linux-sg2042/drivers/iommu/rockchip-iommu.c

1039 lines
27 KiB
C

/*
* 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.
*/
#include <asm/cacheflush.h>
#include <asm/pgtable.h>
#include <linux/compiler.h>
#include <linux/delay.h>
#include <linux/device.h>
#include <linux/errno.h>
#include <linux/interrupt.h>
#include <linux/io.h>
#include <linux/iommu.h>
#include <linux/jiffies.h>
#include <linux/list.h>
#include <linux/mm.h>
#include <linux/module.h>
#include <linux/of.h>
#include <linux/of_platform.h>
#include <linux/platform_device.h>
#include <linux/slab.h>
#include <linux/spinlock.h>
/** MMU register offsets */
#define RK_MMU_DTE_ADDR 0x00 /* Directory table address */
#define RK_MMU_STATUS 0x04
#define RK_MMU_COMMAND 0x08
#define RK_MMU_PAGE_FAULT_ADDR 0x0C /* IOVA of last page fault */
#define RK_MMU_ZAP_ONE_LINE 0x10 /* Shootdown one IOTLB entry */
#define RK_MMU_INT_RAWSTAT 0x14 /* IRQ status ignoring mask */
#define RK_MMU_INT_CLEAR 0x18 /* Acknowledge and re-arm irq */
#define RK_MMU_INT_MASK 0x1C /* IRQ enable */
#define RK_MMU_INT_STATUS 0x20 /* IRQ status after masking */
#define RK_MMU_AUTO_GATING 0x24
#define DTE_ADDR_DUMMY 0xCAFEBABE
#define FORCE_RESET_TIMEOUT 100 /* ms */
/* RK_MMU_STATUS fields */
#define RK_MMU_STATUS_PAGING_ENABLED BIT(0)
#define RK_MMU_STATUS_PAGE_FAULT_ACTIVE BIT(1)
#define RK_MMU_STATUS_STALL_ACTIVE BIT(2)
#define RK_MMU_STATUS_IDLE BIT(3)
#define RK_MMU_STATUS_REPLAY_BUFFER_EMPTY BIT(4)
#define RK_MMU_STATUS_PAGE_FAULT_IS_WRITE BIT(5)
#define RK_MMU_STATUS_STALL_NOT_ACTIVE BIT(31)
/* RK_MMU_COMMAND command values */
#define RK_MMU_CMD_ENABLE_PAGING 0 /* Enable memory translation */
#define RK_MMU_CMD_DISABLE_PAGING 1 /* Disable memory translation */
#define RK_MMU_CMD_ENABLE_STALL 2 /* Stall paging to allow other cmds */
#define RK_MMU_CMD_DISABLE_STALL 3 /* Stop stall re-enables paging */
#define RK_MMU_CMD_ZAP_CACHE 4 /* Shoot down entire IOTLB */
#define RK_MMU_CMD_PAGE_FAULT_DONE 5 /* Clear page fault */
#define RK_MMU_CMD_FORCE_RESET 6 /* Reset all registers */
/* RK_MMU_INT_* register fields */
#define RK_MMU_IRQ_PAGE_FAULT 0x01 /* page fault */
#define RK_MMU_IRQ_BUS_ERROR 0x02 /* bus read error */
#define RK_MMU_IRQ_MASK (RK_MMU_IRQ_PAGE_FAULT | RK_MMU_IRQ_BUS_ERROR)
#define NUM_DT_ENTRIES 1024
#define NUM_PT_ENTRIES 1024
#define SPAGE_ORDER 12
#define SPAGE_SIZE (1 << SPAGE_ORDER)
/*
* Support mapping any size that fits in one page table:
* 4 KiB to 4 MiB
*/
#define RK_IOMMU_PGSIZE_BITMAP 0x007ff000
#define IOMMU_REG_POLL_COUNT_FAST 1000
struct rk_iommu_domain {
struct list_head iommus;
u32 *dt; /* page directory table */
spinlock_t iommus_lock; /* lock for iommus list */
spinlock_t dt_lock; /* lock for modifying page directory table */
};
struct rk_iommu {
struct device *dev;
void __iomem *base;
int irq;
struct list_head node; /* entry in rk_iommu_domain.iommus */
struct iommu_domain *domain; /* domain to which iommu is attached */
};
static inline void rk_table_flush(u32 *va, unsigned int count)
{
phys_addr_t pa_start = virt_to_phys(va);
phys_addr_t pa_end = virt_to_phys(va + count);
size_t size = pa_end - pa_start;
__cpuc_flush_dcache_area(va, size);
outer_flush_range(pa_start, pa_end);
}
/**
* Inspired by _wait_for in intel_drv.h
* This is NOT safe for use in interrupt context.
