linux/arch/sparc/mm/io-unit.c

264 lines
6.9 KiB
C

// SPDX-License-Identifier: GPL-2.0
/*
* io-unit.c: IO-UNIT specific routines for memory management.
*
* Copyright (C) 1997,1998 Jakub Jelinek (jj@sunsite.mff.cuni.cz)
*/
#include <linux/kernel.h>
#include <linux/init.h>
#include <linux/slab.h>
#include <linux/spinlock.h>
#include <linux/mm.h>
#include <linux/highmem.h> /* pte_offset_map => kmap_atomic */
#include <linux/bitops.h>
#include <linux/scatterlist.h>
#include <linux/of.h>
#include <linux/of_device.h>
#include <asm/pgalloc.h>
#include <asm/pgtable.h>
#include <asm/io.h>
#include <asm/io-unit.h>
#include <asm/mxcc.h>
#include <asm/cacheflush.h>
#include <asm/tlbflush.h>
#include <asm/dma.h>
#include <asm/oplib.h>
#include "mm_32.h"
/* #define IOUNIT_DEBUG */
#ifdef IOUNIT_DEBUG
#define IOD(x) printk(x)
#else
#define IOD(x) do { } while (0)
#endif
#define IOPERM (IOUPTE_CACHE | IOUPTE_WRITE | IOUPTE_VALID)
#define MKIOPTE(phys) __iopte((((phys)>>4) & IOUPTE_PAGE) | IOPERM)
static void __init iounit_iommu_init(struct platform_device *op)
{
struct iounit_struct *iounit;
iopte_t __iomem *xpt;
iopte_t __iomem *xptend;
iounit = kzalloc(sizeof(struct iounit_struct), GFP_ATOMIC);
if (!iounit) {
prom_printf("SUN4D: Cannot alloc iounit, halting.\n");
prom_halt();
}
iounit->limit[0] = IOUNIT_BMAP1_START;
iounit->limit[1] = IOUNIT_BMAP2_START;
iounit->limit[2] = IOUNIT_BMAPM_START;
iounit->limit[3] = IOUNIT_BMAPM_END;
iounit->rotor[1] = IOUNIT_BMAP2_START;
iounit->rotor[2] = IOUNIT_BMAPM_START;
xpt = of_ioremap(&op->resource[2], 0, PAGE_SIZE * 16, "XPT");
if (!xpt) {
prom_printf("SUN4D: Cannot map External Page Table.");
prom_halt();
}
op->dev.archdata.iommu = iounit;
iounit->page_table = xpt;
spin_lock_init(&iounit->lock);
xptend = iounit->page_table + (16 * PAGE_SIZE) / sizeof(iopte_t);
for (; xpt < xptend; xpt++)
sbus_writel(0, xpt);
}
static int __init iounit_init(void)
{
extern void sun4d_init_sbi_irq(void);
struct device_node *dp;
for_each_node_by_name(dp, "sbi") {
struct platform_device *op = of_find_device_by_node(dp);
iounit_iommu_init(op);
of_propagate_archdata(op);
}
sun4d_init_sbi_irq();
return 0;
}
subsys_initcall(iounit_init);
/* One has to hold iounit->lock to call this */
static unsigned long iounit_get_area(struct iounit_struct *iounit, unsigned long vaddr, int size)
{
int i, j, k, npages;
unsigned long rotor, scan, limit;
iopte_t iopte;
npages = ((vaddr & ~PAGE_MASK) + size + (PAGE_SIZE-1)) >> PAGE_SHIFT;
/* A tiny bit of magic ingredience :) */
switch (npages) {
case 1: i = 0x0231; break;
case 2: i = 0x0132; break;
default: i = 0x0213; break;
}
IOD(("iounit_get_area(%08lx,%d[%d])=", vaddr, size, npages));
next: j = (i & 15);
rotor = iounit->rotor[j - 1];
limit = iounit->limit[j];
scan = rotor;
nexti: scan = find_next_zero_bit(iounit->bmap, limit, scan);
if (scan + npages > limit) {
if (limit != rotor) {
limit = rotor;
scan = iounit->limit[j - 1];
goto nexti;
}
i >>= 4;
if (!(i & 15))
panic("iounit_get_area: Couldn't find free iopte slots for (%08lx,%d)\n", vaddr, size);
goto next;
}
for (k = 1, scan++; k < npages; k++)
if (test_bit(scan++, iounit->bmap))
goto nexti;
iounit->rotor[j - 1] = (scan < limit) ? scan : iounit->limit[j - 1];
scan -= npages;
iopte = MKIOPTE(__pa(vaddr & PAGE_MASK));
vaddr = IOUNIT_DMA_BASE + (scan << PAGE_SHIFT) + (vaddr & ~PAGE_MASK);
for (k = 0; k < npages; k++, iopte = __iopte(iopte_val(iopte) + 0x100), scan++) {
