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-rw-r--r--arch/parisc/kernel/pci-dma.c472
1 files changed, 472 insertions, 0 deletions
diff --git a/arch/parisc/kernel/pci-dma.c b/arch/parisc/kernel/pci-dma.c
new file mode 100644
index 000000000..71ed5391f
--- /dev/null
+++ b/arch/parisc/kernel/pci-dma.c
@@ -0,0 +1,472 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+** PARISC 1.1 Dynamic DMA mapping support.
+** This implementation is for PA-RISC platforms that do not support
+** I/O TLBs (aka DMA address translation hardware).
+** See Documentation/core-api/dma-api-howto.rst for interface definitions.
+**
+** (c) Copyright 1999,2000 Hewlett-Packard Company
+** (c) Copyright 2000 Grant Grundler
+** (c) Copyright 2000 Philipp Rumpf <prumpf@tux.org>
+** (c) Copyright 2000 John Marvin
+**
+** "leveraged" from 2.3.47: arch/ia64/kernel/pci-dma.c.
+** (I assume it's from David Mosberger-Tang but there was no Copyright)
+**
+** AFAIK, all PA7100LC and PA7300LC platforms can use this code.
+**
+** - ggg
+*/
+
+#include <linux/init.h>
+#include <linux/gfp.h>
+#include <linux/mm.h>
+#include <linux/proc_fs.h>
+#include <linux/seq_file.h>
+#include <linux/string.h>
+#include <linux/types.h>
+#include <linux/dma-direct.h>
+#include <linux/dma-map-ops.h>
+
+#include <asm/cacheflush.h>
+#include <asm/dma.h> /* for DMA_CHUNK_SIZE */
+#include <asm/io.h>
+#include <asm/page.h> /* get_order */
+#include <linux/uaccess.h>
+#include <asm/tlbflush.h> /* for purge_tlb_*() macros */
+
+static struct proc_dir_entry * proc_gsc_root __read_mostly = NULL;
+static unsigned long pcxl_used_bytes __read_mostly;
+static unsigned long pcxl_used_pages __read_mostly;
+
+extern unsigned long pcxl_dma_start; /* Start of pcxl dma mapping area */
+static DEFINE_SPINLOCK(pcxl_res_lock);
+static char *pcxl_res_map;
+static int pcxl_res_hint;
+static int pcxl_res_size;
+
+#ifdef DEBUG_PCXL_RESOURCE
+#define DBG_RES(x...) printk(x)
+#else
+#define DBG_RES(x...)
+#endif
+
+
+/*
+** Dump a hex representation of the resource map.
+*/
+
+#ifdef DUMP_RESMAP
+static
+void dump_resmap(void)
+{
+ u_long *res_ptr = (unsigned long *)pcxl_res_map;
+ u_long i = 0;
+
+ printk("res_map: ");
+ for(; i < (pcxl_res_size / sizeof(unsigned long)); ++i, ++res_ptr)
+ printk("%08lx ", *res_ptr);
+
+ printk("\n");
+}
+#else
+static inline void dump_resmap(void) {;}
+#endif
+
+static inline int map_pte_uncached(pte_t * pte,
+ unsigned long vaddr,
+ unsigned long size, unsigned long *paddr_ptr)
+{
+ unsigned long end;
+ unsigned long orig_vaddr = vaddr;
+
+ vaddr &= ~PMD_MASK;
+ end = vaddr + size;
+ if (end > PMD_SIZE)
+ end = PMD_SIZE;
+ do {
+ unsigned long flags;
+
+ if (!pte_none(*pte))
+ printk(KERN_ERR "map_pte_uncached: page already exists\n");
+ purge_tlb_start(flags);
+ set_pte(pte, __mk_pte(*paddr_ptr, PAGE_KERNEL_UNC));
+ pdtlb(SR_KERNEL, orig_vaddr);
+ purge_tlb_end(flags);
+ vaddr += PAGE_SIZE;
+ orig_vaddr += PAGE_SIZE;
+ (*paddr_ptr) += PAGE_SIZE;
+ pte++;
+ } while (vaddr < end);
+ return 0;
+}
+
+static inline int map_pmd_uncached(pmd_t * pmd, unsigned long vaddr,
+ unsigned long size, unsigned long *paddr_ptr)
+{