*
* Note that it's important that we check the condition again after having
* timed out, since the timeout could be due to preemption or similar and
* we've never had a chance to check the condition before the timeout.
*/
#define rk_wait_for(COND, MS) ({ \
unsigned long timeout__ = jiffies + msecs_to_jiffies(MS) + 1; \
int ret__ = 0; \
while (!(COND)) { \
if (time_after(jiffies, timeout__)) { \
ret__ = (COND) ? 0 : -ETIMEDOUT; \
break; \
} \
usleep_range(50, 100); \
} \
ret__; \
})
/*
* The Rockchip rk3288 iommu uses a 2-level page table.
* The first level is the "Directory Table" (DT).
* The DT consists of 1024 4-byte Directory Table Entries (DTEs), each pointing
* to a "Page Table".
* The second level is the 1024 Page Tables (PT).
* Each PT consists of 1024 4-byte Page Table Entries (PTEs), each pointing to
* a 4 KB page of physical memory.
*
* The DT and each PT fits in a single 4 KB page (4-bytes * 1024 entries).
* Each iommu device has a MMU_DTE_ADDR register that contains the physical
* address of the start of the DT page.
*
* The structure of the page table is as follows:
*
* DT
* MMU_DTE_ADDR -> +-----+
* | |
* +-----+ PT
* | DTE | -> +-----+
* +-----+ | | Memory
* | | +-----+ Page
* | | | PTE | -> +-----+
* +-----+ +-----+ | |
* | | | |
* | | | |
* +-----+ | |
* | |
* | |
* +-----+
*/
/*
* Each DTE has a PT address and a valid bit:
* +---------------------+-----------+-+
* | PT address | Reserved |V|
* +---------------------+-----------+-+
* 31:12 - PT address (PTs always starts on a 4 KB boundary)
* 11: 1 - Reserved
* 0 - 1 if PT @ PT address is valid
*/
#define RK_DTE_PT_ADDRESS_MASK 0xfffff000
#define RK_DTE_PT_VALID BIT(0)
static inline phys_addr_t rk_dte_pt_address(u32 dte)
{
return (phys_addr_t)dte & RK_DTE_PT_ADDRESS_MASK;
}
static inline bool rk_dte_is_pt_valid(u32 dte)
{
return dte & RK_DTE_PT_VALID;
}
static u32 rk_mk_dte(u32 *pt)
{
phys_addr_t pt_phys = virt_to_phys(pt);
return (pt_phys & RK_DTE_PT_ADDRESS_MASK) | RK_DTE_PT_VALID;
}
/*
* Each PTE has a Page address, some flags and a valid bit:
* +---------------------+---+-------+-+
* | Page address |Rsv| Flags |V|
* +---------------------+---+-------+-+
* 31:12 - Page address (Pages always start on a 4 KB boundary)
* 11: 9 - Reserved
* 8: 1 - Flags
* 8 - Read allocate - allocate cache space on read misses
* 7 - Read cache - enable cache & prefetch of data
* 6 - Write buffer - enable delaying writes on their way to memory
* 5 - Write allocate - allocate cache space on write misses
* 4 - Write cache - different writes can be merged together
* 3 - Override cache attributes
* if 1, bits 4-8 control cache attributes
* if 0, the system bus defaults are used
* 2 - Writable
* 1 - Readable
* 0 - 1 if Page @ Page address is valid
*/
#define RK_PTE_PAGE_ADDRESS_MASK 0xfffff000
#define RK_PTE_PAGE_FLAGS_MASK 0x000001fe
#define RK_PTE_PAGE_WRITABLE BIT(2)
#define RK_PTE_PAGE_READABLE BIT(1)
#define RK_PTE_PAGE_VALID BIT(0)
static inline phys_addr_t rk_pte_page_address(u32 pte)
{
return (phys_addr_t)pte & RK_PTE_PAGE_ADDRESS_MASK;
}
static inline bool rk_pte_is_page_valid(u32 pte)
{
return pte & RK_PTE_PAGE_VALID;
}
/* TODO: set cache flags per prot IOMMU_CACHE */
static u32 rk_mk_pte(phys_addr_t page, int prot)
{
u32 flags = 0;
flags |= (prot & IOMMU_READ) ? RK_PTE_PAGE_READABLE : 0;
flags |= (prot & IOMMU_WRITE) ? RK_PTE_PAGE_WRITABLE : 0;
page &= RK_PTE_PAGE_ADDRESS_MASK;
return page | flags | RK_PTE_PAGE_VALID;
}
static u32 rk_mk_pte_invalid(u32 pte)
{
return pte & ~RK_PTE_PAGE_VALID;
}
/*
* rk3288 iova (IOMMU Virtual Address) format
