linux/drivers/iommu/sun50i-iommu.c
Niklas Schnelle fa4c450709 iommu: Allow .iotlb_sync_map to fail and handle s390's -ENOMEM return
On s390 when using a paging hypervisor, .iotlb_sync_map is used to sync
mappings by letting the hypervisor inspect the synced IOVA range and
updating a shadow table. This however means that .iotlb_sync_map can
fail as the hypervisor may run out of resources while doing the sync.
This can be due to the hypervisor being unable to pin guest pages, due
to a limit on mapped addresses such as vfio_iommu_type1.dma_entry_limit
or lack of other resources. Either way such a failure to sync a mapping
should result in a DMA_MAPPING_ERROR.

Now especially when running with batched IOTLB flushes for unmap it may
be that some IOVAs have already been invalidated but not yet synced via
.iotlb_sync_map. Thus if the hypervisor indicates running out of
resources, first do a global flush allowing the hypervisor to free
resources associated with these mappings as well a retry creating the
new mappings and only if that also fails report this error to callers.

Reviewed-by: Lu Baolu <baolu.lu@linux.intel.com>
Reviewed-by: Matthew Rosato <mjrosato@linux.ibm.com>
Acked-by: Jernej Skrabec <jernej.skrabec@gmail.com> # sun50i
Signed-off-by: Niklas Schnelle <schnelle@linux.ibm.com>
Link: https://lore.kernel.org/r/20230928-dma_iommu-v13-1-9e5fc4dacc36@linux.ibm.com
Signed-off-by: Joerg Roedel <jroedel@suse.de>
2023-10-02 08:42:57 +02:00

1075 lines
29 KiB
C

// SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
// Copyright (C) 2016-2018, Allwinner Technology CO., LTD.
// Copyright (C) 2019-2020, Cerno
#include <linux/bitfield.h>
#include <linux/bug.h>
#include <linux/clk.h>
#include <linux/device.h>
#include <linux/dma-direction.h>
#include <linux/dma-mapping.h>
#include <linux/err.h>
#include <linux/errno.h>
#include <linux/interrupt.h>
#include <linux/iommu.h>
#include <linux/iopoll.h>
#include <linux/ioport.h>
#include <linux/log2.h>
#include <linux/module.h>
#include <linux/of_platform.h>
#include <linux/platform_device.h>
#include <linux/pm.h>
#include <linux/pm_runtime.h>
#include <linux/reset.h>
#include <linux/sizes.h>
#include <linux/slab.h>
#include <linux/spinlock.h>
#include <linux/types.h>
#define IOMMU_RESET_REG 0x010
#define IOMMU_RESET_RELEASE_ALL 0xffffffff
#define IOMMU_ENABLE_REG 0x020
#define IOMMU_ENABLE_ENABLE BIT(0)
#define IOMMU_BYPASS_REG 0x030
#define IOMMU_AUTO_GATING_REG 0x040
#define IOMMU_AUTO_GATING_ENABLE BIT(0)
#define IOMMU_WBUF_CTRL_REG 0x044
#define IOMMU_OOO_CTRL_REG 0x048
#define IOMMU_4KB_BDY_PRT_CTRL_REG 0x04c
#define IOMMU_TTB_REG 0x050
#define IOMMU_TLB_ENABLE_REG 0x060
#define IOMMU_TLB_PREFETCH_REG 0x070
#define IOMMU_TLB_PREFETCH_MASTER_ENABLE(m) BIT(m)
#define IOMMU_TLB_FLUSH_REG 0x080
#define IOMMU_TLB_FLUSH_PTW_CACHE BIT(17)
#define IOMMU_TLB_FLUSH_MACRO_TLB BIT(16)
#define IOMMU_TLB_FLUSH_MICRO_TLB(i) (BIT(i) & GENMASK(5, 0))
#define IOMMU_TLB_IVLD_ADDR_REG 0x090
#define IOMMU_TLB_IVLD_ADDR_MASK_REG 0x094
#define IOMMU_TLB_IVLD_ENABLE_REG 0x098
#define IOMMU_TLB_IVLD_ENABLE_ENABLE BIT(0)
#define IOMMU_PC_IVLD_ADDR_REG 0x0a0
#define IOMMU_PC_IVLD_ENABLE_REG 0x0a8
#define IOMMU_PC_IVLD_ENABLE_ENABLE BIT(0)
#define IOMMU_DM_AUT_CTRL_REG(d) (0x0b0 + ((d) / 2) * 4)
#define IOMMU_DM_AUT_CTRL_RD_UNAVAIL(d, m) (1 << (((d & 1) * 16) + ((m) * 2)))
#define IOMMU_DM_AUT_CTRL_WR_UNAVAIL(d, m) (1 << (((d & 1) * 16) + ((m) * 2) + 1))
#define IOMMU_DM_AUT_OVWT_REG 0x0d0
#define IOMMU_INT_ENABLE_REG 0x100
#define IOMMU_INT_CLR_REG 0x104
#define IOMMU_INT_STA_REG 0x108
#define IOMMU_INT_ERR_ADDR_REG(i) (0x110 + (i) * 4)
#define IOMMU_INT_ERR_ADDR_L1_REG 0x130
#define IOMMU_INT_ERR_ADDR_L2_REG 0x134
#define IOMMU_INT_ERR_DATA_REG(i) (0x150 + (i) * 4)
#define IOMMU_L1PG_INT_REG 0x0180
#define IOMMU_L2PG_INT_REG 0x0184
#define IOMMU_INT_INVALID_L2PG BIT(17)
#define IOMMU_INT_INVALID_L1PG BIT(16)
