;
struct resource *res, *res_remap;
void __iomem *gart_regs;
int err;
struct device *dev = &pdev->dev;
if (gart_handle)
return -EIO;
BUILD_BUG_ON(PAGE_SHIFT != GART_PAGE_SHIFT);
/* the GART memory aperture is required */
res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
res_remap = platform_get_resource(pdev, IORESOURCE_MEM, 1);
if (!res || !res_remap) {
dev_err(dev, "GART memory aperture expected\n");
return -ENXIO;
}
gart = devm_kzalloc(dev, sizeof(*gart), GFP_KERNEL);
if (!gart) {
dev_err(dev, "failed to allocate gart_device\n");
return -ENOMEM;
}
gart_regs = devm_ioremap(dev, res->start, resource_size(res));
if (!gart_regs) {
dev_err(dev, "failed to remap GART registers\n");
err = -ENXIO;
goto fail;
}
gart->dev = &pdev->dev;
spin_lock_init(&gart->pte_lock);
spin_lock_init(&gart->client_lock);
INIT_LIST_HEAD(&gart->client);
gart->regs = gart_regs;
gart->iovmm_base = (dma_addr_t)res_remap->start;
gart->page_count = (resource_size(res_remap) >> GART_PAGE_SHIFT);
gart->savedata = vmalloc(sizeof(u32) * gart->page_count);
if (!gart->savedata) {
dev_err(dev, "failed to allocate context save area\n");
err = -ENOMEM;
goto fail;
}
platform_set_drvdata(pdev, gart);
do_gart_setup(gart, NULL);
gart_handle = gart;
return 0;
fail:
if (gart_regs)
devm_iounmap(dev, gart_regs);
if (gart && gart->savedata)
vfree(gart->savedata);
devm_kfree(dev, gart);
return err;
}
static int tegra_gart_remove(struct platform_device *pdev)
{
struct gart_device *gart = platform_get_drvdata(pdev);
struct device *dev = gart->dev;
writel(0, gart->regs + GART_CONFIG);
if (gart->savedata)
vfree(gart->savedata);
if (gart->regs)
devm_iounmap(dev, gart->regs);
devm_kfree(dev, gart);
gart_handle = NULL;
return 0;
}
const struct dev_pm_ops tegra_gart_pm_ops = {
.suspend = tegra_gart_suspend,
.resume = tegra_gart_resume,
};
#ifdef CONFIG_OF
static struct of_device_id tegra_gart_of_match[] __devinitdata = {
{ .compatible = "nvidia,tegra20-gart", },
{ },
};
MODULE_DEVICE_TABLE(of, tegra_gart_of_match);
#endif
static struct platform_driver tegra_gart_driver = {
.probe = tegra_gart_probe,
.remove = tegra_gart_remove,
.driver = {
.owner = THIS_MODULE,
.name = "tegra-gart",
.pm = &tegra_gart_pm_ops,
.of_match_table = of_match_ptr(tegra_gart_of_match),
},
};
static int __devinit tegra_gart_init(void)
{
bus_set_iommu(&platform_bus_type, &gart_iommu_ops);
return platform_driver_register(&tegra_gart_driver);
}
static void __exit tegra_gart_exit(void)
{
platform_driver_unregister(&tegra_gart_driver);
}
subsys_initcall(tegra_gart_init);
module_exit(tegra_gart_exit);
MODULE_DESCRIPTION("IOMMU API for GART in Tegra20");
MODULE_AUTHOR("Hiroshi DOYU <hdoyu@nvidia.com>");
MODULE_ALIAS("platform:tegra-gart");
MODULE_LICENSE("GPL v2");