* 31 22.21 12.11 0
* +-----------+-----------+-------------+
* | DTE index | PTE index | Page offset |
* +-----------+-----------+-------------+
* 31:22 - DTE index - index of DTE in DT
* 21:12 - PTE index - index of PTE in PT @ DTE.pt_address
* 11: 0 - Page offset - offset into page @ PTE.page_address
*/
#define RK_IOVA_DTE_MASK 0xffc00000
#define RK_IOVA_DTE_SHIFT 22
#define RK_IOVA_PTE_MASK 0x003ff000
#define RK_IOVA_PTE_SHIFT 12
#define RK_IOVA_PAGE_MASK 0x00000fff
#define RK_IOVA_PAGE_SHIFT 0
static u32 rk_iova_dte_index(dma_addr_t iova)
{
return (u32)(iova & RK_IOVA_DTE_MASK) >> RK_IOVA_DTE_SHIFT;
}
static u32 rk_iova_pte_index(dma_addr_t iova)
{
return (u32)(iova & RK_IOVA_PTE_MASK) >> RK_IOVA_PTE_SHIFT;
}
static u32 rk_iova_page_offset(dma_addr_t iova)
{
return (u32)(iova & RK_IOVA_PAGE_MASK) >> RK_IOVA_PAGE_SHIFT;
}
static u32 rk_iommu_read(struct rk_iommu *iommu, u32 offset)
{
return readl(iommu->base + offset);
}
static void rk_iommu_write(struct rk_iommu *iommu, u32 offset, u32 value)
{
writel(value, iommu->base + offset);
}
static void rk_iommu_command(struct rk_iommu *iommu, u32 command)
{
writel(command, iommu->base + RK_MMU_COMMAND);
}
static void rk_iommu_zap_lines(struct rk_iommu *iommu, dma_addr_t iova,
size_t size)
{
dma_addr_t iova_end = iova + size;
/*
* TODO(djkurtz): Figure out when it is more efficient to shootdown the
* entire iotlb rather than iterate over individual iovas.
*/
for (; iova < iova_end; iova += SPAGE_SIZE)
rk_iommu_write(iommu, RK_MMU_ZAP_ONE_LINE, iova);
}
static bool rk_iommu_is_stall_active(struct rk_iommu *iommu)
{
return rk_iommu_read(iommu, RK_MMU_STATUS) & RK_MMU_STATUS_STALL_ACTIVE;
}
static bool rk_iommu_is_paging_enabled(struct rk_iommu *iommu)
{
return rk_iommu_read(iommu, RK_MMU_STATUS) &
RK_MMU_STATUS_PAGING_ENABLED;
}
static int rk_iommu_enable_stall(struct rk_iommu *iommu)
{
int ret;
if (rk_iommu_is_stall_active(iommu))
return 0;
/* Stall can only be enabled if paging is enabled */
if (!rk_iommu_is_paging_enabled(iommu))
return 0;
rk_iommu_command(iommu, RK_MMU_CMD_ENABLE_STALL);
ret = rk_wait_for(rk_iommu_is_stall_active(iommu), 1);
if (ret)
dev_err(iommu->dev, "Enable stall request timed out, status: %#08x\n",
rk_iommu_read(iommu, RK_MMU_STATUS));
return ret;
}
static int rk_iommu_disable_stall(struct rk_iommu *iommu)
{
int ret;
if (!rk_iommu_is_stall_active(iommu))
return 0;
rk_iommu_command(iommu, RK_MMU_CMD_DISABLE_STALL);
ret = rk_wait_for(!rk_iommu_is_stall_active(iommu), 1);
if (ret)
dev_err(iommu->dev, "Disable stall request timed out, status: %#08x\n",
rk_iommu_read(iommu, RK_MMU_STATUS));
return ret;
}
static int rk_iommu_enable_paging(struct rk_iommu *iommu)
{
int ret;
if (rk_iommu_is_paging_enabled(iommu))
return 0;
rk_iommu_command(iommu, RK_MMU_CMD_ENABLE_PAGING);
ret = rk_wait_for(rk_iommu_is_paging_enabled(iommu), 1);
if (ret)
dev_err(iommu->dev, "Enable paging request timed out, status: %#08x\n",
rk_iommu_read(iommu, RK_MMU_STATUS));
return ret;
}
static int rk_iommu_disable_paging(struct rk_iommu *iommu)
{
int ret;
if (!rk_iommu_is_paging_enabled(iommu))
return 0;
rk_iommu_command(iommu, RK_MMU_CMD_DISABLE_PAGING);
ret = rk_wait_for(!rk_iommu_is_paging_enabled(iommu), 1);
if (ret)
dev_err(iommu->dev, "Disable paging request timed out, status: %#08x\n",
rk_iommu_read(iommu, RK_MMU_STATUS));
return ret;
}
static int rk_iommu_force_reset(struct rk_iommu *iommu)
{
int ret;
u32 dte_addr;
/*
* Check if register DTE_ADDR is working by writing DTE_ADDR_DUMMY
* and verifying that upper 5 nybbles are read back.