#define IOMMU_INT_MASTER_PERMISSION(m) BIT(m)
#define IOMMU_INT_MASTER_MASK (IOMMU_INT_MASTER_PERMISSION(0) | \
IOMMU_INT_MASTER_PERMISSION(1) | \
IOMMU_INT_MASTER_PERMISSION(2) | \
IOMMU_INT_MASTER_PERMISSION(3) | \
IOMMU_INT_MASTER_PERMISSION(4) | \
IOMMU_INT_MASTER_PERMISSION(5))
#define IOMMU_INT_MASK (IOMMU_INT_INVALID_L1PG | \
IOMMU_INT_INVALID_L2PG | \
IOMMU_INT_MASTER_MASK)
#define PT_ENTRY_SIZE sizeof(u32)
#define NUM_DT_ENTRIES 4096
#define DT_SIZE (NUM_DT_ENTRIES * PT_ENTRY_SIZE)
#define NUM_PT_ENTRIES 256
#define PT_SIZE (NUM_PT_ENTRIES * PT_ENTRY_SIZE)
#define SPAGE_SIZE 4096
struct sun50i_iommu {
struct iommu_device iommu;
/* Lock to modify the IOMMU registers */
spinlock_t iommu_lock;
struct device *dev;
void __iomem *base;
struct reset_control *reset;
struct clk *clk;
struct iommu_domain *domain;
struct kmem_cache *pt_pool;
};
struct sun50i_iommu_domain {
struct iommu_domain domain;
/* Number of devices attached to the domain */
refcount_t refcnt;
/* L1 Page Table */
u32 *dt;
dma_addr_t dt_dma;
struct sun50i_iommu *iommu;
};
static struct sun50i_iommu_domain *to_sun50i_domain(struct iommu_domain *domain)
{
return container_of(domain, struct sun50i_iommu_domain, domain);
}
static struct sun50i_iommu *sun50i_iommu_from_dev(struct device *dev)
{
return dev_iommu_priv_get(dev);
}
static u32 iommu_read(struct sun50i_iommu *iommu, u32 offset)
{
return readl(iommu->base + offset);
}
static void iommu_write(struct sun50i_iommu *iommu, u32 offset, u32 value)
{
writel(value, iommu->base + offset);
}
/*
* The Allwinner H6 IOMMU uses a 2-level page table.
*
* The first level is the usual Directory Table (DT), that consists of
* 4096 4-bytes Directory Table Entries (DTE), each pointing to a Page
* Table (PT).
*
* Each PT consits of 256 4-bytes Page Table Entries (PTE), each
* pointing to a 4kB page of physical memory.
*
* The IOMMU supports a single DT, pointed by the IOMMU_TTB_REG
* register that contains its physical address.
*/
#define SUN50I_IOVA_DTE_MASK GENMASK(31, 20)
#define SUN50I_IOVA_PTE_MASK GENMASK(19, 12)
#define SUN50I_IOVA_PAGE_MASK GENMASK(11, 0)
static u32 sun50i_iova_get_dte_index(dma_addr_t iova)
{
return FIELD_GET(SUN50I_IOVA_DTE_MASK, iova);
}
static u32 sun50i_iova_get_pte_index(dma_addr_t iova)
{
return FIELD_GET(SUN50I_IOVA_PTE_MASK, iova);
}
static u32 sun50i_iova_get_page_offset(dma_addr_t iova)
{
return FIELD_GET(SUN50I_IOVA_PAGE_MASK, iova);
}
/*
* Each Directory Table Entry has a Page Table address and a valid
* bit:
* +---------------------+-----------+-+
* | PT address | Reserved |V|
* +---------------------+-----------+-+
* 31:10 - Page Table address
* 9:2 - Reserved
* 1:0 - 1 if the entry is valid
*/
#define SUN50I_DTE_PT_ADDRESS_MASK GENMASK(31, 10)
#define SUN50I_DTE_PT_ATTRS GENMASK(1, 0)
#define SUN50I_DTE_PT_VALID 1
static phys_addr_t sun50i_dte_get_pt_address(u32 dte)
{
return (phys_addr_t)dte & SUN50I_DTE_PT_ADDRESS_MASK;
}
static bool sun50i_dte_is_pt_valid(u32 dte)
{
return (dte & SUN50I_DTE_PT_ATTRS) == SUN50I_DTE_PT_VALID;
}
static u32 sun50i_mk_dte(dma_addr_t pt_dma)
{
return (pt_dma & SUN50I_DTE_PT_ADDRESS_MASK) | SUN50I_DTE_PT_VALID;
}
/*
* Each PTE has a Page address, an authority index and a valid bit:
*
* +----------------+-----+-----+-----+---+-----+
* | Page address | Rsv | ACI | Rsv | V | Rsv |
* +----------------+-----+-----+-----+---+-----+
* 31:12 - Page address
* 11:8 - Reserved
* 7:4 - Authority Control Index
* 3:2 - Reserved
* 1 - 1 if the entry is valid
* 0 - Reserved
*
* The way permissions work is that the IOMMU has 16 "domains" that
* can be configured to give each masters either read or write
* permissions through the IOMMU_DM_AUT_CTRL_REG registers. The domain
* 0 seems like the default domain, and its permissions in the
* IOMMU_DM_AUT_CTRL_REG are only read-only, so it's not really
* useful to enforce any particular permission.
