7 files changed, 164 insertions, 25 deletions

diff --git a/arch/xtensa/Kconfig b/arch/xtensa/Kconfig
index 1816abc5c8d5..8ceb5b2ffbb1 100644
--- a/arch/xtensa/Kconfig
+++ b/arch/xtensa/Kconfig
@@ -178,6 +178,17 @@ config CMDLINE
           time by entering them here. As a minimum, you should specify the
           memory size and the root device (e.g., mem=64M root=/dev/nfs).
 
+config USE_OF
+        bool "Flattened Device Tree support"
+        select OF
+        select OF_EARLY_FLATTREE
+        help
+          Include support for flattened device tree machine descriptions.
+
+config BUILTIN_DTB
+        string "DTB to build into the kernel image"
+        depends on OF
+
 source "mm/Kconfig"
 
 source "drivers/pcmcia/Kconfig"
diff --git a/arch/xtensa/Makefile b/arch/xtensa/Makefile
index ab63c9beb930..227f658fc2b9 100644
--- a/arch/xtensa/Makefile
+++ b/arch/xtensa/Makefile
@@ -79,6 +79,10 @@ core-y		+= $(buildvar) $(buildplf)
 
 libs-y          += arch/xtensa/lib/ $(LIBGCC)
 
+ifneq ($(CONFIG_BUILTIN_DTB),"")
+core-y += arch/xtensa/boot/
+endif
+
 boot            := arch/xtensa/boot
 
 all: zImage
@@ -88,6 +92,9 @@ bzImage : zImage
 zImage: vmlinux
         $(Q)$(MAKE) $(build)=$(boot) $@
 
+%.dtb:
+        $(Q)$(MAKE) $(build)=$(boot) $(boot)/$@
+
 define archhelp
   @echo '* zImage      - Compressed kernel image (arch/xtensa/boot/images/zImage.*)'
 endef
diff --git a/arch/xtensa/boot/Makefile b/arch/xtensa/boot/Makefile
index ff974fc2935b..cb5ff4dbdf88 100644
--- a/arch/xtensa/boot/Makefile
+++ b/arch/xtensa/boot/Makefile
@@ -25,6 +25,17 @@ bootdir-$(CONFIG_XTENSA_PLATFORM_ISS)	 += boot-elf
 bootdir-$(CONFIG_XTENSA_PLATFORM_XT2000) += boot-redboot boot-elf boot-uboot
 
 
+BUILTIN_DTB := $(patsubst "%",%,$(CONFIG_BUILTIN_DTB)).dtb.o
+ifneq ($(CONFIG_BUILTIN_DTB),"")
+obj-y += $(BUILTIN_DTB)
+endif
+
+# Rule to build device tree blobs
+$(obj)/%.dtb: $(src)/dts/%.dts FORCE
+        $(call if_changed_dep,dtc)
+
+clean-files := *.dtb.S
+
 zImage Image: $(bootdir-y)
 
 $(bootdir-y): $(addprefix $(obj)/,$(subdir-y)) \
diff --git a/arch/xtensa/include/asm/bootparam.h b/arch/xtensa/include/asm/bootparam.h
index 9983f2c1b7ee..057077e96c98 100644
--- a/arch/xtensa/include/asm/bootparam.h
+++ b/arch/xtensa/include/asm/bootparam.h
@@ -22,6 +22,7 @@
 #define BP_TAG_MEMORY           0x1003  /* memory addr and size (bp_meminfo) */
 #define BP_TAG_SERIAL_BAUSRATE  0x1004  /* baud rate of current console. */
 #define BP_TAG_SERIAL_PORT      0x1005  /* serial device of current console */
+#define BP_TAG_FDT              0x1006  /* flat device tree addr */
 
 #define BP_TAG_FIRST            0x7B0B  /* first tag with a version number */
 #define BP_TAG_LAST             0x7E0B  /* last tag */
diff --git a/arch/xtensa/include/asm/prom.h b/arch/xtensa/include/asm/prom.h
new file mode 100644
index 000000000000..f3d7cd2c0de7
--- /dev/null
+++ b/arch/xtensa/include/asm/prom.h
@@ -0,0 +1,6 @@
+#ifndef _XTENSA_ASM_PROM_H
+#define _XTENSA_ASM_PROM_H
+
+#define HAVE_ARCH_DEVTREE_FIXUPS
+
+#endif /* _XTENSA_ASM_PROM_H */
diff --git a/arch/xtensa/kernel/irq.c b/arch/xtensa/kernel/irq.c
index e90d78211195..6f4f9749cff7 100644
--- a/arch/xtensa/kernel/irq.c
+++ b/arch/xtensa/kernel/irq.c
@@ -19,6 +19,7 @@
 #include <linux/irq.h>
 #include <linux/kernel_stat.h>
 #include <linux/irqdomain.h>
+#include <linux/of.h>
 