*/
rk_iommu_write(iommu, RK_MMU_DTE_ADDR, DTE_ADDR_DUMMY);
dte_addr = rk_iommu_read(iommu, RK_MMU_DTE_ADDR);
if (dte_addr != (DTE_ADDR_DUMMY & RK_DTE_PT_ADDRESS_MASK)) {
dev_err(iommu->dev, "Error during raw reset. MMU_DTE_ADDR is not functioning\n");
return -EFAULT;
}
rk_iommu_command(iommu, RK_MMU_CMD_FORCE_RESET);
ret = rk_wait_for(rk_iommu_read(iommu, RK_MMU_DTE_ADDR) == 0x00000000,
FORCE_RESET_TIMEOUT);
if (ret)
dev_err(iommu->dev, "FORCE_RESET command timed out\n");
return ret;
}
static void log_iova(struct rk_iommu *iommu, dma_addr_t iova)
{
u32 dte_index, pte_index, page_offset;
u32 mmu_dte_addr;
phys_addr_t mmu_dte_addr_phys, dte_addr_phys;
u32 *dte_addr;
u32 dte;
phys_addr_t pte_addr_phys = 0;
u32 *pte_addr = NULL;
u32 pte = 0;
phys_addr_t page_addr_phys = 0;
u32 page_flags = 0;
dte_index = rk_iova_dte_index(iova);
pte_index = rk_iova_pte_index(iova);
page_offset = rk_iova_page_offset(iova);
mmu_dte_addr = rk_iommu_read(iommu, RK_MMU_DTE_ADDR);
mmu_dte_addr_phys = (phys_addr_t)mmu_dte_addr;
dte_addr_phys = mmu_dte_addr_phys + (4 * dte_index);
dte_addr = phys_to_virt(dte_addr_phys);
dte = *dte_addr;
if (!rk_dte_is_pt_valid(dte))
goto print_it;
pte_addr_phys = rk_dte_pt_address(dte) + (pte_index * 4);
pte_addr = phys_to_virt(pte_addr_phys);
pte = *pte_addr;
if (!rk_pte_is_page_valid(pte))
goto print_it;
page_addr_phys = rk_pte_page_address(pte) + page_offset;
page_flags = pte & RK_PTE_PAGE_FLAGS_MASK;
print_it:
dev_err(iommu->dev, "iova = %pad: dte_index: %#03x pte_index: %#03x page_offset: %#03x\n",
&iova, dte_index, pte_index, page_offset);
dev_err(iommu->dev, "mmu_dte_addr: %pa dte@%pa: %#08x valid: %u pte@%pa: %#08x valid: %u page@%pa flags: %#03x\n",
&mmu_dte_addr_phys, &dte_addr_phys, dte,
rk_dte_is_pt_valid(dte), &pte_addr_phys, pte,
rk_pte_is_page_valid(pte), &page_addr_phys, page_flags);
}
static irqreturn_t rk_iommu_irq(int irq, void *dev_id)
{
struct rk_iommu *iommu = dev_id;
u32 status;
u32 int_status;
dma_addr_t iova;
int_status = rk_iommu_read(iommu, RK_MMU_INT_STATUS);
if (int_status == 0)
return IRQ_NONE;
iova = rk_iommu_read(iommu, RK_MMU_PAGE_FAULT_ADDR);
if (int_status & RK_MMU_IRQ_PAGE_FAULT) {
int flags;
status = rk_iommu_read(iommu, RK_MMU_STATUS);
flags = (status & RK_MMU_STATUS_PAGE_FAULT_IS_WRITE) ?
