powerpc/mm: dump block address translation on book3s/32

This patch adds a debugfs file to dump block address translation:

~# cat /sys/kernel/debug/powerpc/block_address_translation
---[ Instruction Block Address Translations ]---
0:         -
1:         -
2: 0xc0000000-0xcfffffff 0x00000000 Kernel EXEC coherent
3: 0xd0000000-0xdfffffff 0x10000000 Kernel EXEC coherent
4:         -
5:         -
6:         -
7:         -

---[ Data Block Address Translations ]---
0:         -
1:         -
2: 0xc0000000-0xcfffffff 0x00000000 Kernel RW coherent
3: 0xd0000000-0xdfffffff 0x10000000 Kernel RW coherent
4:         -
5:         -
6:         -
7:         -

Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>

diff --git a/arch/powerpc/include/asm/book3s/32/mmu-hash.h b/arch/powerpc/include/asm/book3s/32/mmu-hash.h
index 2bb500d..7cf4ae8 100644 (file)
--- a/arch/powerpc/include/asm/book3s/32/mmu-hash.h
+++ b/arch/powerpc/include/asm/book3s/32/mmu-hash.h
@@ -37,8 +37,12 @@
 #define BAT_PHYS_ADDR(x) ((u32)((x & 0x00000000fffe0000ULL) | \
                                ((x & 0x0000000e00000000ULL) >> 24) | \
                                ((x & 0x0000000100000000ULL) >> 30)))
+#define PHYS_BAT_ADDR(x) (((u64)(x) & 0x00000000fffe0000ULL) | \
+                         (((u64)(x) << 24) & 0x0000000e00000000ULL) | \
+                         (((u64)(x) << 30) & 0x0000000100000000ULL))
 #else
 #define BAT_PHYS_ADDR(x) (x)
+#define PHYS_BAT_ADDR(x) ((x) & 0xfffe0000)
 #endif
 
 struct ppc_bat {

diff --git a/arch/powerpc/mm/Makefile b/arch/powerpc/mm/Makefile
index e6c77b7..f965fc3 100644 (file)
--- a/arch/powerpc/mm/Makefile
+++ b/arch/powerpc/mm/Makefile
@@ -50,7 +50,7 @@ ifdef CONFIG_PPC_PTDUMP
 obj-$(CONFIG_4xx)              += dump_linuxpagetables-generic.o
 obj-$(CONFIG_PPC_8xx)          += dump_linuxpagetables-8xx.o
 obj-$(CONFIG_PPC_BOOK3E_MMU)   += dump_linuxpagetables-generic.o
-obj-$(CONFIG_PPC_BOOK3S_32)    += dump_linuxpagetables-generic.o dump_sr.o
+obj-$(CONFIG_PPC_BOOK3S_32)    += dump_linuxpagetables-generic.o dump_bats.o dump_sr.o
 obj-$(CONFIG_PPC_BOOK3S_64)    += dump_linuxpagetables-book3s64.o
 endif
 obj-$(CONFIG_PPC_HTDUMP)       += dump_hashpagetable.o

