[PATCH] powerpc: Kill _machine and hard-coded platform numbers

This removes statically assigned platform numbers and reworks the
powerpc platform probe code to use a better mechanism.  With this,
board support files can simply declare a new machine type with a
macro, and implement a probe() function that uses the flattened
device-tree to detect if they apply for a given machine.

We now have a machine_is() macro that replaces the comparisons of
_machine with the various PLATFORM_* constants.  This commit also
changes various drivers to use the new macro instead of looking at
_machine.

Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Paul Mackerras <paulus@samba.org>

1 files changed, 181 insertions, 200 deletions

diff --git a/arch/powerpc/kernel/vmlinux.lds.S b/arch/powerpc/kernel/vmlinux.lds.S
index 7fa7b15fd8e..fe79c2584cb 100644
--- a/arch/powerpc/kernel/vmlinux.lds.S
+++ b/arch/powerpc/kernel/vmlinux.lds.S
@@ -1,9 +1,11 @@
 #include <linux/config.h>
 #ifdef CONFIG_PPC64
 #include <asm/page.h>
+#define PROVIDE32(x)	PROVIDE(__unused__##x)
 #else
 #define PAGE_SIZE	4096
 #define KERNELBASE	CONFIG_KERNEL_START
+#define PROVIDE32(x)	PROVIDE(x)
 #endif
 #include <asm-generic/vmlinux.lds.h>
 
@@ -18,43 +20,42 @@ jiffies = jiffies_64 + 4;
 #endif
 SECTIONS
 {
-  /* Sections to be discarded. */
-  /DISCARD/ : {
-    *(.exitcall.exit)
-    *(.exit.data)
-  }
-
-  . = KERNELBASE;
-
-  /* Read-only sections, merged into text segment: */
-  .text : {
-    *(.text .text.*)
-    SCHED_TEXT
-    LOCK_TEXT
-    KPROBES_TEXT
-    *(.fixup)
-#ifdef CONFIG_PPC32
-    *(.got1)
-    __got2_start = .;
-    *(.got2)
-    __got2_end = .;
-#else
-    . = ALIGN(PAGE_SIZE);
-    _etext = .;
-#endif
-  }
-#ifdef CONFIG_PPC32
-  _etext = .;
-  PROVIDE (etext = .);
+	/* Sections to be discarded. */
+	/DISCARD/ : {
+	*(.exitcall.exit)
+	*(.exit.data)
+	}
 
-  RODATA
-  .fini      : { *(.fini)    } =0
-  .ctors     : { *(.ctors)   }
-  .dtors     : { *(.dtors)   }
+	. = KERNELBASE;
 
-  .fixup   : { *(.fixup) }
-#endif
+/*
+ * Text, read only data and other permanent read-only sections
+ */
+
+	/* Text and gots */
+	.text : {
+		*(.text .text.*)
+		SCHED_TEXT
+		LOCK_TEXT
+		KPROBES_TEXT
+		*(.fixup)
 
+#ifdef CONFIG_PPC32
+		*(.got1)
+		__got2_start = .;
+		*(.got2)
+		__got2_end = .;
+#endif /* CONFIG_PPC32 */
+
+		. = ALIGN(PAGE_SIZE);
+		_etext = .;
+		PROVIDE32 (etext = .);
+	}
+
+	/* Read-only data */
+	RODATA
+
+	/* Exception & bug tables */
 	__ex_table : {
 		__start___ex_table = .;
 		*(__ex_table)
@@ -67,192 +68,172 @@ SECTIONS
 		__stop___bug_table = .;
 	}
 
-#ifdef CONFIG_PPC64
+/*
+ * Init sections discarded at runtime
+ */
+	. = ALIGN(PAGE_SIZE);
+	__init_begin = .;
+
+	.init.text : {
+		_sinittext = .;
+		*(.init.text)
+		_einittext = .;
+	}
+
+	/* .exit.text is discarded at runtime, not link time,
+	 * to deal with references from __bug_table
+	 */
+	.exit.text : { *(.exit.text) }
+
+	.init.data : {
+		*(.init.data);
+		__vtop_table_begin = .;
+		*(.vtop_fixup);
+		__vtop_table_end = .;
+		__ptov_table_begin = .;
+		*(.ptov_fixup);
+		__ptov_table_end = .;
+	}
+
+	. = ALIGN(16);
+	.init.setup : {
+		__setup_start = .;
+		*(.init.setup)
+		__setup_end = .;
+	}
+
+	.initcall.init : {
+		__initcall_start = .;
+		*(.initcall1.init)
+		*(.initcall2.init)
+		*(.initcall3.init)
+		*(.initcall4.init)
+		*(.initcall5.init)
+		*(.initcall6.init)
+		*(.initcall7.init)
+		__initcall_end = .;
+		}
+
+	.con_initcall.init : {
+		__con_initcall_start = .;
+		*(.con_initcall.init)
+		__con_initcall_end = .;
+	}
+
+	SECURITY_INIT
+
+	. = ALIGN(8);
 	__ftr_fixup : {
 		__start___ftr_fixup = .;
 		*(__ftr_fixup)
 		__stop___ftr_fixup = .;
 	}
 