IOMMU_FAULT_WRITE : IOMMU_FAULT_READ;
dev_err(iommu->dev, "Page fault at %pad of type %s\n",
&iova,
(flags == IOMMU_FAULT_WRITE) ? "write" : "read");
log_iova(iommu, iova);
/*
* Report page fault to any installed handlers.
* Ignore the return code, though, since we always zap cache
* and clear the page fault anyway.
*/
if (iommu->domain)
report_iommu_fault(iommu->domain, iommu->dev, iova,
flags);
else
dev_err(iommu->dev, "Page fault while iommu not attached to domain?\n");
rk_iommu_command(iommu, RK_MMU_CMD_ZAP_CACHE);
rk_iommu_command(iommu, RK_MMU_CMD_PAGE_FAULT_DONE);
}
if (int_status & RK_MMU_IRQ_BUS_ERROR)
dev_err(iommu->dev, "BUS_ERROR occurred at %pad\n", &iova);
if (int_status & ~RK_MMU_IRQ_MASK)
dev_err(iommu->dev, "unexpected int_status: %#08x\n",
int_status);
rk_iommu_write(iommu, RK_MMU_INT_CLEAR, int_status);
return IRQ_HANDLED;
}
static phys_addr_t rk_iommu_iova_to_phys(struct iommu_domain *domain,
dma_addr_t iova)
{
struct rk_iommu_domain *rk_domain = domain->priv;
unsigned long flags;
phys_addr_t pt_phys, phys = 0;
u32 dte, pte;
u32 *page_table;
spin_lock_irqsave(&rk_domain->dt_lock, flags);
dte = rk_domain->dt[rk_iova_dte_index(iova)];
if (!rk_dte_is_pt_valid(dte))
goto out;
pt_phys = rk_dte_pt_address(dte);
page_table = (u32 *)phys_to_virt(pt_phys);
pte = page_table[rk_iova_pte_index(iova)];
if (!rk_pte_is_page_valid(pte))
goto out;
phys = rk_pte_page_address(pte) + rk_iova_page_offset(iova);
out:
spin_unlock_irqrestore(&rk_domain->dt_lock, flags);
return phys;
}
static void rk_iommu_zap_iova(struct rk_iommu_domain *rk_domain,
dma_addr_t iova, size_t size)
{
struct list_head *pos;
unsigned long flags;
/* shootdown these iova from all iommus using this domain */
spin_lock_irqsave(&rk_domain->iommus_lock, flags);
list_for_each(pos, &rk_domain->iommus) {
struct rk_iommu *iommu;
iommu = list_entry(pos, struct rk_iommu, node);
rk_iommu_zap_lines(iommu, iova, size);
}
spin_unlock_irqrestore(&rk_domain->iommus_lock, flags);
}
static u32 *rk_dte_get_page_table(struct rk_iommu_domain *rk_domain,
dma_addr_t iova)
{
u32 *page_table, *dte_addr;
u32 dte;
phys_addr_t pt_phys;
assert_spin_locked(&rk_domain->dt_lock);
dte_addr = &rk_domain->dt[rk_iova_dte_index(iova)];
dte = *dte_addr;
if (rk_dte_is_pt_valid(dte))
goto done;
page_table = (u32 *)get_zeroed_page(GFP_ATOMIC | GFP_DMA32);
if (!page_table)
return ERR_PTR(-ENOMEM);
dte = rk_mk_dte(page_table);
*dte_addr = dte;
rk_table_flush(page_table, NUM_PT_ENTRIES);
rk_table_flush(dte_addr, 1);
/*
* Zap the first iova of newly allocated page table so iommu evicts
* old cached value of new dte from the iotlb.
