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Diffstat (limited to '')
| -rw-r--r-- | arch/sparc/mm/io-unit.c | 263 |
1 files changed, 263 insertions, 0 deletions
diff --git a/arch/sparc/mm/io-unit.c b/arch/sparc/mm/io-unit.c new file mode 100644 index 000000000..c8cb27d3e --- /dev/null +++ b/arch/sparc/mm/io-unit.c @@ -0,0 +1,263 @@ +// 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; +} |