*
* Each page entry will then have a reference to the domain they are
* affected to, so that we can actually enforce them on a per-page
* basis.
*
* In order to make it work with the IOMMU framework, we will be using
* 4 different domains, starting at 1: RD_WR, RD, WR and NONE
* depending on the permission we want to enforce. Each domain will
* have each master setup in the same way, since the IOMMU framework
* doesn't seem to restrict page access on a per-device basis. And
* then we will use the relevant domain index when generating the page
* table entry depending on the permissions we want to be enforced.
*/
enum sun50i_iommu_aci {
SUN50I_IOMMU_ACI_DO_NOT_USE = 0,
SUN50I_IOMMU_ACI_NONE,
SUN50I_IOMMU_ACI_RD,
SUN50I_IOMMU_ACI_WR,
SUN50I_IOMMU_ACI_RD_WR,
};
#define SUN50I_PTE_PAGE_ADDRESS_MASK GENMASK(31, 12)
#define SUN50I_PTE_ACI_MASK GENMASK(7, 4)
#define SUN50I_PTE_PAGE_VALID BIT(1)
static phys_addr_t sun50i_pte_get_page_address(u32 pte)
{
return (phys_addr_t)pte & SUN50I_PTE_PAGE_ADDRESS_MASK;
}
static enum sun50i_iommu_aci sun50i_get_pte_aci(u32 pte)
{
return FIELD_GET(SUN50I_PTE_ACI_MASK, pte);
}
static bool sun50i_pte_is_page_valid(u32 pte)
{
return pte & SUN50I_PTE_PAGE_VALID;
}
static u32 sun50i_mk_pte(phys_addr_t page, int prot)
{
enum sun50i_iommu_aci aci;
u32 flags = 0;
if ((prot & (IOMMU_READ | IOMMU_WRITE)) == (IOMMU_READ | IOMMU_WRITE))
aci = SUN50I_IOMMU_ACI_RD_WR;
else if (prot & IOMMU_READ)
aci = SUN50I_IOMMU_ACI_RD;
else if (prot & IOMMU_WRITE)
aci = SUN50I_IOMMU_ACI_WR;
else
aci = SUN50I_IOMMU_ACI_NONE;
flags |= FIELD_PREP(SUN50I_PTE_ACI_MASK, aci);
page &= SUN50I_PTE_PAGE_ADDRESS_MASK;
return page | flags | SUN50I_PTE_PAGE_VALID;
}
static void sun50i_table_flush(struct sun50i_iommu_domain *sun50i_domain,
void *vaddr, unsigned int count)
{
struct sun50i_iommu *iommu = sun50i_domain->iommu;
dma_addr_t dma = virt_to_phys(vaddr);
size_t size = count * PT_ENTRY_SIZE;
dma_sync_single_for_device(iommu->dev, dma, size, DMA_TO_DEVICE);
}
static void sun50i_iommu_zap_iova(struct sun50i_iommu *iommu,
unsigned long iova)
{
u32 reg;
int ret;
iommu_write(iommu, IOMMU_TLB_IVLD_ADDR_REG, iova);
iommu_write(iommu, IOMMU_TLB_IVLD_ADDR_MASK_REG, GENMASK(31, 12));
iommu_write(iommu, IOMMU_TLB_IVLD_ENABLE_REG,
IOMMU_TLB_IVLD_ENABLE_ENABLE);
ret = readl_poll_timeout_atomic(iommu->base + IOMMU_TLB_IVLD_ENABLE_REG,
reg, !reg, 1, 2000);
if (ret)
dev_warn(iommu->dev, "TLB invalidation timed out!\n");
}
static void sun50i_iommu_zap_ptw_cache(struct sun50i_iommu *iommu,
unsigned long iova)
{
u32 reg;
int ret;
iommu_write(iommu, IOMMU_PC_IVLD_ADDR_REG, iova);
iommu_write(iommu, IOMMU_PC_IVLD_ENABLE_REG,
IOMMU_PC_IVLD_ENABLE_ENABLE);
ret = readl_poll_timeout_atomic(iommu->base + IOMMU_PC_IVLD_ENABLE_REG,
reg, !reg, 1, 2000);
if (ret)
dev_warn(iommu->dev, "PTW cache invalidation timed out!\n");
}
static void sun50i_iommu_zap_range(struct sun50i_iommu *iommu,
unsigned long iova, size_t size)
{
assert_spin_locked(&iommu->iommu_lock);
iommu_write(iommu, IOMMU_AUTO_GATING_REG, 0);
sun50i_iommu_zap_iova(iommu, iova);
sun50i_iommu_zap_iova(iommu, iova + SPAGE_SIZE);
if (size > SPAGE_SIZE) {
sun50i_iommu_zap_iova(iommu, iova + size);
sun50i_iommu_zap_iova(iommu, iova + size + SPAGE_SIZE);
}
sun50i_iommu_zap_ptw_cache(iommu, iova);
sun50i_iommu_zap_ptw_cache(iommu, iova + SZ_1M);
if (size > SZ_1M) {
sun50i_iommu_zap_ptw_cache(iommu, iova + size);
sun50i_iommu_zap_ptw_cache(iommu, iova + size + SZ_1M);
}
iommu_write(iommu, IOMMU_AUTO_GATING_REG, IOMMU_AUTO_GATING_ENABLE);
}
static int sun50i_iommu_flush_all_tlb(struct sun50i_iommu *iommu)
{
u32 reg;
int ret;
assert_spin_locked(&iommu->iommu_lock);
iommu_write(iommu,
IOMMU_TLB_FLUSH_REG,
IOMMU_TLB_FLUSH_PTW_CACHE |
IOMMU_TLB_FLUSH_MACRO_TLB |
IOMMU_TLB_FLUSH_MICRO_TLB(5) |
IOMMU_TLB_FLUSH_MICRO_TLB(4) |
IOMMU_TLB_FLUSH_MICRO_TLB(3) |
IOMMU_TLB_FLUSH_MICRO_TLB(2) |
IOMMU_TLB_FLUSH_MICRO_TLB(1) |
IOMMU_TLB_FLUSH_MICRO_TLB(0));
ret = readl_poll_timeout_atomic(iommu->base + IOMMU_TLB_FLUSH_REG,
reg, !reg,
1, 2000);
if (ret)
dev_warn(iommu->dev, "TLB Flush timed out!\n");
return ret;
}
static void sun50i_iommu_flush_iotlb_all(struct iommu_domain *domain)
{
struct sun50i_iommu_domain *sun50i_domain = to_sun50i_domain(domain);
struct sun50i_iommu *iommu = sun50i_domain->iommu;
unsigned long flags;
/*
* At boot, we'll have a first call into .flush_iotlb_all right after
* .probe_device, and since we link our (single) domain to our iommu in
* the .attach_device callback, we don't have that pointer set.