*/
rk_iommu_zap_iova(rk_domain, iova, SPAGE_SIZE);
done:
pt_phys = rk_dte_pt_address(dte);
return (u32 *)phys_to_virt(pt_phys);
}
static size_t rk_iommu_unmap_iova(struct rk_iommu_domain *rk_domain,
u32 *pte_addr, dma_addr_t iova, size_t size)
{
unsigned int pte_count;
unsigned int pte_total = size / SPAGE_SIZE;
assert_spin_locked(&rk_domain->dt_lock);
for (pte_count = 0; pte_count < pte_total; pte_count++) {
u32 pte = pte_addr[pte_count];
if (!rk_pte_is_page_valid(pte))
break;
pte_addr[pte_count] = rk_mk_pte_invalid(pte);
}
rk_table_flush(pte_addr, pte_count);
return pte_count * SPAGE_SIZE;
}
static int rk_iommu_map_iova(struct rk_iommu_domain *rk_domain, u32 *pte_addr,
dma_addr_t iova, phys_addr_t paddr, size_t size,
int prot)
{
unsigned int pte_count;
unsigned int pte_total = size / SPAGE_SIZE;
phys_addr_t page_phys;
assert_spin_locked(&rk_domain->dt_lock);
for (pte_count = 0; pte_count < pte_total; pte_count++) {
u32 pte = pte_addr[pte_count];
if (rk_pte_is_page_valid(pte))
goto unwind;
pte_addr[pte_count] = rk_mk_pte(paddr, prot);
paddr += SPAGE_SIZE;
}
rk_table_flush(pte_addr, pte_count);
return 0;
unwind:
/* Unmap the range of iovas that we just mapped */
rk_iommu_unmap_iova(rk_domain, pte_addr, iova, pte_count * SPAGE_SIZE);
iova += pte_count * SPAGE_SIZE;
page_phys = rk_pte_page_address(pte_addr[pte_count]);
pr_err("iova: %pad already mapped to %pa cannot remap to phys: %pa prot: %#x\n",
&iova, &page_phys, &paddr, prot);
return -EADDRINUSE;
}
static int rk_iommu_map(struct iommu_domain *domain, unsigned long _iova,
phys_addr_t paddr, size_t size, int prot)
{
struct rk_iommu_domain *rk_domain = domain->priv;
unsigned long flags;
dma_addr_t iova = (dma_addr_t)_iova;
u32 *page_table, *pte_addr;
int ret;
spin_lock_irqsave(&rk_domain->dt_lock, flags);
/*
* pgsize_bitmap specifies iova sizes that fit in one page table
* (1024 4-KiB pages = 4 MiB).
* So, size will always be 4096 <= size <= 4194304.
* Since iommu_map() guarantees that both iova and size will be
* aligned, we will always only be mapping from a single dte here.
*/
page_table = rk_dte_get_page_table(rk_domain, iova);
if (IS_ERR(page_table)) {
spin_unlock_irqrestore(&rk_domain->dt_lock, flags);
return PTR_ERR(page_table);
}
pte_addr = &page_table[rk_iova_pte_index(iova)];
ret = rk_iommu_map_iova(rk_domain, pte_addr, iova, paddr, size, prot);
spin_unlock_irqrestore(&rk_domain->dt_lock, flags);
return ret;
}
static size_t rk_iommu_unmap(struct iommu_domain *domain, unsigned long _iova,
size_t size)
{
struct rk_iommu_domain *rk_domain = domain->priv;
unsigned long flags;
dma_addr_t iova = (dma_addr_t)_iova;
phys_addr_t pt_phys;
u32 dte;
u32 *pte_addr;
size_t unmap_size;
spin_lock_irqsave(&rk_domain->dt_lock, flags);
/*
* pgsize_bitmap specifies iova sizes that fit in one page table
* (1024 4-KiB pages = 4 MiB).
* So, size will always be 4096 <= size <= 4194304.
* Since iommu_unmap() guarantees that both iova and size will be
* aligned, we will always only be unmapping from a single dte here.
*/
dte = rk_domain->dt[rk_iova_dte_index(iova)];
/* Just return 0 if iova is unmapped */
if (!rk_dte_is_pt_valid(dte)) {
spin_unlock_irqrestore(&rk_domain->dt_lock, flags);
return 0;
}
pt_phys = rk_dte_pt_address(dte);
pte_addr = (u32 *)phys_to_virt(pt_phys) + rk_iova_pte_index(iova);
unmap_size = rk_iommu_unmap_iova(rk_domain, pte_addr, iova, size);
spin_unlock_irqrestore(&rk_domain->dt_lock, flags);
/* Shootdown iotlb entries for iova range that was just unmapped */
rk_iommu_zap_iova(rk_domain, iova, unmap_size);
return unmap_size;
}
static struct rk_iommu *rk_iommu_from_dev(struct device *dev)
{
struct iommu_group *group;
struct device *iommu_dev;
struct rk_iommu *rk_iommu;
group = iommu_group_get(dev);
if (!group)
return NULL;
iommu_dev = iommu_group_get_iommudata(group);
rk_iommu = dev_get_drvdata(iommu_dev);
iommu_group_put(group);
return rk_iommu;
}
static int rk_iommu_attach_device(struct iommu_domain *domain,
struct device *dev)
{
struct rk_iommu *iommu;
struct rk_iommu_domain *rk_domain = domain->priv;
unsigned long flags;
int ret;
phys_addr_t dte_addr;
/*
* Allow 'virtual devices' (e.g., drm) to attach to domain.
