This patch dumps all active mapping entries from pagetable to a debugfs directory named "mappings". Part of this patch for listing all swgroup names in a group_soc is provided by Dmitry Osipenko <digetx@xxxxxxxxx> Attaching an example: [SWGROUP: xusb_host] [as: (id: 5), (attr: R|W|-), (pd_dma: 0x0000000080005000)] { [index: 1023] 0xf0080007 (count: 52) { PTE RANGE | ATTR | PHYS | IOVA | SIZE [#913 , #913 ] | 0x7 | 0x0000000101fbe000 | 0xfff91000 | 0x1000 [#914 , #914 ] | 0x7 | 0x0000000101fbd000 | 0xfff92000 | 0x1000 [#915 , #915 ] | 0x7 | 0x0000000101fbc000 | 0xfff93000 | 0x1000 [#916 , #916 ] | 0x7 | 0x0000000101fbb000 | 0xfff94000 | 0x1000 [#921 , #921 ] | 0x7 | 0x00000000fcc02000 | 0xfff99000 | 0x1000 [#922 , #922 ] | 0x7 | 0x0000000101fb7000 | 0xfff9a000 | 0x1000 [#923 , #923 ] | 0x7 | 0x0000000101fb5000 | 0xfff9b000 | 0x1000 [#948 , #948 ] | 0x7 | 0x0000000101fb2000 | 0xfffb4000 | 0x1000 [#949 , #949 ] | 0x7 | 0x0000000101fb1000 | 0xfffb5000 | 0x1000 [#950 , #950 ] | 0x7 | 0x0000000101faf000 | 0xfffb6000 | 0x1000 [#951 , #951 ] | 0x7 | 0x0000000101fae000 | 0xfffb7000 | 0x1000 [#952 , #952 ] | 0x7 | 0x000000010263d000 | 0xfffb8000 | 0x1000 [#953 , #953 ] | 0x7 | 0x000000010263c000 | 0xfffb9000 | 0x1000 [#954 , #954 ] | 0x7 | 0x000000010263b000 | 0xfffba000 | 0x1000 [#955 , #955 ] | 0x7 | 0x000000010263a000 | 0xfffbb000 | 0x1000 [#956 , #956 ] | 0x7 | 0x0000000102639000 | 0xfffbc000 | 0x1000 [#957 , #957 ] | 0x7 | 0x0000000102638000 | 0xfffbd000 | 0x1000 [#958 , #958 ] | 0x7 | 0x0000000102637000 | 0xfffbe000 | 0x1000 [#959 , #959 ] | 0x7 | 0x0000000102636000 | 0xfffbf000 | 0x1000 [#960 , #992 ] | 0x7 | 0x0000000102613000 | 0xfffc0000 | 0x21000 } } Total PDEs: 1, total PTEs: 52 Note that the example above was output after I locally enabled IOMMU_DOMAIN_DMA, which is not merged to mainline yet due to a known framebuffer issue. Signed-off-by: Nicolin Chen <nicolinc@xxxxxxxxxx> --- drivers/iommu/tegra-smmu.c | 185 +++++++++++++++++++++++++++++++++++++ 1 file changed, 185 insertions(+) diff --git a/drivers/iommu/tegra-smmu.c b/drivers/iommu/tegra-smmu.c index 454504aa6602..cbd1a52f2a9f 100644 --- a/drivers/iommu/tegra-smmu.c +++ b/drivers/iommu/tegra-smmu.c @@ -47,6 +47,7 @@ struct tegra_smmu { struct list_head list; struct dentry *debugfs; + struct dentry *debugfs_mappings; struct iommu_device iommu; /* IOMMU Core code handle */ }; @@ -154,6 +155,9 @@ static inline u32 smmu_readl(struct tegra_smmu *smmu, unsigned long offset) #define SMMU_PDE_ATTR (SMMU_PDE_READABLE | SMMU_PDE_WRITABLE | \ SMMU_PDE_NONSECURE) +#define SMMU_PTE_ATTR (SMMU_PTE_READABLE | SMMU_PTE_WRITABLE | \ + SMMU_PTE_NONSECURE) +#define SMMU_PTE_ATTR_SHIFT 29 static