*
* It shouldn't really be any trouble to ignore it though since we flush
* all caches as part of the device powerup.
*/
if (!iommu)
return;
spin_lock_irqsave(&iommu->iommu_lock, flags);
sun50i_iommu_flush_all_tlb(iommu);
spin_unlock_irqrestore(&iommu->iommu_lock, flags);
}
static int sun50i_iommu_iotlb_sync_map(struct iommu_domain *domain,
unsigned long iova, size_t size)
{
struct sun50i_iommu_domain *sun50i_domain = to_sun50i_domain(domain);
struct sun50i_iommu *iommu = sun50i_domain->iommu;
unsigned long flags;
spin_lock_irqsave(&iommu->iommu_lock, flags);
sun50i_iommu_zap_range(iommu, iova, size);
spin_unlock_irqrestore(&iommu->iommu_lock, flags);
return 0;
}
static void sun50i_iommu_iotlb_sync(struct iommu_domain *domain,
struct iommu_iotlb_gather *gather)
{
sun50i_iommu_flush_iotlb_all(domain);
}
static int sun50i_iommu_enable(struct sun50i_iommu *iommu)
{
struct sun50i_iommu_domain *sun50i_domain;
unsigned long flags;
int ret;
if (!iommu->domain)
return 0;
sun50i_domain = to_sun50i_domain(iommu->domain);
ret = reset_control_deassert(iommu->reset);
if (ret)
return ret;
ret = clk_prepare_enable(iommu->clk);
if (ret)
goto err_reset_assert;
spin_lock_irqsave(&iommu->iommu_lock, flags);
iommu_write(iommu, IOMMU_TTB_REG, sun50i_domain->dt_dma);
iommu_write(iommu, IOMMU_TLB_PREFETCH_REG,
IOMMU_TLB_PREFETCH_MASTER_ENABLE(0) |
IOMMU_TLB_PREFETCH_MASTER_ENABLE(1) |
IOMMU_TLB_PREFETCH_MASTER_ENABLE(2) |
IOMMU_TLB_PREFETCH_MASTER_ENABLE(3) |
IOMMU_TLB_PREFETCH_MASTER_ENABLE(4) |
IOMMU_TLB_PREFETCH_MASTER_ENABLE(5));
iommu_write(iommu, IOMMU_INT_ENABLE_REG, IOMMU_INT_MASK);
iommu_write(iommu, IOMMU_DM_AUT_CTRL_REG(SUN50I_IOMMU_ACI_NONE),
IOMMU_DM_AUT_CTRL_RD_UNAVAIL(SUN50I_IOMMU_ACI_NONE, 0) |
IOMMU_DM_AUT_CTRL_WR_UNAVAIL(SUN50I_IOMMU_ACI_NONE, 0) |
IOMMU_DM_AUT_CTRL_RD_UNAVAIL(SUN50I_IOMMU_ACI_NONE, 1) |
IOMMU_DM_AUT_CTRL_WR_UNAVAIL(SUN50I_IOMMU_ACI_NONE, 1) |
IOMMU_DM_AUT_CTRL_RD_UNAVAIL(SUN50I_IOMMU_ACI_NONE, 2) |
IOMMU_DM_AUT_CTRL_WR_UNAVAIL(SUN50I_IOMMU_ACI_NONE, 2) |
IOMMU_DM_AUT_CTRL_RD_UNAVAIL(SUN50I_IOMMU_ACI_NONE, 3) |
IOMMU_DM_AUT_CTRL_WR_UNAVAIL(SUN50I_IOMMU_ACI_NONE, 3) |
IOMMU_DM_AUT_CTRL_RD_UNAVAIL(SUN50I_IOMMU_ACI_NONE, 4) |
IOMMU_DM_AUT_CTRL_WR_UNAVAIL(SUN50I_IOMMU_ACI_NONE, 4) |
IOMMU_DM_AUT_CTRL_RD_UNAVAIL(SUN50I_IOMMU_ACI_NONE, 5) |
IOMMU_DM_AUT_CTRL_WR_UNAVAIL(SUN50I_IOMMU_ACI_NONE, 5));
iommu_write(iommu, IOMMU_DM_AUT_CTRL_REG(SUN50I_IOMMU_ACI_RD),
IOMMU_DM_AUT_CTRL_WR_UNAVAIL(SUN50I_IOMMU_ACI_RD, 0) |
IOMMU_DM_AUT_CTRL_WR_UNAVAIL(SUN50I_IOMMU_ACI_RD, 1) |
IOMMU_DM_AUT_CTRL_WR_UNAVAIL(SUN50I_IOMMU_ACI_RD, 2) |
IOMMU_DM_AUT_CTRL_WR_UNAVAIL(SUN50I_IOMMU_ACI_RD, 3) |
IOMMU_DM_AUT_CTRL_WR_UNAVAIL(SUN50I_IOMMU_ACI_RD, 4) |
IOMMU_DM_AUT_CTRL_WR_UNAVAIL(SUN50I_IOMMU_ACI_RD, 5));
iommu_write(iommu, IOMMU_DM_AUT_CTRL_REG(SUN50I_IOMMU_ACI_WR),
IOMMU_DM_AUT_CTRL_RD_UNAVAIL(SUN50I_IOMMU_ACI_WR, 0) |
IOMMU_DM_AUT_CTRL_RD_UNAVAIL(SUN50I_IOMMU_ACI_WR, 1) |
IOMMU_DM_AUT_CTRL_RD_UNAVAIL(SUN50I_IOMMU_ACI_WR, 2) |
IOMMU_DM_AUT_CTRL_RD_UNAVAIL(SUN50I_IOMMU_ACI_WR, 3) |
IOMMU_DM_AUT_CTRL_RD_UNAVAIL(SUN50I_IOMMU_ACI_WR, 4) |
IOMMU_DM_AUT_CTRL_RD_UNAVAIL(SUN50I_IOMMU_ACI_WR, 5));
ret = sun50i_iommu_flush_all_tlb(iommu);
if (ret) {
spin_unlock_irqrestore(&iommu->iommu_lock, flags);
goto err_clk_disable;
}
iommu_write(iommu, IOMMU_AUTO_GATING_REG, IOMMU_AUTO_GATING_ENABLE);
iommu_write(iommu, IOMMU_ENABLE_REG, IOMMU_ENABLE_ENABLE);
spin_unlock_irqrestore(&iommu->iommu_lock, flags);
return 0;