set_bit(scan, iounit->bmap);
sbus_writel(iopte_val(iopte), &iounit->page_table[scan]);
}
IOD(("%08lx\n", vaddr));
return vaddr;
}
static __u32 iounit_get_scsi_one(struct device *dev, char *vaddr, unsigned long len)
{
struct iounit_struct *iounit = dev->archdata.iommu;
unsigned long ret, flags;
spin_lock_irqsave(&iounit->lock, flags);
ret = iounit_get_area(iounit, (unsigned long)vaddr, len);
spin_unlock_irqrestore(&iounit->lock, flags);
return ret;
}
static void iounit_get_scsi_sgl(struct device *dev, struct scatterlist *sg, int sz)
{
struct iounit_struct *iounit = dev->archdata.iommu;
unsigned long flags;
/* FIXME: Cache some resolved pages - often several sg entries are to the same page */
spin_lock_irqsave(&iounit->lock, flags);
while (sz != 0) {
--sz;
sg->dma_address = iounit_get_area(iounit, (unsigned long) sg_virt(sg), sg->length);
sg->dma_length = sg->length;
sg = sg_next(sg);
}
spin_unlock_irqrestore(&iounit->lock, flags);
}
static void iounit_release_scsi_one(struct device *dev, __u32 vaddr, unsigned long len)
{
struct iounit_struct *iounit = dev->archdata.iommu;
unsigned long flags;
spin_lock_irqsave(&iounit->lock, flags);
len = ((vaddr & ~PAGE_MASK) + len + (PAGE_SIZE-1)) >> PAGE_SHIFT;
vaddr = (vaddr - IOUNIT_DMA_BASE) >> PAGE_SHIFT;
IOD(("iounit_release %08lx-%08lx\n", (long)vaddr, (long)len+vaddr));
for (len += vaddr; vaddr < len; vaddr++)
clear_bit(vaddr, iounit->bmap);
spin_unlock_irqrestore(&iounit->lock, flags);
}
static void iounit_release_scsi_sgl(struct device *dev, struct scatterlist *sg, int sz)
{
struct iounit_struct *iounit = dev->archdata.iommu;
unsigned long flags;
unsigned long vaddr, len;
spin_lock_irqsave(&iounit->lock, flags);
while (sz != 0) {
--sz;
len = ((sg->dma_address & ~PAGE_MASK) + sg->length + (PAGE_SIZE-1)) >> PAGE_SHIFT;
vaddr = (sg->dma_address - IOUNIT_DMA_BASE) >> PAGE_SHIFT;
IOD(("iounit_release %08lx-%08lx\n", (long)vaddr, (long)len+vaddr));
for (len += vaddr; vaddr < len; vaddr++)
clear_bit(vaddr, iounit->bmap);
sg = sg_next(sg);
}
spin_unlock_irqrestore(&iounit->lock, flags);
}
#ifdef CONFIG_SBUS
static int iounit_map_dma_area(struct device *dev, dma_addr_t *pba, unsigned long va, unsigned long addr, int len)
{
struct iounit_struct *iounit = dev->archdata.iommu;
unsigned long page, end;
pgprot_t dvma_prot;
iopte_t __iomem *iopte;
*pba = addr;
dvma_prot = __pgprot(SRMMU_CACHE | SRMMU_ET_PTE | SRMMU_PRIV);
end = PAGE_ALIGN((addr + len));
while(addr < end) {
page = va;
{
pgd_t *pgdp;
pmd_t *pmdp;
pte_t *ptep;
long i;
pgdp = pgd_offset(&init_mm, addr);
pmdp = pmd_offset(pgdp, addr);
ptep = pte_offset_map(pmdp, addr);
set_pte(ptep, mk_pte(virt_to_page(page), dvma_prot));
i = ((addr - IOUNIT_DMA_BASE) >> PAGE_SHIFT);
iopte = iounit->page_table + i;
sbus_writel(iopte_val(MKIOPTE(__pa(page))), iopte);
}
addr += PAGE_SIZE;
va += PAGE_SIZE;
}
flush_cache_all();
flush_tlb_all();
return 0;
}
static void iounit_unmap_dma_area(struct device *dev, unsigned long addr, int len)
{
/* XXX Somebody please fill this in */
}
#endif
static const struct sparc32_dma_ops iounit_dma_ops = {
.get_scsi_one = iounit_get_scsi_one,
.get_scsi_sgl = iounit_get_scsi_sgl,
.release_scsi_one = iounit_release_scsi_one,
.release_scsi_sgl = iounit_release_scsi_sgl,
#ifdef CONFIG_SBUS
.map_dma_area = iounit_map_dma_area,
.unmap_dma_area = iounit_unmap_dma_area,
#endif
};
void __init ld_mmu_iounit(void)
{
sparc32_dma_ops = &iounit_dma_ops;
}