+ unsigned long end;
+ unsigned long orig_vaddr = vaddr;
+
+ vaddr &= ~PGDIR_MASK;
+ end = vaddr + size;
+ if (end > PGDIR_SIZE)
+ end = PGDIR_SIZE;
+ do {
+ pte_t * pte = pte_alloc_kernel(pmd, vaddr);
+ if (!pte)
+ return -ENOMEM;
+ if (map_pte_uncached(pte, orig_vaddr, end - vaddr, paddr_ptr))
+ return -ENOMEM;
+ vaddr = (vaddr + PMD_SIZE) & PMD_MASK;
+ orig_vaddr += PMD_SIZE;
+ pmd++;
+ } while (vaddr < end);
+ return 0;
+}
+
+static inline int map_uncached_pages(unsigned long vaddr, unsigned long size,
+ unsigned long paddr)
+{
+ pgd_t * dir;
+ unsigned long end = vaddr + size;
+
+ dir = pgd_offset_k(vaddr);
+ do {
+ p4d_t *p4d;
+ pud_t *pud;
+ pmd_t *pmd;
+
+ p4d = p4d_offset(dir, vaddr);
+ pud = pud_offset(p4d, vaddr);
+ pmd = pmd_alloc(NULL, pud, vaddr);
+
+ if (!pmd)
+ return -ENOMEM;
+ if (map_pmd_uncached(pmd, vaddr, end - vaddr, &paddr))
+ return -ENOMEM;
+ vaddr = vaddr + PGDIR_SIZE;
+ dir++;
+ } while (vaddr && (vaddr < end));
+ return 0;
+}
+
+static inline void unmap_uncached_pte(pmd_t * pmd, unsigned long vaddr,
+ unsigned long size)
+{
+ pte_t * pte;
+ unsigned long end;
+ unsigned long orig_vaddr = vaddr;
+
+ if (pmd_none(*pmd))
+ return;
+ if (pmd_bad(*pmd)) {
+ pmd_ERROR(*pmd);
+ pmd_clear(pmd);
+ return;
+ }
+ pte = pte_offset_map(pmd, vaddr);
+ vaddr &= ~PMD_MASK;
+ end = vaddr + size;
+ if (end > PMD_SIZE)
+ end = PMD_SIZE;
+ do {
+ unsigned long flags;
+ pte_t page = *pte;
+
+ pte_clear(&init_mm, vaddr, pte);
+ purge_tlb_start(flags);
+ pdtlb(SR_KERNEL, orig_vaddr);
+ purge_tlb_end(flags);
+ vaddr += PAGE_SIZE;
+ orig_vaddr += PAGE_SIZE;
+ pte++;
+ if (pte_none(page) || pte_present(page))
+ continue;
+ printk(KERN_CRIT "Whee.. Swapped out page in kernel page table\n");
+ } while (vaddr < end);
+}
+
+static inline void unmap_uncached_pmd(pgd_t * dir, unsigned long vaddr,
+ unsigned long size)
+{
+ pmd_t * pmd;
+ unsigned long end;
+ unsigned long orig_vaddr = vaddr;
+
+ if (pgd_none(*dir))
+ return;
+ if (pgd_bad(*dir)) {
+ pgd_ERROR(*dir);
+ pgd_clear(dir);
+ return;
+ }
+ pmd = pmd_offset(pud_offset(p4d_offset(dir, vaddr), vaddr), vaddr);
+ vaddr &= ~PGDIR_MASK;
+ end = vaddr + size;
+ if (end > PGDIR_SIZE)
+ end = PGDIR_SIZE;
+ do {
+ unmap_uncached_pte(pmd, orig_vaddr, end - vaddr);
+ vaddr = (vaddr + PMD_SIZE) & PMD_MASK;
+ orig_vaddr += PMD_SIZE;
+ pmd++;
+ } while (vaddr < end);
+}
+
+static void unmap_uncached_pages(unsigned long vaddr, unsigned long size)
+{
+ pgd_t * dir;
+ unsigned long end = vaddr + size;
+
+ dir = pgd_offset_k(vaddr);
+ do {
+ unmap_uncached_pmd(dir, vaddr, end - vaddr);
+ vaddr = vaddr + PGDIR_SIZE;
+ dir++;
+ } while (vaddr && (vaddr < end));
+}
+
+#define PCXL_SEARCH_LOOP(idx, mask, size) \
+ for(; res_ptr < res_end; ++res_ptr) \
+ { \
+ if(0 == ((*res_ptr) & mask)) { \
+ *res_ptr |= mask; \
+ idx = (int)((u_long)res_ptr - (u_long)pcxl_res_map); \
+ pcxl_res_hint = idx + (size >> 3); \
+ goto resource_found; \
+ } \
+ }
+
+#define PCXL_FIND_FREE_MAPPING(idx, mask, size) { \
+ u##size *res_ptr = (u##size *)&(pcxl_res_map[pcxl_res_hint & ~((size >> 3) - 1)]); \
+ u##size *res_end = (u##size *)&pcxl_res_map[pcxl_res_size]; \
