diff options
Diffstat (limited to 'drivers/staging/tidspbridge/core/dsp-mmu.c')
| -rw-r--r-- | drivers/staging/tidspbridge/core/dsp-mmu.c | 317 |
1 files changed, 317 insertions, 0 deletions
diff --git a/drivers/staging/tidspbridge/core/dsp-mmu.c b/drivers/staging/tidspbridge/core/dsp-mmu.c new file mode 100644 index 0000000..983c95a --- /dev/null +++ b/drivers/staging/tidspbridge/core/dsp-mmu.c @@ -0,0 +1,317 @@ +/* + * dsp-mmu.c + * + * DSP-BIOS Bridge driver support functions for TI OMAP processors. + * + * DSP iommu. + * + * Copyright (C) 2010 Texas Instruments, Inc. + * + * This package is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License version 2 as + * published by the Free Software Foundation. + * + * THIS PACKAGE IS PROVIDED ``AS IS'' AND WITHOUT ANY EXPRESS OR + * IMPLIED WARRANTIES, INCLUDING, WITHOUT LIMITATION, THE IMPLIED + * WARRANTIES OF MERCHANTIBILITY AND FITNESS FOR A PARTICULAR PURPOSE. + */ + +#include <dspbridge/host_os.h> +#include <plat/dmtimer.h> +#include <dspbridge/dbdefs.h> +#include <dspbridge/dev.h> +#include <dspbridge/io_sm.h> +#include <dspbridge/dspdeh.h> +#include "_tiomap.h" + +#include <dspbridge/dsp-mmu.h> + +#define MMU_CNTL_TWL_EN (1 << 2) + +static struct tasklet_struct mmu_tasklet; + +#ifdef CONFIG_TIDSPBRIDGE_BACKTRACE +static void mmu_fault_print_stack(struct bridge_dev_context *dev_context) +{ + void *dummy_addr; + u32 fa, tmp; + struct iotlb_entry e; + struct iommu *mmu = dev_context->dsp_mmu; + dummy_addr = (void *)__get_free_page(GFP_ATOMIC); + + /* + * Before acking the MMU fault, let's make sure MMU can only + * access entry #0. Then add a new entry so that the DSP OS + * can continue in order to dump the stack. + */ + tmp = iommu_read_reg(mmu, MMU_CNTL); + tmp &= ~MMU_CNTL_TWL_EN; + iommu_write_reg(mmu, tmp, MMU_CNTL); + fa = iommu_read_reg(mmu, MMU_FAULT_AD); + e.da = fa & PAGE_MASK; + e.pa = virt_to_phys(dummy_addr); + e.valid = 1; + e.prsvd = 1; + e.pgsz = IOVMF_PGSZ_4K & MMU_CAM_PGSZ_MASK; + e.endian = MMU_RAM_ENDIAN_LITTLE; + e.elsz = MMU_RAM_ELSZ_32; + e.mixed = 0; + + load_iotlb_entry(mmu, &e); + + dsp_clk_enable(DSP_CLK_GPT8); + + dsp_gpt_wait_overflow(DSP_CLK_GPT8, 0xfffffffe); + + /* Clear MMU interrupt */ + tmp = iommu_read_reg(mmu, MMU_IRQSTATUS); + iommu_write_reg(mmu, tmp, MMU_IRQSTATUS); + + dump_dsp_stack(dev_context); + dsp_clk_disable(DSP_CLK_GPT8); + + iopgtable_clear_entry(mmu, fa); + free_page((unsigned long)dummy_addr); +} +#endif + + +static void fault_tasklet(unsigned long data) +{ + struct iommu *mmu = (struct iommu *)data; + struct bridge_dev_context *dev_ctx; + struct deh_mgr *dm; + u32 fa; + dev_get_deh_mgr(dev_get_first(), &dm); + dev_get_bridge_context(dev_get_first(), &dev_ctx); + + if (!dm || !dev_ctx) + return; + + fa = iommu_read_reg(mmu, MMU_FAULT_AD); + +#ifdef CONFIG_TIDSPBRIDGE_BACKTRACE + print_dsp_trace_buffer(dev_ctx); + dump_dl_modules(dev_ctx); + mmu_fault_print_stack(dev_ctx); +#endif + + bridge_deh_notify(dm, DSP_MMUFAULT, fa); +} + +/* + * ======== mmu_fault_isr ======== + * ISR to be triggered by a DSP MMU fault interrupt. + */ +static int mmu_fault_callback(struct iommu *mmu) +{ + if (!mmu) + return -EPERM; + + iommu_write_reg(mmu, 0, MMU_IRQENABLE); + tasklet_schedule(&mmu_tasklet); + return 0; +} + +/** + * dsp_mmu_init() - initialize dsp_mmu module and returns a handle + * + * This function initialize dsp mmu module and returns a struct iommu + * handle to use it for dsp maps. + * + */ +struct iommu *dsp_mmu_init() +{ + struct iommu *mmu; + + mmu = iommu_get("iva2"); + + if (!IS_ERR(mmu)) { + tasklet_init(&mmu_tasklet, fault_tasklet, (unsigned long)mmu); + mmu->isr = mmu_fault_callback; + } + + return mmu; +} + +/** + * dsp_mmu_exit() - destroy dsp mmu module + * @mmu: Pointer to iommu handle. + * + * This function destroys dsp mmu module. + * + */ +void dsp_mmu_exit(struct iommu *mmu) +{ + if (mmu) + iommu_put(mmu); + tasklet_kill(&mmu_tasklet); +} + +/** + * user_va2_pa() - get physical address from userspace address. + * @mm: mm_struct Pointer of the process. + * @address: Virtual user space address. + * + */ +static u32 user_va2_pa(struct mm_struct *mm, u32 address) +{ + pgd_t *pgd; + pmd_t *pmd; + pte_t *ptep, pte; + + pgd = pgd_offset(mm, address); + if (!