 #include <asm/uaccess.h>
 #include <asm/platform.h>
@@ -199,8 +200,17 @@ void __init init_IRQ(void)
         cached_irq_mask = 0;
         set_sr(~0, intclear);
 
+#ifdef CONFIG_OF
+        /* The interrupt controller device node is mandatory */
+        intc = of_find_compatible_node(NULL, NULL, "xtensa,pic");
+        BUG_ON(!intc);
+
+        root_domain = irq_domain_add_linear(intc, NR_IRQS,
+                        &xtensa_irq_domain_ops, NULL);
+#else
         root_domain = irq_domain_add_legacy(intc, NR_IRQS, 0, 0,
                         &xtensa_irq_domain_ops, NULL);
+#endif
         irq_set_default_host(root_domain);
 
         variant_init_irq();
diff --git a/arch/xtensa/kernel/setup.c b/arch/xtensa/kernel/setup.c
index 45217617c60d..64d80e4b0bd4 100644
--- a/arch/xtensa/kernel/setup.c
+++ b/arch/xtensa/kernel/setup.c
@@ -22,6 +22,11 @@
 #include <linux/bootmem.h>
 #include <linux/kernel.h>
 
+#ifdef CONFIG_OF
+#include <linux/of_fdt.h>
+#include <linux/of_platform.h>
+#endif
+
 #if defined(CONFIG_VGA_CONSOLE) || defined(CONFIG_DUMMY_CONSOLE)
 # include <linux/console.h>
 #endif
@@ -65,6 +70,11 @@ int initrd_is_mapped = 0;
 extern int initrd_below_start_ok;
 #endif
 
+#ifdef CONFIG_OF
+extern u32 __dtb_start[];
+void *dtb_start = __dtb_start;
+#endif
+
 unsigned char aux_device_present;
 extern unsigned long loops_per_jiffy;
 
@@ -84,6 +94,8 @@ extern void init_mmu(void);
 static inline void init_mmu(void) { }
 #endif
 
+extern int mem_reserve(unsigned long, unsigned long, int);
+extern void bootmem_init(void);
 extern void zones_init(void);
 
 /*
@@ -105,28 +117,33 @@ typedef struct tagtable {
 
 /* parse current tag */
 
-static int __init parse_tag_mem(const bp_tag_t *tag)
+static int __init add_sysmem_bank(unsigned long type, unsigned long start,
+                unsigned long end)
 {
-        meminfo_t *mi = (meminfo_t*)(tag->data);
-
-        if (mi->type != MEMORY_TYPE_CONVENTIONAL)
-                return -1;
-
         if (sysmem.nr_banks >= SYSMEM_BANKS_MAX) {
                 printk(KERN_WARNING
-                       "Ignoring memory bank 0x%08lx size %ldKB\n",
-                       (unsigned long)mi->start,
-                       (unsigned long)mi->end - (unsigned long)mi->start);
+                                "Ignoring memory bank 0x%08lx size %ldKB\n",
+                                start, end - start);
                 return -EINVAL;
         }
-        sysmem.bank[sysmem.nr_banks].type  = mi->type;
-        sysmem.bank[sysmem.nr_banks].start = PAGE_ALIGN(mi->start);
-        sysmem.bank[sysmem.nr_banks].end   = mi->end & PAGE_MASK;
+        sysmem.bank[sysmem.nr_banks].type  = type;
+        sysmem.bank[sysmem.nr_banks].start = PAGE_ALIGN(start);
+        sysmem.bank[sysmem.nr_banks].end   = end & PAGE_MASK;
         sysmem.nr_banks++;
 
         return 0;
 }
 
+static int __init parse_tag_mem(const bp_tag_t *tag)
+{
+        meminfo_t *mi = (meminfo_t *)(tag->data);
+
+        if (mi->type != MEMORY_TYPE_CONVENTIONAL)
+                return -1;
+
+        return add_sysmem_bank(mi->type, mi->start, mi->end);
+}
+
 __tagtable(BP_TAG_MEMORY, parse_tag_mem);
 
 #ifdef CONFIG_BLK_DEV_INITRD
@@ -143,12 +160,31 @@ static int __init parse_tag_initrd(const bp_tag_t* tag)
 