+ PCXL_SEARCH_LOOP(idx, mask, size); \
+ res_ptr = (u##size *)&pcxl_res_map[0]; \
+ PCXL_SEARCH_LOOP(idx, mask, size); \
+}
+
+unsigned long
+pcxl_alloc_range(size_t size)
+{
+ int res_idx;
+ u_long mask, flags;
+ unsigned int pages_needed = size >> PAGE_SHIFT;
+
+ mask = (u_long) -1L;
+ mask >>= BITS_PER_LONG - pages_needed;
+
+ DBG_RES("pcxl_alloc_range() size: %d pages_needed %d pages_mask 0x%08lx\n",
+ size, pages_needed, mask);
+
+ spin_lock_irqsave(&pcxl_res_lock, flags);
+
+ if(pages_needed <= 8) {
+ PCXL_FIND_FREE_MAPPING(res_idx, mask, 8);
+ } else if(pages_needed <= 16) {
+ PCXL_FIND_FREE_MAPPING(res_idx, mask, 16);
+ } else if(pages_needed <= 32) {
+ PCXL_FIND_FREE_MAPPING(res_idx, mask, 32);
+ } else {
+ panic("%s: pcxl_alloc_range() Too many pages to map.\n",
+ __FILE__);
+ }
+
+ dump_resmap();
+ panic("%s: pcxl_alloc_range() out of dma mapping resources\n",
+ __FILE__);
+
+resource_found:
+
+ DBG_RES("pcxl_alloc_range() res_idx %d mask 0x%08lx res_hint: %d\n",
+ res_idx, mask, pcxl_res_hint);
+
+ pcxl_used_pages += pages_needed;
+ pcxl_used_bytes += ((pages_needed >> 3) ? (pages_needed >> 3) : 1);
+
+ spin_unlock_irqrestore(&pcxl_res_lock, flags);
+
+ dump_resmap();
+
+ /*
+ ** return the corresponding vaddr in the pcxl dma map
+ */
+ return (pcxl_dma_start + (res_idx << (PAGE_SHIFT + 3)));
+}
+
+#define PCXL_FREE_MAPPINGS(idx, m, size) \
+ u##size *res_ptr = (u##size *)&(pcxl_res_map[(idx) + (((size >> 3) - 1) & (~((size >> 3) - 1)))]); \
+ /* BUG_ON((*res_ptr & m) != m); */ \
+ *res_ptr &= ~m;
+
+/*
+** clear bits in the pcxl resource map
+*/
+static void
+pcxl_free_range(unsigned long vaddr, size_t size)
+{
+ u_long mask, flags;
+ unsigned int res_idx = (vaddr - pcxl_dma_start) >> (PAGE_SHIFT + 3);
+ unsigned int pages_mapped = size >> PAGE_SHIFT;
+
+ mask = (u_long) -1L;
+ mask >>= BITS_PER_LONG - pages_mapped;
+
+ DBG_RES("pcxl_free_range() res_idx: %d size: %d pages_mapped %d mask 0x%08lx\n",
+ res_idx, size, pages_mapped, mask);
+
+ spin_lock_irqsave(&pcxl_res_lock, flags);
+
+ if(pages_mapped <= 8) {
+ PCXL_FREE_MAPPINGS(res_idx, mask, 8);
+ } else if(pages_mapped <= 16) {
+ PCXL_FREE_MAPPINGS(res_idx, mask, 16);
+ } else if(pages_mapped <= 32) {
+ PCXL_FREE_MAPPINGS(res_idx, mask, 32);
+ } else {
+ panic("%s: pcxl_free_range() Too many pages to unmap.\n",
+ __FILE__);
+ }
+
+ pcxl_used_pages -= (pages_mapped ? pages_mapped : 1);
+ pcxl_used_bytes -= ((pages_mapped >> 3) ? (pages_mapped >> 3) : 1);
+
+ spin_unlock_irqrestore(&pcxl_res_lock, flags);
+
+ dump_resmap();
+}
+
+static int __maybe_unused proc_pcxl_dma_show(struct seq_file *m, void *v)
+{
+#if 0
+ u_long i = 0;
+ unsigned long *res_ptr = (u_long *)pcxl_res_map;
+#endif
+ unsigned long total_pages = pcxl_res_size << 3; /* 8 bits per byte */
+
+ seq_printf(m, "\nDMA Mapping Area size : %d bytes (%ld pages)\n",
+ PCXL_DMA_MAP_SIZE, total_pages);
+
+ seq_printf(m, "Resource bitmap : %d bytes\n", pcxl_res_size);
+
+ seq_puts(m, " total: free: used: % used:\n");
+ seq_printf(m, "blocks %8d %8ld %8ld %8ld%%\n", pcxl_res_size,
+ pcxl_res_size - pcxl_used_bytes, pcxl_used_bytes,
+ (pcxl_used_bytes * 100) / pcxl_res_size);