* Such a device does not belong to an iommu group.
*/
iommu = rk_iommu_from_dev(dev);
if (!iommu)
return 0;
ret = rk_iommu_enable_stall(iommu);
if (ret)
return ret;
ret = rk_iommu_force_reset(iommu);
if (ret)
return ret;
iommu->domain = domain;
ret = devm_request_irq(dev, iommu->irq, rk_iommu_irq,
IRQF_SHARED, dev_name(dev), iommu);
if (ret)
return ret;
dte_addr = virt_to_phys(rk_domain->dt);
rk_iommu_write(iommu, RK_MMU_DTE_ADDR, dte_addr);
rk_iommu_command(iommu, RK_MMU_CMD_ZAP_CACHE);
rk_iommu_write(iommu, RK_MMU_INT_MASK, RK_MMU_IRQ_MASK);
ret = rk_iommu_enable_paging(iommu);
if (ret)
return ret;
spin_lock_irqsave(&rk_domain->iommus_lock, flags);
list_add_tail(&iommu->node, &rk_domain->iommus);
spin_unlock_irqrestore(&rk_domain->iommus_lock, flags);
dev_info(dev, "Attached to iommu domain\n");
rk_iommu_disable_stall(iommu);
return 0;
}
static void rk_iommu_detach_device(struct iommu_domain *domain,
struct device *dev)
{
struct rk_iommu *iommu;
struct rk_iommu_domain *rk_domain = domain->priv;
unsigned long flags;
/* Allow 'virtual devices' (eg drm) to detach from domain */
iommu = rk_iommu_from_dev(dev);
if (!iommu)
return;
spin_lock_irqsave(&rk_domain->iommus_lock, flags);
list_del_init(&iommu->node);
spin_unlock_irqrestore(&rk_domain->iommus_lock, flags);
/* Ignore error while disabling, just keep going */
rk_iommu_enable_stall(iommu);
rk_iommu_disable_paging(iommu);
rk_iommu_write(iommu, RK_MMU_INT_MASK, 0);
rk_iommu_write(iommu, RK_MMU_DTE_ADDR, 0);
rk_iommu_disable_stall(iommu);
devm_free_irq(dev, iommu->irq, iommu);
iommu->domain = NULL;
dev_info(dev, "Detached from iommu domain\n");
}
static int rk_iommu_domain_init(struct iommu_domain *domain)
{
struct rk_iommu_domain *rk_domain;
rk_domain = kzalloc(sizeof(*rk_domain), GFP_KERNEL);
if (!rk_domain)
return -ENOMEM;
/*
* rk32xx iommus use a 2 level pagetable.
* Each level1 (dt) and level2 (pt) table has 1024 4-byte entries.
* Allocate one 4 KiB page for each table.
*/
rk_domain->dt = (u32 *)get_zeroed_page(GFP_KERNEL | GFP_DMA32);
if (!rk_domain->dt)
goto err_dt;
rk_table_flush(rk_domain->dt, NUM_DT_ENTRIES);
spin_lock_init(&rk_domain->iommus_lock);
spin_lock_init(&rk_domain->dt_lock);
INIT_LIST_HEAD(&rk_domain->iommus);
domain->priv = rk_domain;
return 0;
err_dt:
kfree(rk_domain);
return -ENOMEM;
}
static void rk_iommu_domain_destroy(struct iommu_domain *domain)
{
struct rk_iommu_domain *rk_domain = domain->priv;
int i;
WARN_ON(!list_empty(&rk_domain->iommus));
for (i = 0; i < NUM_DT_ENTRIES; i++) {
u32 dte = rk_domain->dt[i];
if (rk_dte_is_pt_valid(dte)) {
phys_addr_t pt_phys = rk_dte_pt_address(dte);
u32 *page_table = phys_to_virt(pt_phys);
free_page((unsigned long)page_table);
}
}
free_page((unsigned long)rk_domain->dt);
kfree(domain->priv);
domain->priv = NULL;
}
static bool rk_iommu_is_dev_iommu_master(struct device *dev)
{
struct device_node *np = dev->of_node;
int ret;
/*
* An iommu master has an iommus property containing a list of phandles
* to iommu nodes, each with an #iommu-cells property with value 0.
*/
ret = of_count_phandle_with_args(np, "iommus", "#iommu-cells");
return (ret > 0);
}
static int rk_iommu_group_set_iommudata(struct iommu_group *group,
struct device *dev)
{
struct device_node *np = dev->of_node;
struct platform_device *pd;
int ret;
struct of_phandle_args args;
/*
* An iommu master has an iommus property containing a list of phandles
* to iommu nodes, each with an #iommu-cells property with value 0.