unsigned int iova_pd_index(unsigned long iova) { @@ -165,6 +169,12 @@ static unsigned int iova_pt_index(unsigned long iova) return (iova >> SMMU_PTE_SHIFT) & (SMMU_NUM_PTE - 1); } +static unsigned long pd_pt_index_iova(unsigned int pd_index, unsigned int pt_index) +{ + return (pd_index & (SMMU_NUM_PDE - 1)) << SMMU_PDE_SHIFT | + (pt_index & (SMMU_NUM_PTE - 1)) << SMMU_PTE_SHIFT; +} + static bool smmu_dma_addr_valid(struct tegra_smmu *smmu, dma_addr_t addr) { addr >>= 12; @@ -498,6 +508,156 @@ static void tegra_smmu_as_unprepare(struct tegra_smmu *smmu, mutex_unlock(&smmu->lock); } +static int tegra_smmu_debugfs_mappings_show(struct seq_file *s, void *data) +{ + struct tegra_smmu_group *group = s->private; + const struct tegra_smmu_group_soc *soc; + const struct tegra_smmu_swgroup *swgrp; + struct tegra_smmu_as *as; + struct tegra_smmu *smmu; + unsigned int pd_index; + unsigned int pt_index; + unsigned long flags; + u64 pte_count = 0; + u32 pde_count = 0; + u32 *pd, val; + + if (!group || !group->as || !group->swgrp) + return 0; + + swgrp = group->swgrp; + smmu = group->smmu; + soc = group->soc; + as = group->as; + + mutex_lock(&smmu->lock); + + val = smmu_readl(smmu, swgrp->reg); + if (!(val & SMMU_ASID_ENABLE)) + goto unlock; + + pd = page_address(as->pd); + if (!pd) + goto unlock; + + seq_puts(s, "[SWGROUP: "); + /* List all the swgroup names in the same group_soc */ + if (soc) { + bool first_swgroup = true; + unsigned int i; + + for (i = 0; i < soc->num_swgroups; i++) { + swgrp = tegra_smmu_find_swgrp(smmu, soc->swgroups[i]); + if (WARN_ON(!swgrp)) + goto unlock; + + val = smmu_readl(smmu, swgrp->reg); + if (!(val & SMMU_ASID_ENABLE)) + continue; + + if (WARN_ON((val & SMMU_ASID_MASK) != as->id)) + continue; + + if (first_swgroup) + first_swgroup = false; + else + seq_puts(s, ", "); + + seq_printf(s, "%s", swgrp->name); + } + } else { + WARN_ON((val & SMMU_ASID_MASK) != as->id); + seq_printf(s, "%s", swgrp->name); + } + seq_puts(s, "] "); + + seq_printf(s, "[as: (id: %d), ", as->id); + seq_printf(s, "(attr: %c|%c|%c), ", + as->attr & SMMU_PD_READABLE ? 'R' : '-', + as->attr & SMMU_PD_WRITABLE ? 'W' : '-', + as->attr & SMMU_PD_NONSECURE ? '-' : 'S'); + seq_printf(s, "(pd_dma: %pad)]\n", &as->pd_dma); + seq_puts(s, "{\n"); + + spin_lock_irqsave(&as->lock, flags); + + for (pd_index = 0; pd_index < SMMU_NUM_PDE; pd_index++) { + struct page *pt_page; + unsigned int i; + u32 *addr; + + /* An empty PDE should not have a pte use count */ + WARN_ON_ONCE(!pd[pd_index] ^ !as->count[pd_index]); + + /* Skip this empty PDE */ + if (!pd[pd_index]) + continue; + + pde_count++; + pte_count += as->count[pd_index]; + seq_printf(s, "\t[index: %u] 0x%x (count: %d)\n", + pd_index, pd[pd_index], as->count[pd_index]); + pt_page = as->pts[pd_index]; + addr = page_address(pt_page); + + seq_puts(s, "\t{\n"); + seq_printf(s, "\t\t%-14s | %-4s | %-10s%s | %-10s | %-11s\n", + "PTE RANGE", "ATTR", + "PHYS", sizeof(phys_addr_t) > 4 ? " " : "", + "IOVA", "SIZE"); + for (pt_index = 0; pt_index < SMMU_NUM_PTE; pt_index += i) { + size_t size = SMMU_SIZE_PT; + dma_addr_t iova; + phys_addr_t pa; + + i = 1; + + if (!addr[pt_index]) + continue; + + iova = pd_pt_index_iova(pd_index, pt_index); + pa = SMMU_PFN_PHYS(addr[pt_index] & ~SMMU_PTE_ATTR); + + /* Check contiguous mappings and increase size */ + while (pt_index + i < SMMU_NUM_PTE) { + dma_addr_t next_iova; + phys_addr_t next_pa; + + if (!addr[pt_index + i]) + break; + + next_iova = pd_pt_index_iova(pd_index, pt_index + i); + next_pa = SMMU_PFN_PHYS(addr[pt_index + i] & ~SMMU_PTE_ATTR); + + /* Break at the end of a linear mapping */ + if ((next_iova - iova != SMMU_SIZE_PT * i) || + (next_pa - pa != SMMU_SIZE_PT * i)) + break; + + i++; + } + + seq_printf(s, "\t\t[#%-4u, #%-4u] | 0x%-2x | %pa | 0x%-8x | 0x%-9zx\n", + pt_index, pt_index + i - 1, + addr[pt_index] >> SMMU_PTE_ATTR_SHIFT, + &pa, (u32)iova, size * i); + } + seq_puts(s, "\t}\n"); + } + + spin_unlock_irqrestore(&as->lock, flags); + + seq_puts(s, "}\n"); + seq_printf(s, "Total PDEs: %u, total PTEs: %llu\n ", pde_count, pte_count); + +unlock: + mutex_unlock(&smmu->lock); + + return 0; +} + +DEFINE_SHOW_ATTRIBUTE(tegra_smmu_debugfs_mappings); + static void tegra_smmu_attach_as(struct tegra_smmu *smmu, struct tegra_smmu_as *as, unsigned int swgroup) @@ -522,6 +682,20 @@ static void tegra_smmu_attach_as(struct tegra_smmu *smmu, dev_warn(smmu->dev, "overwriting group->as for swgroup: %s\n", swgrp->name); group->as = as; + + if (smmu->debugfs_mappings) { + const char *name; + + if (group->soc) + name = group->soc->name; + else + name = group->swgrp->name; + + debugfs_create_file(name, 0444, + smmu->debugfs_mappings, group, + &tegra_smmu_debugfs_mappings_fops); + } + break; } @@ -545,6 +719,15 @@ static void tegra_smmu_detach_as(struct tegra_smmu *smmu, if (group->swgrp != swgrp) continue; group->as = NULL; + + if (smmu->debugfs_mappings) { + struct dentry *d; + + d = debugfs_lookup(group->swgrp->name, + smmu->debugfs_mappings); + debugfs_remove(d); + } + break; } @@ -1137,6 +1320,8 @@ static void tegra_smmu_debugfs_init(struct tegra_smmu *smmu) &tegra_smmu_swgroups_fops); debugfs_create_file("clients", S_IRUGO, smmu->debugfs, smmu, &tegra_smmu_clients_fops); + + smmu->debugfs_mappings = debugfs_create_dir("mappings", smmu->debugfs); } static void tegra_smmu_debugfs_exit(struct tegra_smmu *smmu) -- 2.17.1