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author | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-04-11 08:27:49 +0000 |
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committer | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-04-11 08:27:49 +0000 |
commit | ace9429bb58fd418f0c81d4c2835699bddf6bde6 (patch) | |
tree | b2d64bc10158fdd5497876388cd68142ca374ed3 /arch/sparc/mm/iommu.c | |
parent | Initial commit. (diff) | |
download | linux-ace9429bb58fd418f0c81d4c2835699bddf6bde6.tar.xz linux-ace9429bb58fd418f0c81d4c2835699bddf6bde6.zip |
Adding upstream version 6.6.15.upstream/6.6.15
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to '')
-rw-r--r-- | arch/sparc/mm/iommu.c | 455 |
1 files changed, 455 insertions, 0 deletions
diff --git a/arch/sparc/mm/iommu.c b/arch/sparc/mm/iommu.c new file mode 100644 index 0000000000..5a5080db80 --- /dev/null +++ b/arch/sparc/mm/iommu.c @@ -0,0 +1,455 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * iommu.c: IOMMU specific routines for memory management. + * + * Copyright (C) 1995 David S. Miller (davem@caip.rutgers.edu) + * Copyright (C) 1995,2002 Pete Zaitcev (zaitcev@yahoo.com) + * Copyright (C) 1996 Eddie C. Dost (ecd@skynet.be) + * Copyright (C) 1997,1998 Jakub Jelinek (jj@sunsite.mff.cuni.cz) + */ + +#include <linux/kernel.h> +#include <linux/init.h> +#include <linux/mm.h> +#include <linux/slab.h> +#include <linux/dma-map-ops.h> +#include <linux/of.h> +#include <linux/of_platform.h> +#include <linux/platform_device.h> + +#include <asm/io.h> +#include <asm/mxcc.h> +#include <asm/mbus.h> +#include <asm/cacheflush.h> +#include <asm/tlbflush.h> +#include <asm/bitext.h> +#include <asm/iommu.h> +#include <asm/dma.h> + +#include "mm_32.h" + +/* + * This can be sized dynamically, but we will do this + * only when we have a guidance about actual I/O pressures. + */ +#define IOMMU_RNGE IOMMU_RNGE_256MB +#define IOMMU_START 0xF0000000 +#define IOMMU_WINSIZE (256*1024*1024U) +#define IOMMU_NPTES (IOMMU_WINSIZE/PAGE_SIZE) /* 64K PTEs, 256KB */ +#define IOMMU_ORDER 6 /* 4096 * (1<<6) */ + +static int viking_flush; +/* viking.S */ +extern void viking_flush_page(unsigned long page); +extern void viking_mxcc_flush_page(unsigned long page); + +/* + * Values precomputed according to CPU type. + */ +static unsigned int ioperm_noc; /* Consistent mapping iopte flags */ +static pgprot_t dvma_prot; /* Consistent mapping pte flags */ + +#define IOPERM (IOPTE_CACHE | IOPTE_WRITE | IOPTE_VALID) +#define MKIOPTE(pfn, perm) (((((pfn)<<8) & IOPTE_PAGE) | (perm)) & ~IOPTE_WAZ) + +static const struct dma_map_ops sbus_iommu_dma_gflush_ops; +static const struct dma_map_ops sbus_iommu_dma_pflush_ops; + +static void __init sbus_iommu_init(struct platform_device *op) +{ + struct iommu_struct *iommu; + unsigned int impl, vers; + unsigned long *bitmap; + unsigned long control; + unsigned long base; + unsigned long tmp; + + iommu = kmalloc(sizeof(struct iommu_struct), GFP_KERNEL); + if (!iommu) { + prom_printf("Unable to allocate iommu structure\n"); + prom_halt(); + } + + iommu->regs = of_ioremap(&op->resource[0], 0, PAGE_SIZE * 3, + "iommu_regs"); + if (!iommu->regs) { + prom_printf("Cannot map IOMMU registers\n"); + prom_halt(); + } + + control = sbus_readl(&iommu->regs->control); + impl = (control & IOMMU_CTRL_IMPL) >> 28; + vers = (control & IOMMU_CTRL_VERS) >> 24; + control &= ~(IOMMU_CTRL_RNGE); + control |= (IOMMU_RNGE_256MB | IOMMU_CTRL_ENAB); + sbus_writel(control, &iommu->regs->control); + + iommu_invalidate(iommu->regs); + iommu->start = IOMMU_START; + iommu->end = 0xffffffff; + + /* Allocate IOMMU page table */ + /* Stupid alignment constraints give me a headache. + We need 256K or 512K or 1M or 2M area aligned to + its size and current gfp will fortunately give + it to us. */ + tmp = __get_free_pages(GFP_KERNEL, IOMMU_ORDER); + if (!tmp) { + prom_printf("Unable to allocate iommu table [0x%lx]\n", + IOMMU_NPTES * sizeof(iopte_t)); + prom_halt(); + } + iommu->page_table = (iopte_t *)tmp; + + /* Initialize new table. */ + memset(iommu->page_table, 0, IOMMU_NPTES*sizeof(iopte_t)); + flush_cache_all(); + flush_tlb_all(); + + base = __pa((unsigned long)iommu->page_table) >> 4; + sbus_writel(base, &iommu->regs->base); + iommu_invalidate(iommu->regs); + + bitmap = kmalloc(IOMMU_NPTES>>3, GFP_KERNEL); + if (!bitmap) { + prom_printf("Unable to allocate iommu bitmap [%d]\n", + (int)(IOMMU_NPTES>>3)); + prom_halt(); + } + bit_map_init(&iommu->usemap, bitmap, IOMMU_NPTES); + /* To be coherent on HyperSparc, the page color of DVMA + * and physical addresses must match. + */ + if (srmmu_modtype == HyperSparc) + iommu->usemap.num_colors = vac_cache_size >> PAGE_SHIFT; + else + iommu->usemap.num_colors = 1; + + printk(KERN_INFO "IOMMU: impl %d vers %d table 0x%p[%d B] map [%d b]\n", + impl, vers, iommu->page_table, + (int)(IOMMU_NPTES*sizeof(iopte_t)), (int)IOMMU_NPTES); + + op->dev.archdata.iommu = iommu; + + if (flush_page_for_dma_global) + op->dev.dma_ops = &sbus_iommu_dma_gflush_ops; + else + op->dev.dma_ops = &sbus_iommu_dma_pflush_ops; +} + +static int __init iommu_init(void) +{ + struct device_node *dp; + + for_each_node_by_name(dp, "iommu") { + struct platform_device *op = of_find_device_by_node(dp); + + sbus_iommu_init(op); + of_propagate_archdata(op); + } + + return 0; +} + +subsys_initcall(iommu_init); + +/* Flush the iotlb entries to ram. */ +/* This could be better if we didn't have to flush whole pages. */ +static void iommu_flush_iotlb(iopte_t *iopte, unsigned int niopte) +{ + unsigned long start; + unsigned long end; + + start = (unsigned long)iopte; + end = PAGE_ALIGN(start + niopte*sizeof(iopte_t)); + start &= PAGE_MASK; + if (viking_mxcc_present) { + while(start < end) { + viking_mxcc_flush_page(start); + start += PAGE_SIZE; + } + } else if (viking_flush) { + while(start < end) { + viking_flush_page(start); + start += PAGE_SIZE; + } + } else { + while(start < end) { + __flush_page_to_ram(start); + start += PAGE_SIZE; + } + } +} + +static dma_addr_t __sbus_iommu_map_page(struct device *dev, struct page *page, + unsigned long offset, size_t len, bool per_page_flush) +{ + struct iommu_struct *iommu = dev->archdata.iommu; + phys_addr_t paddr = page_to_phys(page) + offset; + unsigned long off = paddr & ~PAGE_MASK; + unsigned long npages = (off + len + PAGE_SIZE - 1) >> PAGE_SHIFT; + unsigned long pfn = __phys_to_pfn(paddr); + unsigned int busa, busa0; + iopte_t *iopte, *iopte0; + int ioptex, i; + + /* XXX So what is maxphys for us and how do drivers know it? */ + if (!len || len > 256 * 1024) + return DMA_MAPPING_ERROR; + + /* + * We expect unmapped highmem pages to be not in the cache. + * XXX Is this a good assumption? + * XXX What if someone else unmaps it here and races us? + */ + if (per_page_flush && !PageHighMem(page)) { + unsigned long vaddr, p; + + vaddr = (unsigned long)page_address(page) + offset; + for (p = vaddr & PAGE_MASK; p < vaddr + len; p += PAGE_SIZE) + flush_page_for_dma(p); + } + + /* page color = pfn of page */ + ioptex = bit_map_string_get(&iommu->usemap, npages, pfn); + if (ioptex < 0) + panic("iommu out"); + busa0 = iommu->start + (ioptex << PAGE_SHIFT); + iopte0 = &iommu->page_table[ioptex]; + + busa = busa0; + iopte = iopte0; + for (i = 0; i < npages; i++) { + iopte_val(*iopte) = MKIOPTE(pfn, IOPERM); + iommu_invalidate_page(iommu->regs, busa); + busa += PAGE_SIZE; + iopte++; + pfn++; + } + + iommu_flush_iotlb(iopte0, npages); + return busa0 + off; +} + +static dma_addr_t sbus_iommu_map_page_gflush(struct device *dev, + struct page *page, unsigned long offset, size_t len, + enum dma_data_direction dir, unsigned long attrs) +{ + flush_page_for_dma(0); + return __sbus_iommu_map_page(dev, page, offset, len, false); +} + +static dma_addr_t sbus_iommu_map_page_pflush(struct device *dev, + struct page *page, unsigned long offset, size_t len, + enum dma_data_direction dir, unsigned long attrs) +{ + return __sbus_iommu_map_page(dev, page, offset, len, true); +} + +static int __sbus_iommu_map_sg(struct device *dev, struct scatterlist *sgl, + int nents, enum dma_data_direction dir, unsigned long attrs, + bool per_page_flush) +{ + struct scatterlist *sg; + int j; + + for_each_sg(sgl, sg, nents, j) { + sg->dma_address =__sbus_iommu_map_page(dev, sg_page(sg), + sg->offset, sg->length, per_page_flush); + if (sg->dma_address == DMA_MAPPING_ERROR) + return -EIO; + sg->dma_length = sg->length; + } + + return nents; +} + +static int sbus_iommu_map_sg_gflush(struct device *dev, struct scatterlist *sgl, + int nents, enum dma_data_direction dir, unsigned long attrs) +{ + flush_page_for_dma(0); + return __sbus_iommu_map_sg(dev, sgl, nents, dir, attrs, false); +} + +static int sbus_iommu_map_sg_pflush(struct device *dev, struct scatterlist *sgl, + int nents, enum dma_data_direction dir, unsigned long attrs) +{ + return __sbus_iommu_map_sg(dev, sgl, nents, dir, attrs, true); +} + +static void sbus_iommu_unmap_page(struct device *dev, dma_addr_t dma_addr, + size_t len, enum dma_data_direction dir, unsigned long attrs) +{ + struct iommu_struct *iommu = dev->archdata.iommu; + unsigned int busa = dma_addr & PAGE_MASK; + unsigned long off = dma_addr & ~PAGE_MASK; + unsigned int npages = (off + len + PAGE_SIZE-1) >> PAGE_SHIFT; + unsigned int ioptex = (busa - iommu->start) >> PAGE_SHIFT; + unsigned int i; + + BUG_ON(busa < iommu->start); + for (i = 0; i < npages; i++) { + iopte_val(iommu->page_table[ioptex + i]) = 0; + iommu_invalidate_page(iommu->regs, busa); + busa += PAGE_SIZE; + } + bit_map_clear(&iommu->usemap, ioptex, npages); +} + +static void sbus_iommu_unmap_sg(struct device *dev, struct scatterlist *sgl, + int nents, enum dma_data_direction dir, unsigned long attrs) +{ + struct scatterlist *sg; + int i; + + for_each_sg(sgl, sg, nents, i) { + sbus_iommu_unmap_page(dev, sg->dma_address, sg->length, dir, + attrs); + sg->dma_address = 0x21212121; + } +} + +#ifdef CONFIG_SBUS +static void *sbus_iommu_alloc(struct device *dev, size_t len, + dma_addr_t *dma_handle, gfp_t gfp, unsigned long attrs) +{ + struct iommu_struct *iommu = dev->archdata.iommu; + unsigned long va, addr, page, end, ret; + iopte_t *iopte = iommu->page_table; + iopte_t *first; + int ioptex; + + /* XXX So what is maxphys for us and how do drivers know it? */ + if (!len || len > 256 * 1024) + return NULL; + + len = PAGE_ALIGN(len); + va = __get_free_pages(gfp | __GFP_ZERO, get_order(len)); + if (va == 0) + return NULL; + + addr = ret = sparc_dma_alloc_resource(dev, len); + if (!addr) + goto out_free_pages; + + BUG_ON((va & ~PAGE_MASK) != 0); + BUG_ON((addr & ~PAGE_MASK) != 0); + BUG_ON((len & ~PAGE_MASK) != 0); + + /* page color = physical address */ + ioptex = bit_map_string_get(&iommu->usemap, len >> PAGE_SHIFT, + addr >> PAGE_SHIFT); + if (ioptex < 0) + panic("iommu out"); + + iopte += ioptex; + first = iopte; + end = addr + len; + while(addr < end) { + page = va; + { + pmd_t *pmdp; + pte_t *ptep; + + if (viking_mxcc_present) + viking_mxcc_flush_page(page); + else if (viking_flush) + viking_flush_page(page); + else + __flush_page_to_ram(page); + + pmdp = pmd_off_k(addr); + ptep = pte_offset_kernel(pmdp, addr); + + set_pte(ptep, mk_pte(virt_to_page(page), dvma_prot)); + } + iopte_val(*iopte++) = + MKIOPTE(page_to_pfn(virt_to_page(page)), ioperm_noc); + addr += PAGE_SIZE; + va += PAGE_SIZE; + } + /* P3: why do we need this? + * + * DAVEM: Because there are several aspects, none of which + * are handled by a single interface. Some cpus are + * completely not I/O DMA coherent, and some have + * virtually indexed caches. The driver DMA flushing + * methods handle the former case, but here during + * IOMMU page table modifications, and usage of non-cacheable + * cpu mappings of pages potentially in the cpu caches, we have + * to handle the latter case as well. + */ + flush_cache_all(); + iommu_flush_iotlb(first, len >> PAGE_SHIFT); + flush_tlb_all(); + iommu_invalidate(iommu->regs); + + *dma_handle = iommu->start + (ioptex << PAGE_SHIFT); + return (void *)ret; + +out_free_pages: + free_pages(va, get_order(len)); + return NULL; +} + +static void sbus_iommu_free(struct device *dev, size_t len, void *cpu_addr, + dma_addr_t busa, unsigned long attrs) +{ + struct iommu_struct *iommu = dev->archdata.iommu; + iopte_t *iopte = iommu->page_table; + struct page *page = virt_to_page(cpu_addr); + int ioptex = (busa - iommu->start) >> PAGE_SHIFT; + unsigned long end; + + if (!sparc_dma_free_resource(cpu_addr, len)) + return; + + BUG_ON((busa & ~PAGE_MASK) != 0); + BUG_ON((len & ~PAGE_MASK) != 0); + + iopte += ioptex; + end = busa + len; + while (busa < end) { + iopte_val(*iopte++) = 0; + busa += PAGE_SIZE; + } + flush_tlb_all(); + iommu_invalidate(iommu->regs); + bit_map_clear(&iommu->usemap, ioptex, len >> PAGE_SHIFT); + + __free_pages(page, get_order(len)); +} +#endif + +static const struct dma_map_ops sbus_iommu_dma_gflush_ops = { +#ifdef CONFIG_SBUS + .alloc = sbus_iommu_alloc, + .free = sbus_iommu_free, +#endif + .map_page = sbus_iommu_map_page_gflush, + .unmap_page = sbus_iommu_unmap_page, + .map_sg = sbus_iommu_map_sg_gflush, + .unmap_sg = sbus_iommu_unmap_sg, +}; + +static const struct dma_map_ops sbus_iommu_dma_pflush_ops = { +#ifdef CONFIG_SBUS + .alloc = sbus_iommu_alloc, + .free = sbus_iommu_free, +#endif + .map_page = sbus_iommu_map_page_pflush, + .unmap_page = sbus_iommu_unmap_page, + .map_sg = sbus_iommu_map_sg_pflush, + .unmap_sg = sbus_iommu_unmap_sg, +}; + +void __init ld_mmu_iommu(void) +{ + if (viking_mxcc_present || srmmu_modtype == HyperSparc) { + dvma_prot = __pgprot(SRMMU_CACHE | SRMMU_ET_PTE | SRMMU_PRIV); + ioperm_noc = IOPTE_CACHE | IOPTE_WRITE | IOPTE_VALID; + } else { + dvma_prot = __pgprot(SRMMU_ET_PTE | SRMMU_PRIV); + ioperm_noc = IOPTE_WRITE | IOPTE_VALID; + } +} |