err_clk_disable:
clk_disable_unprepare(iommu->clk);
err_reset_assert:
reset_control_assert(iommu->reset);
return ret;
}
static void sun50i_iommu_disable(struct sun50i_iommu *iommu)
{
unsigned long flags;
spin_lock_irqsave(&iommu->iommu_lock, flags);
iommu_write(iommu, IOMMU_ENABLE_REG, 0);
iommu_write(iommu, IOMMU_TTB_REG, 0);
spin_unlock_irqrestore(&iommu->iommu_lock, flags);
clk_disable_unprepare(iommu->clk);
reset_control_assert(iommu->reset);
}
static void *sun50i_iommu_alloc_page_table(struct sun50i_iommu *iommu,
gfp_t gfp)
{
dma_addr_t pt_dma;
u32 *page_table;
page_table = kmem_cache_zalloc(iommu->pt_pool, gfp);
if (!page_table)
return ERR_PTR(-ENOMEM);
pt_dma = dma_map_single(iommu->dev, page_table, PT_SIZE, DMA_TO_DEVICE);
if (dma_mapping_error(iommu->dev, pt_dma)) {
dev_err(iommu->dev, "Couldn't map L2 Page Table\n");
kmem_cache_free(iommu->pt_pool, page_table);
return ERR_PTR(-ENOMEM);
}
/* We rely on the physical address and DMA address being the same */
WARN_ON(pt_dma != virt_to_phys(page_table));
return page_table;
}
static void sun50i_iommu_free_page_table(struct sun50i_iommu *iommu,
u32 *page_table)
{
phys_addr_t pt_phys = virt_to_phys(page_table);
dma_unmap_single(iommu->dev, pt_phys, PT_SIZE, DMA_TO_DEVICE);
kmem_cache_free(iommu->pt_pool, page_table);
}
static u32 *sun50i_dte_get_page_table(struct sun50i_iommu_domain *sun50i_domain,
dma_addr_t iova, gfp_t gfp)
{
struct sun50i_iommu *iommu = sun50i_domain->iommu;
u32 *page_table;
u32 *dte_addr;
u32 old_dte;
u32 dte;
dte_addr = &sun50i_domain->dt[sun50i_iova_get_dte_index(iova)];
dte = *dte_addr;
if (sun50i_dte_is_pt_valid(dte)) {
phys_addr_t pt_phys = sun50i_dte_get_pt_address(dte);
return (u32 *)phys_to_virt(pt_phys);
}
page_table = sun50i_iommu_alloc_page_table(iommu, gfp);
if (IS_ERR(page_table))
return page_table;
dte = sun50i_mk_dte(virt_to_phys(page_table));
old_dte = cmpxchg(dte_addr, 0, dte);
if (old_dte) {
phys_addr_t installed_pt_phys =
sun50i_dte_get_pt_address(old_dte);
u32 *installed_pt = phys_to_virt(installed_pt_phys);
u32 *drop_pt = page_table;
page_table = installed_pt;
dte = old_dte;
sun50i_iommu_free_page_table(iommu, drop_pt);
}
sun50i_table_flush(sun50i_domain, page_table, NUM_PT_ENTRIES);
sun50i_table_flush(sun50i_domain, dte_addr, 1);
return page_table;
}
static int sun50i_iommu_map(struct iommu_domain *domain, unsigned long iova,
phys_addr_t paddr, size_t size, size_t count,
int prot, gfp_t gfp, size_t *mapped)
{
struct sun50i_iommu_domain *sun50i_domain = to_sun50i_domain(domain);
struct sun50i_iommu *iommu = sun50i_domain->iommu;
u32 pte_index;
u32 *page_table, *pte_addr;
int ret = 0;
page_table = sun50i_dte_get_page_table(sun50i_domain, iova, gfp);
if (IS_ERR(page_table)) {
ret = PTR_ERR(page_table);
goto out;
}
pte_index = sun50i_iova_get_pte_index(iova);
pte_addr = &page_table[pte_index];
if (unlikely(sun50i_pte_is_page_valid(*pte_addr))) {
phys_addr_t page_phys = sun50i_pte_get_page_address(*pte_addr);
dev_err(iommu->dev,
"iova %pad already mapped to %pa cannot remap to %pa prot: %#x\n",
&iova, &page_phys, &paddr, prot);
ret = -EBUSY;
goto out;
}
*pte_addr = sun50i_mk_pte(paddr, prot);
sun50i_table_flush(sun50i_domain, pte_addr, 1);
*mapped = size;
out:
return ret;
}
static size_t sun50i_iommu_unmap(struct iommu_domain *domain, unsigned long iova,
size_t size, size_t count, struct iommu_iotlb_gather *gather)
{
struct sun50i_iommu_domain *sun50i_domain = to_sun50i_domain(domain);
phys_addr_t pt_phys;
