1 // SPDX-License-Identifier: GPL-2.0 2 /* 3 * io-unit.c: IO-UNIT specific routines for memory management. 4 * 5 * Copyright (C) 1997,1998 Jakub Jelinek (jj@sunsite.mff.cuni.cz) 6 */ 7 8 #include <linux/kernel.h> 9 #include <linux/init.h> 10 #include <linux/slab.h> 11 #include <linux/spinlock.h> 12 #include <linux/mm.h> 13 #include <linux/highmem.h> /* pte_offset_map => kmap_atomic */ 14 #include <linux/bitops.h> 15 #include <linux/scatterlist.h> 16 #include <linux/of.h> 17 #include <linux/of_device.h> 18 19 #include <asm/pgalloc.h> 20 #include <asm/pgtable.h> 21 #include <asm/io.h> 22 #include <asm/io-unit.h> 23 #include <asm/mxcc.h> 24 #include <asm/cacheflush.h> 25 #include <asm/tlbflush.h> 26 #include <asm/dma.h> 27 #include <asm/oplib.h> 28 29 #include "mm_32.h" 30 31 /* #define IOUNIT_DEBUG */ 32 #ifdef IOUNIT_DEBUG 33 #define IOD(x) printk(x) 34 #else 35 #define IOD(x) do { } while (0) 36 #endif 37 38 #define IOPERM (IOUPTE_CACHE | IOUPTE_WRITE | IOUPTE_VALID) 39 #define MKIOPTE(phys) __iopte((((phys)>>4) & IOUPTE_PAGE) | IOPERM) 40 41 static void __init iounit_iommu_init(struct platform_device *op) 42 { 43 struct iounit_struct *iounit; 44 iopte_t __iomem *xpt; 45 iopte_t __iomem *xptend; 46 47 iounit = kzalloc(sizeof(struct iounit_struct), GFP_ATOMIC); 48 if (!iounit) { 49 prom_printf("SUN4D: Cannot alloc iounit, halting.\n"); 50 prom_halt(); 51 } 52 53 iounit->limit[0] = IOUNIT_BMAP1_START; 54 iounit->limit[1] = IOUNIT_BMAP2_START; 55 iounit->limit[2] = IOUNIT_BMAPM_START; 56 iounit->limit[3] = IOUNIT_BMAPM_END; 57 iounit->rotor[1] = IOUNIT_BMAP2_START; 58 iounit->rotor[2] = IOUNIT_BMAPM_START; 59 60 xpt = of_ioremap(&op->resource[2], 0, PAGE_SIZE * 16, "XPT"); 61 if (!xpt) { 62 prom_printf("SUN4D: Cannot map External Page Table."); 63 prom_halt(); 64 } 65 66 op->dev.archdata.iommu = iounit; 67 iounit->page_table = xpt; 68 spin_lock_init(&iounit->lock); 69 70 xptend = iounit->page_table + (16 * PAGE_SIZE) / sizeof(iopte_t); 71 for (; xpt < xptend; xpt++) 72 sbus_writel(0, xpt); 73 } 74 75 static int __init iounit_init(void) 76 { 77 extern void sun4d_init_sbi_irq(void); 78 struct device_node *dp; 79 80 for_each_node_by_name(dp, "sbi") { 81 struct platform_device *op = of_find_device_by_node(dp); 82 83 iounit_iommu_init(op); 84 of_propagate_archdata(op); 85 } 86 87 sun4d_init_sbi_irq(); 88 89 return 0; 90 } 91 92 subsys_initcall(iounit_init); 93 94 /* One has to hold iounit->lock to call this */ 95 static unsigned long iounit_get_area(struct iounit_struct *iounit, unsigned long vaddr, int size) 96 { 97 int i, j, k, npages; 98 unsigned long rotor, scan, limit; 99 iopte_t iopte; 100 101 npages = ((vaddr & ~PAGE_MASK) + size + (PAGE_SIZE-1)) >> PAGE_SHIFT; 102 103 /* A tiny bit of magic ingredience :) */ 104 switch (npages) { 105 case 1: i = 0x0231; break; 106 case 2: i = 0x0132; break; 107 default: i = 0x0213; break; 108 } 109 110 IOD(("iounit_get_area(%08lx,%d[%d])=", vaddr, size, npages)); 111 112 next: j = (i & 15); 113 rotor = iounit->rotor[j - 1]; 114 limit = iounit->limit[j]; 115 scan = rotor; 116 nexti: scan = find_next_zero_bit(iounit->bmap, limit, scan); 117 if (scan + npages > limit) { 118 if (limit != rotor) { 119 limit = rotor; 120 scan = iounit->limit[j - 1]; 121 goto nexti; 122 } 123 i >>= 4; 124 if (!(i & 15)) 125 panic("iounit_get_area: Couldn't find free iopte slots for (%08lx,%d)\n", vaddr, size); 126 goto next; 127 } 128 for (k = 1, scan++; k < npages; k++) 129 if (test_bit(scan++, iounit->bmap)) 130 goto nexti; 131 iounit->rotor[j - 1] = (scan < limit) ? scan : iounit->limit[j - 1]; 132 scan -= npages; 133 iopte = MKIOPTE(__pa(vaddr & PAGE_MASK)); 134 vaddr = IOUNIT_DMA_BASE + (scan << PAGE_SHIFT) + (vaddr & ~PAGE_MASK); 135 for (k = 0; k < npages; k++, iopte = __iopte(iopte_val(iopte) + 0x100), scan++) { 136 set_bit(scan, iounit->bmap); 137 