 __tagtable(BP_TAG_INITRD, parse_tag_initrd);
 
+#ifdef CONFIG_OF
+
+static int __init parse_tag_fdt(const bp_tag_t *tag)
+{
+        dtb_start = (void *)(tag->data[0]);
+        return 0;
+}
+
+__tagtable(BP_TAG_FDT, parse_tag_fdt);
+
+void __init early_init_dt_setup_initrd_arch(unsigned long start,
+                unsigned long end)
+{
+        initrd_start = (void *)__va(start);
+        initrd_end = (void *)__va(end);
+        initrd_below_start_ok = 1;
+}
+
+#endif /* CONFIG_OF */
+
 #endif /* CONFIG_BLK_DEV_INITRD */
 
 static int __init parse_tag_cmdline(const bp_tag_t* tag)
 {
-        strncpy(command_line, (char*)(tag->data), COMMAND_LINE_SIZE);
-        command_line[COMMAND_LINE_SIZE - 1] = '\0';
+        strlcpy(command_line, (char *)(tag->data), COMMAND_LINE_SIZE);
         return 0;
 }
 
@@ -186,6 +222,58 @@ static int __init parse_bootparam(const bp_tag_t* tag)
         return 0;
 }
 
+#ifdef CONFIG_OF
+
+void __init early_init_dt_add_memory_arch(u64 base, u64 size)
+{
+        size &= PAGE_MASK;
+        add_sysmem_bank(MEMORY_TYPE_CONVENTIONAL, base, base + size);
+}
+
+void * __init early_init_dt_alloc_memory_arch(u64 size, u64 align)
+{
+        return __alloc_bootmem(size, align, 0);
+}
+
+void __init early_init_devtree(void *params)
+{
+        /* Setup flat device-tree pointer */
+        initial_boot_params = params;
+
+        /* Retrieve various informations from the /chosen node of the
+         * device-tree, including the platform type, initrd location and
+         * size, TCE reserve, and more ...
+         */
+        if (!command_line[0])
+                of_scan_flat_dt(early_init_dt_scan_chosen, command_line);
+
+        /* Scan memory nodes and rebuild MEMBLOCKs */
+        of_scan_flat_dt(early_init_dt_scan_root, NULL);
+        if (sysmem.nr_banks == 0)
+                of_scan_flat_dt(early_init_dt_scan_memory, NULL);
+}
+
+static void __init copy_devtree(void)
+{
+        void *alloc = early_init_dt_alloc_memory_arch(
+                        be32_to_cpu(initial_boot_params->totalsize), 0);
+        if (alloc) {
+                memcpy(alloc, initial_boot_params,
+                                be32_to_cpu(initial_boot_params->totalsize));
+                initial_boot_params = alloc;
+        }
+}
+
+static int __init xtensa_device_probe(void)
+{
+        of_platform_populate(NULL, NULL, NULL, NULL);
+        return 0;
+}
+
+device_initcall(xtensa_device_probe);
+
+#endif /* CONFIG_OF */
+
 /*
  * Initialize architecture. (Early stage)
  */
@@ -194,14 +282,14 @@ void __init init_arch(bp_tag_t *bp_start)
 {
         sysmem.nr_banks = 0;
 
-#ifdef CONFIG_CMDLINE_BOOL
-        strcpy(command_line, default_command_line);
-#endif
-
         /* Parse boot parameters */
 
         if (bp_start)
-          parse_bootparam(bp_start);
+                parse_bootparam(bp_start);
+
+#ifdef CONFIG_OF
+        early_init_devtree(dtb_start);
+#endif
 
         if (sysmem.nr_banks == 0) {
                 sysmem.nr_banks = 1;
@@ -210,6 +298,11 @@ void __init init_arch(bp_tag_t *bp_start)
                                      + PLATFORM_DEFAULT_MEM_SIZE;
         }
 
+#ifdef CONFIG_CMDLINE_BOOL
+        if (!command_line[0])
+                strlcpy(command_line, default_command_line, COMMAND_LINE_SIZE);
+#endif
+
         /* Early hook for platforms */
 
         platform_init(bp_start);
@@ -355,11 +448,7 @@ void __init check_s32c1i(void)
 
 void __init setup_arch(char **cmdline_p)
 {
-        extern int mem_reserve(unsigned long, unsigned long, int);
-        extern void bootmem_init(void);
-
-        memcpy(boot_command_line, command_line, COMMAND_LINE_SIZE);
-        boot_command_line[COMMAND_LINE_SIZE-1] = '\0';
+        strlcpy(boot_command_line, command_line, COMMAND_LINE_SIZE);
         *cmdline_p = command_line;
 
         check_s32c1i();
@@ -395,8 +484,12 @@ void __init setup_arch(char **cmdline_p)
 
         bootmem_init();
 
-        platform_setup(cmdline_p);
+#ifdef CONFIG_OF
+        copy_devtree();
+        unflatten_device_tree();
+#endif
 
+        platform_setup(cmdline_p);
 
         paging_init();
         zones_init();