*/
ret = of_parse_phandle_with_args(np, "iommus", "#iommu-cells", 0,
&args);
if (ret) {
dev_err(dev, "of_parse_phandle_with_args(%s) => %d\n",
np->full_name, ret);
return ret;
}
if (args.args_count != 0) {
dev_err(dev, "incorrect number of iommu params found for %s (found %d, expected 0)\n",
args.np->full_name, args.args_count);
return -EINVAL;
}
pd = of_find_device_by_node(args.np);
of_node_put(args.np);
if (!pd) {
dev_err(dev, "iommu %s not found\n", args.np->full_name);
return -EPROBE_DEFER;
}
/* TODO(djkurtz): handle multiple slave iommus for a single master */
iommu_group_set_iommudata(group, &pd->dev, NULL);
return 0;
}
static int rk_iommu_add_device(struct device *dev)
{
struct iommu_group *group;
int ret;
if (!rk_iommu_is_dev_iommu_master(dev))
return -ENODEV;
group = iommu_group_get(dev);
if (!group) {
group = iommu_group_alloc();
if (IS_ERR(group)) {
dev_err(dev, "Failed to allocate IOMMU group\n");
return PTR_ERR(group);
}
}
ret = iommu_group_add_device(group, dev);
if (ret)
goto err_put_group;
ret = rk_iommu_group_set_iommudata(group, dev);
if (ret)
goto err_remove_device;
iommu_group_put(group);
return 0;
err_remove_device:
iommu_group_remove_device(dev);
err_put_group:
iommu_group_put(group);
return ret;
}
static void rk_iommu_remove_device(struct device *dev)
{
if (!rk_iommu_is_dev_iommu_master(dev))
return;
iommu_group_remove_device(dev);
}
static const struct iommu_ops rk_iommu_ops = {
.domain_init = rk_iommu_domain_init,
.domain_destroy = rk_iommu_domain_destroy,
.attach_dev = rk_iommu_attach_device,
.detach_dev = rk_iommu_detach_device,
.map = rk_iommu_map,
.unmap = rk_iommu_unmap,
.add_device = rk_iommu_add_device,
.remove_device = rk_iommu_remove_device,
.iova_to_phys = rk_iommu_iova_to_phys,
.pgsize_bitmap = RK_IOMMU_PGSIZE_BITMAP,
};
static int rk_iommu_probe(struct platform_device *pdev)
{
struct device *dev = &pdev->dev;
struct rk_iommu *iommu;
struct resource *res;
iommu = devm_kzalloc(dev, sizeof(*iommu), GFP_KERNEL);
if (!iommu)
return -ENOMEM;
platform_set_drvdata(pdev, iommu);
iommu->dev = dev;
res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
iommu->base = devm_ioremap_resource(&pdev->dev, res);
if (IS_ERR(iommu->base))
return PTR_ERR(iommu->base);
iommu->irq = platform_get_irq(pdev, 0);
if (iommu->irq < 0) {
dev_err(dev, "Failed to get IRQ, %d\n", iommu->irq);
return -ENXIO;
}
return 0;
}
static int rk_iommu_remove(struct platform_device *pdev)
{
return 0;
}
#ifdef CONFIG_OF
static const struct of_device_id rk_iommu_dt_ids[] = {
{ .compatible = "rockchip,iommu" },
{ /* sentinel */ }
};
MODULE_DEVICE_TABLE(of, rk_iommu_dt_ids);
#endif
static struct platform_driver rk_iommu_driver = {
.probe = rk_iommu_probe,
.remove = rk_iommu_remove,
.driver = {
.name = "rk_iommu",
.owner = THIS_MODULE,
.of_match_table = of_match_ptr(rk_iommu_dt_ids),
},
};
static int __init rk_iommu_init(void)
{
int ret;
ret = bus_set_iommu(&platform_bus_type, &rk_iommu_ops);
if (ret)
return ret;
return platform_driver_register(&rk_iommu_driver);
}
static void __exit rk_iommu_exit(void)
{
platform_driver_unregister(&rk_iommu_driver);
}
subsys_initcall(rk_iommu_init);
module_exit(rk_iommu_exit);
MODULE_DESCRIPTION("IOMMU API for Rockchip");
MODULE_AUTHOR("Simon Xue <xxm@rock-chips.com> and Daniel Kurtz <djkurtz@chromium.org>");
MODULE_ALIAS("platform:rockchip-iommu");
MODULE_LICENSE("GPL v2");