(pgd_none(*pgd) || pgd_bad(*pgd))) { + pmd = pmd_offset(pgd, address); + if (!(pmd_none(*pmd) || pmd_bad(*pmd))) { + ptep = pte_offset_map(pmd, address); + if (ptep) { + pte = *ptep; + if (pte_present(pte)) + return pte & PAGE_MASK; + } + } + } + + return 0; +} + +/** + * get_io_pages() - pin and get pages of io user's buffer. + * @mm: mm_struct Pointer of the process. + * @uva: Virtual user space address. + * @pages Pages to be pined. + * @usr_pgs struct page array pointer where the user pages will be stored + * + */ +static int get_io_pages(struct mm_struct *mm, u32 uva, unsigned pages, + struct page **usr_pgs) +{ + u32 pa; + int i; + struct page *pg; + + for (i = 0; i < pages; i++) { + pa = user_va2_pa(mm, uva); + + if (!pfn_valid(__phys_to_pfn(pa))) + break; + + pg = phys_to_page(pa); + usr_pgs[i] = pg; + get_page(pg); + } + return i; +} + +/** + * user_to_dsp_map() - maps user to dsp virtual address + * @mmu: Pointer to iommu handle. + * @uva: Virtual user space address. + * @da DSP address + * @size Buffer size to map. + * @usr_pgs struct page array pointer where the user pages will be stored + * + * This function maps a user space buffer into DSP virtual address. + * + */ +u32 user_to_dsp_map(struct iommu *mmu, u32 uva, u32 da, u32 size, + struct page **usr_pgs) +{ + int res, w; + unsigned pages; + int i; + struct vm_area_struct *vma; + struct mm_struct *mm = current->mm; + struct sg_table *sgt; + struct scatterlist *sg; + + if (!size || !usr_pgs) + return -EINVAL; + + pages = size / PG_SIZE4K; + + down_read(&mm->mmap_sem); + vma = find_vma(mm, uva); + while (vma && (uva + size > vma->vm_end)) + vma = find_vma(mm, vma->vm_end + 1); + + if (!vma) { + pr_err("%s: Failed to get VMA region for 0x%x (%d)\n", + __func__, uva, size); + up_read(&mm->mmap_sem); + return -EINVAL; + } + if (vma->vm_flags & (VM_WRITE | VM_MAYWRITE)) + w = 1; + + if (vma->vm_flags & VM_IO) + i = get_io_pages(mm, uva, pages, usr_pgs); + else + i = get_user_pages(current, mm, uva, pages, w, 1, + usr_pgs, NULL); + up_read(&mm->mmap_sem); + + if (i < 0) + return i; + + if (i < pages) { + res = -EFAULT; + goto err_pages; + } + + sgt = kzalloc(sizeof(*sgt), GFP_KERNEL); + if (!sgt) { + res = -ENOMEM; + goto err_pages; + } + + res = sg_alloc_table(sgt, pages, GFP_KERNEL); + + if (res < 0) + goto err_sg; + + for_each_sg(sgt->sgl, sg, sgt->nents, i) + sg_set_page(sg, usr_pgs[i], PAGE_SIZE, 0); + + da = iommu_vmap(mmu, da, sgt, IOVMF_ENDIAN_LITTLE | IOVMF_ELSZ_32); + + if (!IS_ERR_VALUE(da)) + return da; + res = (int)da; + + sg_free_table(sgt); +err_sg: + kfree(sgt); + i = pages; +err_pages: + while (i--) + put_page(usr_pgs[i]); + return res; +} + +/** + * user_to_dsp_unmap() - unmaps DSP virtual buffer. + * @mmu: Pointer to iommu handle. + * @da DSP address + * + * This function unmaps a user space buffer into DSP virtual address. + * + */ +int user_to_dsp_unmap(struct iommu *mmu, u32 da) +{ + unsigned i; + struct sg_table *sgt; + struct scatterlist *sg; + + sgt = iommu_vunmap(mmu, da); + if (!sgt) + return -EFAULT; + + for_each_sg(sgt->sgl, sg, sgt->nents, i) + put_page(sg_page(sg)); + sg_free_table(sgt); + kfree(sgt); + + return 0; +} |