u32 *pte_addr;
u32 dte;
dte = sun50i_domain->dt[sun50i_iova_get_dte_index(iova)];
if (!sun50i_dte_is_pt_valid(dte))
return 0;
pt_phys = sun50i_dte_get_pt_address(dte);
pte_addr = (u32 *)phys_to_virt(pt_phys) + sun50i_iova_get_pte_index(iova);
if (!sun50i_pte_is_page_valid(*pte_addr))
return 0;
memset(pte_addr, 0, sizeof(*pte_addr));
sun50i_table_flush(sun50i_domain, pte_addr, 1);
return SZ_4K;
}
static phys_addr_t sun50i_iommu_iova_to_phys(struct iommu_domain *domain,
dma_addr_t iova)
{
struct sun50i_iommu_domain *sun50i_domain = to_sun50i_domain(domain);
phys_addr_t pt_phys;
u32 *page_table;
u32 dte, pte;
dte = sun50i_domain->dt[sun50i_iova_get_dte_index(iova)];
if (!sun50i_dte_is_pt_valid(dte))
return 0;
pt_phys = sun50i_dte_get_pt_address(dte);
page_table = (u32 *)phys_to_virt(pt_phys);
pte = page_table[sun50i_iova_get_pte_index(iova)];
if (!sun50i_pte_is_page_valid(pte))
return 0;
return sun50i_pte_get_page_address(pte) +
sun50i_iova_get_page_offset(iova);
}
static struct iommu_domain *
sun50i_iommu_domain_alloc_paging(struct device *dev)
{
struct sun50i_iommu_domain *sun50i_domain;
sun50i_domain = kzalloc(sizeof(*sun50i_domain), GFP_KERNEL);
if (!sun50i_domain)
return NULL;
sun50i_domain->dt = (u32 *)__get_free_pages(GFP_KERNEL | __GFP_ZERO,
get_order(DT_SIZE));
if (!sun50i_domain->dt)
goto err_free_domain;
refcount_set(&sun50i_domain->refcnt, 1);
sun50i_domain->domain.geometry.aperture_start = 0;
sun50i_domain->domain.geometry.aperture_end = DMA_BIT_MASK(32);
sun50i_domain->domain.geometry.force_aperture = true;
return &sun50i_domain->domain;
err_free_domain:
kfree(sun50i_domain);
return NULL;
}
static void sun50i_iommu_domain_free(struct iommu_domain *domain)
{
struct sun50i_iommu_domain *sun50i_domain = to_sun50i_domain(domain);
free_pages((unsigned long)sun50i_domain->dt, get_order(DT_SIZE));
sun50i_domain->dt = NULL;
kfree(sun50i_domain);
}
static int sun50i_iommu_attach_domain(struct sun50i_iommu *iommu,
struct sun50i_iommu_domain *sun50i_domain)
{
iommu->domain = &sun50i_domain->domain;
sun50i_domain->iommu = iommu;
sun50i_domain->dt_dma = dma_map_single(iommu->dev, sun50i_domain->dt,
DT_SIZE, DMA_TO_DEVICE);
if (dma_mapping_error(iommu->dev, sun50i_domain->dt_dma)) {
dev_err(iommu->dev, "Couldn't map L1 Page Table\n");
return -ENOMEM;
}
return sun50i_iommu_enable(iommu);
}
static void sun50i_iommu_detach_domain(struct sun50i_iommu *iommu,
struct sun50i_iommu_domain *sun50i_domain)
{
unsigned int i;
for (i = 0; i < NUM_DT_ENTRIES; i++) {
phys_addr_t pt_phys;
u32 *page_table;
u32 *dte_addr;
u32 dte;
dte_addr = &sun50i_domain->dt[i];
dte = *dte_addr;
if (!sun50i_dte_is_pt_valid(dte))
continue;
memset(dte_addr, 0, sizeof(*dte_addr));
sun50i_table_flush(sun50i_domain, dte_addr, 1);
pt_phys = sun50i_dte_get_pt_address(dte);
page_table = phys_to_virt(pt_phys);
sun50i_iommu_free_page_table(iommu, page_table);
}
sun50i_iommu_disable(iommu);
dma_unmap_single(iommu->dev, virt_to_phys(sun50i_domain->dt),
DT_SIZE, DMA_TO_DEVICE);
iommu->domain = NULL;
}
static int sun50i_iommu_identity_attach(struct iommu_domain *identity_domain,
struct device *dev)
{
struct sun50i_iommu *iommu = dev_iommu_priv_get(dev);
struct sun50i_iommu_domain *sun50i_domain;
dev_dbg(dev, "Detaching from IOMMU domain\n");
if (iommu->domain == identity_domain)
return 0;
sun50i_domain = to_sun50i_domain(iommu->domain);
if (refcount_dec_and_test(&sun50i_domain->refcnt))
sun50i_iommu_detach_domain(iommu, sun50i_domain);