diff --git a/arch/powerpc/mm/dump_bats.c b/arch/powerpc/mm/dump_bats.c
new file mode 100644 (file)
index 0000000..a0d23e9
--- /dev/null
+++ b/arch/powerpc/mm/dump_bats.c
@@ -0,0 +1,173 @@
+// SPDX-License-Identifier: GPL-2.0+
+/*
+ * Copyright 2018, Christophe Leroy CS S.I.
+ * <christophe.leroy@c-s.fr>
+ *
+ * This dumps the content of BATS
+ */
+
+#include <asm/debugfs.h>
+#include <asm/pgtable.h>
+#include <asm/cpu_has_feature.h>
+
+static char *pp_601(int k, int pp)
+{
+       if (pp == 0)
+               return k ? "NA" : "RWX";
+       if (pp == 1)
+               return k ? "ROX" : "RWX";
+       if (pp == 2)
+               return k ? "RWX" : "RWX";
+       return k ? "ROX" : "ROX";
+}
+
+static void bat_show_601(struct seq_file *m, int idx, u32 lower, u32 upper)
+{
+       u32 blpi = upper & 0xfffe0000;
+       u32 k = (upper >> 2) & 3;
+       u32 pp = upper & 3;
+       phys_addr_t pbn = PHYS_BAT_ADDR(lower);
+       u32 bsm = lower & 0x3ff;
+       u32 size = (bsm + 1) << 17;
+
+       seq_printf(m, "%d: ", idx);
+       if (!(lower & 0x40)) {
+               seq_puts(m, "        -\n");
+               return;
+       }
+
+       seq_printf(m, "0x%08x-0x%08x ", blpi, blpi + size - 1);
+#ifdef CONFIG_PHYS_64BIT
+       seq_printf(m, "0x%016llx ", pbn);
+#else
+       seq_printf(m, "0x%08x ", pbn);
+#endif
+
+       seq_printf(m, "Kernel %s User %s", pp_601(k & 2, pp), pp_601(k & 1, pp));
+
+       if (lower & _PAGE_WRITETHRU)
+               seq_puts(m, "write through ");
+       if (lower & _PAGE_NO_CACHE)
+               seq_puts(m, "no cache ");
+       if (lower & _PAGE_COHERENT)
+               seq_puts(m, "coherent ");
+       seq_puts(m, "\n");
+}
+
+#define BAT_SHOW_601(_m, _n, _l, _u) bat_show_601(_m, _n, mfspr(_l), mfspr(_u))
+
+static int bats_show_601(struct seq_file *m, void *v)
+{
+       seq_puts(m, "---[ Block Address Translation ]---\n");
+
+       BAT_SHOW_601(m, 0, SPRN_IBAT0L, SPRN_IBAT0U);
+       BAT_SHOW_601(m, 1, SPRN_IBAT1L, SPRN_IBAT1U);
+       BAT_SHOW_601(m, 2, SPRN_IBAT2L, SPRN_IBAT2U);
+       BAT_SHOW_601(m, 3, SPRN_IBAT3L, SPRN_IBAT3U);
+
+       return 0;
+}
+
+static void bat_show_603(struct seq_file *m, int idx, u32 lower, u32 upper, bool is_d)
+{
+       u32 bepi = upper & 0xfffe0000;
+       u32 bl = (upper >> 2) & 0x7ff;
+       u32 k = upper & 3;
+       phys_addr_t brpn = PHYS_BAT_ADDR(lower);
+       u32 size = (bl + 1) << 17;
+
+       seq_printf(m, "%d: ", idx);
+       if (k == 0) {
+               seq_puts(m, "        -\n");
+               return;
+       }
+
+       seq_printf(m, "0x%08x-0x%08x ", bepi, bepi + size - 1);
+#ifdef CONFIG_PHYS_64BIT
+       seq_printf(m, "0x%016llx ", brpn);
+#else
+       seq_printf(m, "0x%08x ", brpn);
+#endif
+
+       if (k == 1)
+               seq_puts(m, "User ");
+       else if (k == 2)
+               seq_puts(m, "Kernel ");
+       else
+               seq_puts(m, "Kernel/User ");
+
+       if (lower & BPP_RX)
+               seq_puts(m, is_d ? "RO " : "EXEC ");
+       else if (lower & BPP_RW)
+               seq_puts(m, is_d ? "RW " : "EXEC ");
+       else
+               seq_puts(m, is_d ? "NA " : "NX   ");
+
+       if (lower & _PAGE_WRITETHRU)
+               seq_puts(m, "write through ");
+       if (lower & _PAGE_NO_CACHE)
+               seq_puts(m, "no cache ");
+       if (lower & _PAGE_COHERENT)
+               seq_puts(m, "coherent ");
+       if (lower & _PAGE_GUARDED)
+               seq_puts(m, "guarded ");
+       seq_puts(m, "\n");
+}
+
+#define BAT_SHOW_603(_m, _n, _l, _u, _d) bat_show_603(_m, _n, mfspr(_l), mfspr(_u), _d)
+
+static int bats_show_603(struct seq_file *m, void *v)
+{
+       seq_puts(m, "---[ Instruction Block Address Translation ]---\n");
+
+       BAT_SHOW_603(m, 0, SPRN_IBAT0L, SPRN_IBAT0U, false);
+       BAT_SHOW_603(m, 1, SPRN_IBAT1L, SPRN_IBAT1U, false);
+       BAT_SHOW_603(m, 2, SPRN_IBAT2L, SPRN_IBAT2U, false);
+       BAT_SHOW_603(m, 3, SPRN_IBAT3L, SPRN_IBAT3U, false);
+       if (mmu_has_feature(MMU_FTR_USE_HIGH_BATS)) {
+               BAT_SHOW_603(m, 4, SPRN_IBAT4L, SPRN_IBAT4U, false);
+               BAT_SHOW_603(m, 5, SPRN_IBAT5L, SPRN_IBAT5U, false);
+               BAT_SHOW_603(m, 6, SPRN_IBAT6L, SPRN_IBAT6U, false);
+               BAT_SHOW_603(m, 7, SPRN_IBAT7L, SPRN_IBAT7U, false);
+       }
+
+       seq_puts(m, "\n---[ Data Block Address Translation ]---\n");
+
+       BAT_SHOW_603(m, 0, SPRN_DBAT0L, SPRN_DBAT0U, true);
+       BAT_SHOW_603(m, 1, SPRN_DBAT1L, SPRN_DBAT1U, true);
+       BAT_SHOW_603(m, 2, SPRN_DBAT2L, SPRN_DBAT2U, true);
+       BAT_SHOW_603(m, 3, SPRN_DBAT3L, SPRN_DBAT3U, true);
+       if (mmu_has_feature(MMU_FTR_USE_HIGH_BATS)) {
+               BAT_SHOW_603(m, 4, SPRN_DBAT4L, SPRN_DBAT4U, true);
+               BAT_SHOW_603(m, 5, SPRN_DBAT5L, SPRN_DBAT5U, true);
+               BAT_SHOW_603(m, 6, SPRN_DBAT6L, SPRN_DBAT6U, true);
+               BAT_SHOW_603(m, 7, SPRN_DBAT7L, SPRN_DBAT7U, true);
+       }
+
+       return 0;
+}
+
+static int bats_open(struct inode *inode, struct file *file)
+{
+       if (cpu_has_feature(CPU_FTR_601))
+               return single_open(file, bats_show_601, NULL);
+
+       return single_open(file, bats_show_603, NULL);
+}
+
+static const struct file_operations bats_fops = {
+       .open           = bats_open,
+       .read           = seq_read,
+       .llseek         = seq_lseek,
+       .release        = single_release,
+};
+
+static int __init bats_init(void)
+{
+       struct dentry *debugfs_file;
+
+       debugfs_file = debugfs_create_file("block_address_translation", 0400,
+                                          powerpc_debugfs_root, NULL, &bats_fops);
+       return debugfs_file ? 0 : -ENOMEM;
+}
+device_initcall(bats_init);