+
+ seq_printf(m, "pages %8ld %8ld %8ld %8ld%%\n", total_pages,
+ total_pages - pcxl_used_pages, pcxl_used_pages,
+ (pcxl_used_pages * 100 / total_pages));
+
+#if 0
+ seq_puts(m, "\nResource bitmap:");
+
+ for(; i < (pcxl_res_size / sizeof(u_long)); ++i, ++res_ptr) {
+ if ((i & 7) == 0)
+ seq_puts(m,"\n ");
+ seq_printf(m, "%s %08lx", buf, *res_ptr);
+ }
+#endif
+ seq_putc(m, '\n');
+ return 0;
+}
+
+static int __init
+pcxl_dma_init(void)
+{
+ if (pcxl_dma_start == 0)
+ return 0;
+
+ pcxl_res_size = PCXL_DMA_MAP_SIZE >> (PAGE_SHIFT + 3);
+ pcxl_res_hint = 0;
+ pcxl_res_map = (char *)__get_free_pages(GFP_KERNEL,
+ get_order(pcxl_res_size));
+ memset(pcxl_res_map, 0, pcxl_res_size);
+ proc_gsc_root = proc_mkdir("gsc", NULL);
+ if (!proc_gsc_root)
+ printk(KERN_WARNING
+ "pcxl_dma_init: Unable to create gsc /proc dir entry\n");
+ else {
+ struct proc_dir_entry* ent;
+ ent = proc_create_single("pcxl_dma", 0, proc_gsc_root,
+ proc_pcxl_dma_show);
+ if (!ent)
+ printk(KERN_WARNING
+ "pci-dma.c: Unable to create pcxl_dma /proc entry.\n");
+ }
+ return 0;
+}
+
+__initcall(pcxl_dma_init);
+
+void *arch_dma_alloc(struct device *dev, size_t size,
+ dma_addr_t *dma_handle, gfp_t gfp, unsigned long attrs)
+{
+ unsigned long vaddr;
+ unsigned long paddr;
+ int order;
+
+ if (boot_cpu_data.cpu_type != pcxl2 && boot_cpu_data.cpu_type != pcxl)
+ return NULL;
+
+ order = get_order(size);
+ size = 1 << (order + PAGE_SHIFT);
+ vaddr = pcxl_alloc_range(size);
+ paddr = __get_free_pages(gfp | __GFP_ZERO, order);
+ flush_kernel_dcache_range(paddr, size);
+ paddr = __pa(paddr);
+ map_uncached_pages(vaddr, size, paddr);
+ *dma_handle = (dma_addr_t) paddr;
+
+#if 0
+/* This probably isn't needed to support EISA cards.
+** ISA cards will certainly only support 24-bit DMA addressing.
+** Not clear if we can, want, or need to support ISA.
+*/
+ if (!dev || *dev->coherent_dma_mask < 0xffffffff)
+ gfp |= GFP_DMA;
+#endif
+ return (void *)vaddr;
+}
+
+void arch_dma_free(struct device *dev, size_t size, void *vaddr,
+ dma_addr_t dma_handle, unsigned long attrs)
+{
+ int order = get_order(size);
+
+ WARN_ON_ONCE(boot_cpu_data.cpu_type != pcxl2 &&
+ boot_cpu_data.cpu_type != pcxl);
+
+ size = 1 << (order + PAGE_SHIFT);
+ unmap_uncached_pages((unsigned long)vaddr, size);
+ pcxl_free_range((unsigned long)vaddr, size);
+
+ free_pages((unsigned long)__va(dma_handle), order);
+}
+
+void arch_sync_dma_for_device(phys_addr_t paddr, size_t size,
+ enum dma_data_direction dir)
+{
+ /*
+ * fdc: The data cache line is written back to memory, if and only if
+ * it is dirty, and then invalidated from the data cache.
+ */
+ flush_kernel_dcache_range((unsigned long)phys_to_virt(paddr), size);
+}
+
+void arch_sync_dma_for_cpu(phys_addr_t paddr, size_t size,
+ enum dma_data_direction dir)
+{
+ unsigned long addr = (unsigned long) phys_to_virt(paddr);
+
+ switch (dir) {
+ case DMA_TO_DEVICE:
+ case DMA_BIDIRECTIONAL:
+ flush_kernel_dcache_range(addr, size);
+ return;
+ case DMA_FROM_DEVICE:
+ purge_kernel_dcache_range_asm(addr, addr + size);
+ return;
+ default:
+ BUG();
+ }
+}
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