return 0;
}
static struct iommu_domain_ops sun50i_iommu_identity_ops = {
.attach_dev = sun50i_iommu_identity_attach,
};
static struct iommu_domain sun50i_iommu_identity_domain = {
.type = IOMMU_DOMAIN_IDENTITY,
.ops = &sun50i_iommu_identity_ops,
};
static int sun50i_iommu_attach_device(struct iommu_domain *domain,
struct device *dev)
{
struct sun50i_iommu_domain *sun50i_domain = to_sun50i_domain(domain);
struct sun50i_iommu *iommu;
iommu = sun50i_iommu_from_dev(dev);
if (!iommu)
return -ENODEV;
dev_dbg(dev, "Attaching to IOMMU domain\n");
refcount_inc(&sun50i_domain->refcnt);
if (iommu->domain == domain)
return 0;
sun50i_iommu_identity_attach(&sun50i_iommu_identity_domain, dev);
sun50i_iommu_attach_domain(iommu, sun50i_domain);
return 0;
}
static struct iommu_device *sun50i_iommu_probe_device(struct device *dev)
{
struct sun50i_iommu *iommu;
iommu = sun50i_iommu_from_dev(dev);
if (!iommu)
return ERR_PTR(-ENODEV);
return &iommu->iommu;
}
static int sun50i_iommu_of_xlate(struct device *dev,
struct of_phandle_args *args)
{
struct platform_device *iommu_pdev = of_find_device_by_node(args->np);
unsigned id = args->args[0];
dev_iommu_priv_set(dev, platform_get_drvdata(iommu_pdev));
return iommu_fwspec_add_ids(dev, &id, 1);
}
static const struct iommu_ops sun50i_iommu_ops = {
.identity_domain = &sun50i_iommu_identity_domain,
.pgsize_bitmap = SZ_4K,
.device_group = generic_single_device_group,
.domain_alloc_paging = sun50i_iommu_domain_alloc_paging,
.of_xlate = sun50i_iommu_of_xlate,
.probe_device = sun50i_iommu_probe_device,
.default_domain_ops = &(const struct iommu_domain_ops) {
.attach_dev = sun50i_iommu_attach_device,
.flush_iotlb_all = sun50i_iommu_flush_iotlb_all,
.iotlb_sync_map = sun50i_iommu_iotlb_sync_map,
.iotlb_sync = sun50i_iommu_iotlb_sync,
.iova_to_phys = sun50i_iommu_iova_to_phys,
.map_pages = sun50i_iommu_map,
.unmap_pages = sun50i_iommu_unmap,
.free = sun50i_iommu_domain_free,
}
};
static void sun50i_iommu_report_fault(struct sun50i_iommu *iommu,
unsigned master, phys_addr_t iova,
unsigned prot)
{
dev_err(iommu->dev, "Page fault for %pad (master %d, dir %s)\n",
&iova, master, (prot == IOMMU_FAULT_WRITE) ? "wr" : "rd");
if (iommu->domain)
report_iommu_fault(iommu->domain, iommu->dev, iova, prot);
else
dev_err(iommu->dev, "Page fault while iommu not attached to any domain?\n");
sun50i_iommu_zap_range(iommu, iova, SPAGE_SIZE);
}
static phys_addr_t sun50i_iommu_handle_pt_irq(struct sun50i_iommu *iommu,
unsigned addr_reg,
unsigned blame_reg)
{
phys_addr_t iova;
unsigned master;
u32 blame;
assert_spin_locked(&iommu->iommu_lock);
iova = iommu_read(iommu, addr_reg);
blame = iommu_read(iommu, blame_reg);
master = ilog2(blame & IOMMU_INT_MASTER_MASK);
/*
* If the address is not in the page table, we can't get what
* operation triggered the fault. Assume it's a read
* operation.
*/
sun50i_iommu_report_fault(iommu, master, iova, IOMMU_FAULT_READ);
return iova;
}
static phys_addr_t sun50i_iommu_handle_perm_irq(struct sun50i_iommu *iommu)
{
enum sun50i_iommu_aci aci;
phys_addr_t iova;
unsigned master;
unsigned dir;
u32 blame;
assert_spin_locked(&iommu->iommu_lock);
blame = iommu_read(iommu, IOMMU_INT_STA_REG);
master = ilog2(blame & IOMMU_INT_MASTER_MASK);
iova = iommu_read(iommu, IOMMU_INT_ERR_ADDR_REG(master));
aci = sun50i_get_pte_aci(iommu_read(iommu,
IOMMU_INT_ERR_DATA_REG(master)));
switch (aci) {
/*
* If we are in the read-only domain, then it means we
* tried to write.
