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-rw-r--r--Documentation/xtensa/mmu.txt18
-rw-r--r--arch/xtensa/include/asm/initialize_mmu.h9
-rw-r--r--arch/xtensa/include/asm/io.h10
-rw-r--r--arch/xtensa/include/asm/vectors.h8
-rw-r--r--arch/xtensa/kernel/setup.c37
-rw-r--r--arch/xtensa/mm/mmu.c16
6 files changed, 93 insertions, 5 deletions
diff --git a/Documentation/xtensa/mmu.txt b/Documentation/xtensa/mmu.txt
index 2b1af7606d57..0312fe66475c 100644
--- a/Documentation/xtensa/mmu.txt
+++ b/Documentation/xtensa/mmu.txt
@@ -44,3 +44,21 @@ After step 4, we jump to intended (linked) address of this code.
40..5F -> 40 40..5F -> pc -> pc 40..5F -> pc
20..3F -> 20 -> 20 20..3F -> 20
00..1F -> 00 -> 00 00..1F -> 00
+
+The default location of IO peripherals is above 0xf0000000. This may change
+using a "ranges" property in a device tree simple-bus node. See ePAPR 1.1, ยง6.5
+for details on the syntax and semantic of simple-bus nodes. The following
+limitations apply:
+
+1. Only top level simple-bus nodes are considered
+
+2. Only one (first) simple-bus node is considered
+
+3. Empty "ranges" properties are not supported
+
+4. Only the first triplet in the "ranges" property is considered
+
+5. The parent-bus-address value is rounded down to the nearest 256MB boundary
+
+6. The IO area covers the entire 256MB segment of parent-bus-address; the
+ "ranges" triplet length field is ignored
diff --git a/arch/xtensa/include/asm/initialize_mmu.h b/arch/xtensa/include/asm/initialize_mmu.h
index a2078a2e5476..600781edc8a3 100644
--- a/arch/xtensa/include/asm/initialize_mmu.h
+++ b/arch/xtensa/include/asm/initialize_mmu.h
@@ -26,6 +26,9 @@
#include <asm/pgtable.h>
#include <asm/vectors.h>
+#define CA_BYPASS (_PAGE_CA_BYPASS | _PAGE_HW_WRITE | _PAGE_HW_EXEC)
+#define CA_WRITEBACK (_PAGE_CA_WB | _PAGE_HW_WRITE | _PAGE_HW_EXEC)
+
#ifdef __ASSEMBLY__
#define XTENSA_HWVERSION_RC_2009_0 230000
@@ -80,8 +83,6 @@
/* Step 2: map 0x40000000..0x47FFFFFF to paddr containing this code
* and jump to the new mapping.
*/
-#define CA_BYPASS (_PAGE_CA_BYPASS | _PAGE_HW_WRITE | _PAGE_HW_EXEC)
-#define CA_WRITEBACK (_PAGE_CA_WB | _PAGE_HW_WRITE | _PAGE_HW_EXEC)
srli a3, a0, 27
slli a3, a3, 27
@@ -124,12 +125,12 @@
witlb a4, a5
movi a5, XCHAL_KIO_CACHED_VADDR + 6
- movi a4, XCHAL_KIO_PADDR + CA_WRITEBACK
+ movi a4, XCHAL_KIO_DEFAULT_PADDR + CA_WRITEBACK
wdtlb a4, a5
witlb a4, a5
movi a5, XCHAL_KIO_BYPASS_VADDR + 6
- movi a4, XCHAL_KIO_PADDR + CA_BYPASS
+ movi a4, XCHAL_KIO_DEFAULT_PADDR + CA_BYPASS
wdtlb a4, a5
witlb a4, a5
diff --git a/arch/xtensa/include/asm/io.h b/arch/xtensa/include/asm/io.h
index 1482a3636381..2a042d430c25 100644
--- a/arch/xtensa/include/asm/io.h
+++ b/arch/xtensa/include/asm/io.h
@@ -24,6 +24,16 @@
#define IO_SPACE_LIMIT ~0
#ifdef CONFIG_MMU
+
+#if XCHAL_HAVE_PTP_MMU && XCHAL_HAVE_SPANNING_WAY && CONFIG_OF
+extern unsigned long xtensa_kio_paddr;
+
+static inline unsigned long xtensa_get_kio_paddr(void)
+{
+ return xtensa_kio_paddr;
+}
+#endif
+
/*
* Return the virtual address for the specified bus memory.