sbus_writel(iopte_val(iopte), &iounit->page_table[scan]); 138 } 139 IOD(("%08lx\n", vaddr)); 140 return vaddr; 141 } 142 143 static __u32 iounit_get_scsi_one(struct device *dev, char *vaddr, unsigned long len) 144 { 145 struct iounit_struct *iounit = dev->archdata.iommu; 146 unsigned long ret, flags; 147 148 spin_lock_irqsave(&iounit->lock, flags); 149 ret = iounit_get_area(iounit, (unsigned long)vaddr, len); 150 spin_unlock_irqrestore(&iounit->lock, flags); 151 return ret; 152 } 153 154 static void iounit_get_scsi_sgl(struct device *dev, struct scatterlist *sg, int sz) 155 { 156 struct iounit_struct *iounit = dev->archdata.iommu; 157 unsigned long flags; 158 159 /* FIXME: Cache some resolved pages - often several sg entries are to the same page */ 160 spin_lock_irqsave(&iounit->lock, flags); 161 while (sz != 0) { 162 --sz; 163 sg->dma_address = iounit_get_area(iounit, (unsigned long) sg_virt(sg), sg->length); 164 sg->dma_length = sg->length; 165 sg = sg_next(sg); 166 } 167 spin_unlock_irqrestore(&iounit->lock, flags); 168 } 169 170 static void iounit_release_scsi_one(struct device *dev, __u32 vaddr, unsigned long len) 171 { 172 struct iounit_struct *iounit = dev->archdata.iommu; 173 unsigned long flags; 174 175 spin_lock_irqsave(&iounit->lock, flags); 176 len = ((vaddr & ~PAGE_MASK) + len + (PAGE_SIZE-1)) >> PAGE_SHIFT; 177 vaddr = (vaddr - IOUNIT_DMA_BASE) >> PAGE_SHIFT; 178 IOD(("iounit_release %08lx-%08lx\n", (long)vaddr, (long)len+vaddr)); 179 for (len += vaddr; vaddr < len; vaddr++) 180 clear_bit(vaddr, iounit->bmap); 181 spin_unlock_irqrestore(&iounit->lock, flags); 182 } 183 184 static void iounit_release_scsi_sgl(struct device *dev, struct scatterlist *sg, int sz) 185 { 186 struct iounit_struct *iounit = dev->archdata.iommu; 187 unsigned long flags; 188 unsigned long vaddr, len; 189 190 spin_lock_irqsave(&iounit->lock, flags); 191 while (sz != 0) { 192 --sz; 193 len = ((sg->dma_address & ~PAGE_MASK) + sg->length + (PAGE_SIZE-1)) >> PAGE_SHIFT; 194 vaddr = (sg->dma_address - IOUNIT_DMA_BASE) >> PAGE_SHIFT; 195 IOD(("iounit_release %08lx-%08lx\n", (long)vaddr, (long)len+vaddr)); 196 for (len += vaddr; vaddr < len; vaddr++) 197 clear_bit(vaddr, iounit->bmap); 198 sg = sg_next(sg); 199 } 200 spin_unlock_irqrestore(&iounit->lock, flags); 201 } 202 203 #ifdef CONFIG_SBUS 204 static int iounit_map_dma_area(struct device *dev, dma_addr_t *pba, unsigned long va, unsigned long addr, int len) 205 { 206 struct iounit_struct *iounit = dev->archdata.iommu; 207 unsigned long page, end; 208 pgprot_t dvma_prot; 209 iopte_t __iomem *iopte; 210 211 *pba = addr; 212 213 dvma_prot = __pgprot(SRMMU_CACHE | SRMMU_ET_PTE | SRMMU_PRIV); 214 end = PAGE_ALIGN((addr + len)); 215 while(addr < end) { 216 page = va; 217 { 218 pgd_t *pgdp; 219 pmd_t *pmdp; 220 pte_t *ptep; 221 long i; 222 223 pgdp = pgd_offset(&init_mm, addr); 224 pmdp = pmd_offset(pgdp, addr); 225 ptep = pte_offset_map(pmdp, addr); 226 227 set_pte(ptep, mk_pte(virt_to_page(page), dvma_prot)); 228 229 i = ((addr - IOUNIT_DMA_BASE) >> PAGE_SHIFT); 230 231 iopte = iounit->page_table + i; 232 sbus_writel(iopte_val(MKIOPTE(__pa(page))), iopte); 233 } 234 addr += PAGE_SIZE; 235 va += PAGE_SIZE; 236 } 237 flush_cache_all(); 238 flush_tlb_all(); 239 240 return 0; 241 } 242 243 static void iounit_unmap_dma_area(struct device *dev, unsigned long addr, int len) 244 { 245 /* XXX Somebody please fill this in */ 246 } 247 #endif 248 249 static const struct sparc32_dma_ops iounit_dma_ops = { 250 .get_scsi_one = iounit_get_scsi_one, 251 .get_scsi_sgl = iounit_get_scsi_sgl, 252 .release_scsi_one = iounit_release_scsi_one, 253 .release_scsi_sgl = iounit_release_scsi_sgl, 254 #ifdef CONFIG_SBUS 255 .map_dma_area = iounit_map_dma_area, 256 .unmap_dma_area = iounit_unmap_dma_area, 257 #endif 258 }; 259 260 void __init ld_mmu_iounit(void) 261 { 262 sparc32_dma_ops = &iounit_dma_ops; 263 } 264