*/
case SUN50I_IOMMU_ACI_RD:
dir = IOMMU_FAULT_WRITE;
break;
/*
* If we are in the write-only domain, then it means
* we tried to read.
*/
case SUN50I_IOMMU_ACI_WR:
/*
* If we are in the domain without any permission, we
* can't really tell. Let's default to a read
* operation.
*/
case SUN50I_IOMMU_ACI_NONE:
/* WTF? */
case SUN50I_IOMMU_ACI_RD_WR:
default:
dir = IOMMU_FAULT_READ;
break;
}
/*
* If the address is not in the page table, we can't get what
* operation triggered the fault. Assume it's a read
* operation.
*/
sun50i_iommu_report_fault(iommu, master, iova, dir);
return iova;
}
static irqreturn_t sun50i_iommu_irq(int irq, void *dev_id)
{
u32 status, l1_status, l2_status, resets;
struct sun50i_iommu *iommu = dev_id;
spin_lock(&iommu->iommu_lock);
status = iommu_read(iommu, IOMMU_INT_STA_REG);
if (!(status & IOMMU_INT_MASK)) {
spin_unlock(&iommu->iommu_lock);
return IRQ_NONE;
}
l1_status = iommu_read(iommu, IOMMU_L1PG_INT_REG);
l2_status = iommu_read(iommu, IOMMU_L2PG_INT_REG);
if (status & IOMMU_INT_INVALID_L2PG)
sun50i_iommu_handle_pt_irq(iommu,
IOMMU_INT_ERR_ADDR_L2_REG,
IOMMU_L2PG_INT_REG);
else if (status & IOMMU_INT_INVALID_L1PG)
sun50i_iommu_handle_pt_irq(iommu,
IOMMU_INT_ERR_ADDR_L1_REG,
IOMMU_L1PG_INT_REG);
else
sun50i_iommu_handle_perm_irq(iommu);
iommu_write(iommu, IOMMU_INT_CLR_REG, status);
resets = (status | l1_status | l2_status) & IOMMU_INT_MASTER_MASK;
iommu_write(iommu, IOMMU_RESET_REG, ~resets);
iommu_write(iommu, IOMMU_RESET_REG, IOMMU_RESET_RELEASE_ALL);
spin_unlock(&iommu->iommu_lock);
return IRQ_HANDLED;
}
static int sun50i_iommu_probe(struct platform_device *pdev)
{
struct sun50i_iommu *iommu;
int ret, irq;
iommu = devm_kzalloc(&pdev->dev, sizeof(*iommu), GFP_KERNEL);
if (!iommu)
return -ENOMEM;
spin_lock_init(&iommu->iommu_lock);
iommu->domain = &sun50i_iommu_identity_domain;
platform_set_drvdata(pdev, iommu);
iommu->dev = &pdev->dev;
iommu->pt_pool = kmem_cache_create(dev_name(&pdev->dev),
PT_SIZE, PT_SIZE,
SLAB_HWCACHE_ALIGN,
NULL);
if (!iommu->pt_pool)
return -ENOMEM;
iommu->base = devm_platform_ioremap_resource(pdev, 0);
if (IS_ERR(iommu->base)) {
ret = PTR_ERR(iommu->base);
goto err_free_cache;
}
irq = platform_get_irq(pdev, 0);
if (irq < 0) {
ret = irq;
goto err_free_cache;
}
iommu->clk = devm_clk_get(&pdev->dev, NULL);
if (IS_ERR(iommu->clk)) {
dev_err(&pdev->dev, "Couldn't get our clock.\n");
ret = PTR_ERR(iommu->clk);
goto err_free_cache;
}
iommu->reset = devm_reset_control_get(&pdev->dev, NULL);
if (IS_ERR(iommu->reset)) {
dev_err(&pdev->dev, "Couldn't get our reset line.\n");
ret = PTR_ERR(iommu->reset);
goto err_free_cache;
}
ret = iommu_device_sysfs_add(&iommu->iommu, &pdev->dev,
NULL, dev_name(&pdev->dev));
if (ret)
goto err_free_cache;
ret = iommu_device_register(&iommu->iommu, &sun50i_iommu_ops, &pdev->dev);
if (ret)
goto err_remove_sysfs;
ret = devm_request_irq(&pdev->dev, irq, sun50i_iommu_irq, 0,
dev_name(&pdev->dev), iommu);
if (ret < 0)
goto err_unregister;
return 0;
err_unregister:
iommu_device_unregister(&iommu->iommu);
err_remove_sysfs:
iommu_device_sysfs_remove(&iommu->iommu);
err_free_cache:
kmem_cache_destroy(iommu->pt_pool);
return ret;
}
static const struct of_device_id sun50i_iommu_dt[] = {
{ .compatible = "allwinner,sun50i-h6-iommu", },
{ /* sentinel */ },
};
MODULE_DEVICE_TABLE(of, sun50i_iommu_dt);
static struct platform_driver sun50i_iommu_driver = {
.driver = {
.name = "sun50i-iommu",
.of_match_table = sun50i_iommu_dt,
.suppress_bind_attrs = true,
}
};
builtin_platform_driver_probe(sun50i_iommu_driver, sun50i_iommu_probe);
MODULE_DESCRIPTION("Allwinner H6 IOMMU driver");
MODULE_AUTHOR("Maxime Ripard <maxime@cerno.tech>");
MODULE_AUTHOR("zhuxianbin <zhuxianbin@allwinnertech.com>");