* Note that we currently don't support any address outside the KIO segment.
diff --git a/arch/xtensa/include/asm/vectors.h b/arch/xtensa/include/asm/vectors.h
index 221a60d804d5..5791b45d5a5d 100644
--- a/arch/xtensa/include/asm/vectors.h
+++ b/arch/xtensa/include/asm/vectors.h
@@ -22,9 +22,15 @@
#define XCHAL_KIO_CACHED_VADDR 0xe0000000
#define XCHAL_KIO_BYPASS_VADDR 0xf0000000
-#define XCHAL_KIO_PADDR 0xf0000000
+#define XCHAL_KIO_DEFAULT_PADDR 0xf0000000
#define XCHAL_KIO_SIZE 0x10000000
+#if XCHAL_HAVE_PTP_MMU && XCHAL_HAVE_SPANNING_WAY && CONFIG_OF
+#define XCHAL_KIO_PADDR xtensa_get_kio_paddr()
+#else
+#define XCHAL_KIO_PADDR XCHAL_KIO_DEFAULT_PADDR
+#endif
+
#if defined(CONFIG_MMU)
/* Will Become VECBASE */
diff --git a/arch/xtensa/kernel/setup.c b/arch/xtensa/kernel/setup.c
index f38badeb7747..7d12af1317f1 100644
--- a/arch/xtensa/kernel/setup.c
+++ b/arch/xtensa/kernel/setup.c
@@ -212,6 +212,42 @@ static int __init parse_bootparam(const bp_tag_t* tag)
#ifdef CONFIG_OF
bool __initdata dt_memory_scan = false;
+#if XCHAL_HAVE_PTP_MMU && XCHAL_HAVE_SPANNING_WAY
+unsigned long xtensa_kio_paddr = XCHAL_KIO_DEFAULT_PADDR;
+EXPORT_SYMBOL(xtensa_kio_paddr);
+
+static int __init xtensa_dt_io_area(unsigned long node, const char *uname,
+ int depth, void *data)
+{
+ const __be32 *ranges;
+ unsigned long len;
+
+ if (depth > 1)
+ return 0;
+
+ if (!of_flat_dt_is_compatible(node, "simple-bus"))
+ return 0;
+
+ ranges = of_get_flat_dt_prop(node, "ranges", &len);
+ if (!ranges)
+ return 1;
+ if (len == 0)
+ return 1;
+
+ xtensa_kio_paddr = of_read_ulong(ranges+1, 1);
+ /* round down to nearest 256MB boundary */
+ xtensa_kio_paddr &= 0xf0000000;
+
+ return 1;
+}
+#else
+static int __init xtensa_dt_io_area(unsigned long node, const char *uname,
+ int depth, void *data)
+{
+ return 1;
+}
+#endif
+
void __init early_init_dt_add_memory_arch(u64 base, u64 size)
{
if (!dt_memory_scan)
@@ -232,6 +268,7 @@ void __init early_init_devtree(void *params)
dt_memory_scan = true;
early_init_dt_scan(params);
+ of_scan_flat_dt(xtensa_dt_io_area, NULL);
if (!command_line[0])
strlcpy(command_line, boot_command_line, COMMAND_LINE_SIZE);
diff --git a/arch/xtensa/mm/mmu.c b/arch/xtensa/mm/mmu.c
index 5bb8e3c61d85..36ec171698b8 100644
--- a/arch/xtensa/mm/mmu.c
+++ b/arch/xtensa/mm/mmu.c
@@ -13,6 +13,8 @@
#include <asm/tlbflush.h>
#include <asm/mmu_context.h>
#include <asm/page.h>
+#include <asm/initialize_mmu.h>
+#include <asm/io.h>
void __init paging_init(void)
{
@@ -37,6 +39,20 @@ void init_mmu(void)
set_itlbcfg_register(0);
set_dtlbcfg_register(0);
#endif
+#if XCHAL_HAVE_PTP_MMU && XCHAL_HAVE_SPANNING_WAY && CONFIG_OF
+ /*
+ * Update the IO area mapping in case xtensa_kio_paddr has changed
+ */
+ write_dtlb_entry(__pte(xtensa_kio_paddr + CA_WRITEBACK),
+ XCHAL_KIO_CACHED_VADDR + 6);
+ write_itlb_entry(__pte(xtensa_kio_paddr + CA_WRITEBACK),
+ XCHAL_KIO_CACHED_VADDR + 6);
+ write_dtlb_entry(__pte(xtensa_kio_paddr + CA_BYPASS),
+ XCHAL_KIO_BYPASS_VADDR + 6);
+ write_itlb_entry(__pte(xtensa_kio_paddr + CA_BYPASS),
+ XCHAL_KIO_BYPASS_VADDR + 6);
+#endif
+
local_flush_tlb_all();
/* Set rasid register to a known value. */