-  RODATA
-#endif
+	. = ALIGN(PAGE_SIZE);
+	.init.ramfs : {
+		__initramfs_start = .;
+		*(.init.ramfs)
+		__initramfs_end = .;
+	}
 
 #ifdef CONFIG_PPC32
-  /* Read-write section, merged into data segment: */
-  . = ALIGN(PAGE_SIZE);
-  _sdata = .;
-  .data    :
-  {
-    *(.data)
-    *(.data1)
-    *(.sdata)
-    *(.sdata2)
-    *(.got.plt) *(.got)
-    *(.dynamic)
-    CONSTRUCTORS
-  }
-
-  . = ALIGN(PAGE_SIZE);
-  __nosave_begin = .;
-  .data_nosave : { *(.data.nosave) }
-  . = ALIGN(PAGE_SIZE);
-  __nosave_end = .;
-
-  . = ALIGN(32);
-  .data.cacheline_aligned : { *(.data.cacheline_aligned) }
-
-  _edata  =  .;
-  PROVIDE (edata = .);
-
-  . = ALIGN(8192);
-  .data.init_task : { *(.data.init_task) }
+	. = ALIGN(32);
+#else
+	. = ALIGN(128);
 #endif
+	.data.percpu : {
+		__per_cpu_start = .;
+		*(.data.percpu)
+		__per_cpu_end = .;
+	}
 
-  /* will be freed after init */
-  . = ALIGN(PAGE_SIZE);
-  __init_begin = .;
-  .init.text : {
-	_sinittext = .;
-	*(.init.text)
-	_einittext = .;
-  }
-#ifdef CONFIG_PPC32
-  /* .exit.text is discarded at runtime, not link time,
-     to deal with references from __bug_table */
-  .exit.text : { *(.exit.text) }
-#endif
-  .init.data : {
-    *(.init.data);
-    __vtop_table_begin = .;
-    *(.vtop_fixup);
-    __vtop_table_end = .;
-    __ptov_table_begin = .;
-    *(.ptov_fixup);
-    __ptov_table_end = .;
-  }
-
-  . = ALIGN(16);
-  .init.setup : {
-    __setup_start = .;
-    *(.init.setup)
-    __setup_end = .;
-  }
-
-  .initcall.init : {
-	__initcall_start = .;
-	*(.initcall1.init)
-	*(.initcall2.init)
-	*(.initcall3.init)
-	*(.initcall4.init)
-	*(.initcall5.init)
-	*(.initcall6.init)
-	*(.initcall7.init)
-	__initcall_end = .;
-  }
-
-  .con_initcall.init : {
-    __con_initcall_start = .;
-    *(.con_initcall.init)
-    __con_initcall_end = .;
-  }
-
-  SECURITY_INIT
+	. = ALIGN(8);
+	.machine.desc : {
+		__machine_desc_start = . ;
+		*(.machine.desc)
+		__machine_desc_end = . ;
+	}
+
+	/* freed after init ends here */
+	. = ALIGN(PAGE_SIZE);
+	__init_end = .;
+
+/*
+ * And now the various read/write data
+ */
+
+	. = ALIGN(PAGE_SIZE);
+	_sdata = .;
 
 #ifdef CONFIG_PPC32
-  __start___ftr_fixup = .;
-  __ftr_fixup : { *(__ftr_fixup) }
-  __stop___ftr_fixup = .;
+	.data    :
+	{
+		*(.data)
+		*(.sdata)
+		*(.got.plt) *(.got)
+	}
 #else
-  . = ALIGN(PAGE_SIZE);
-  .init.ramfs : {
-    __initramfs_start = .;
-    *(.init.ramfs)
-    __initramfs_end = .;
-  }
-#endif
+	.data : {
+		*(.data .data.rel* .toc1)
+		*(.branch_lt)
+	}
 
-#ifdef CONFIG_PPC32
-  . = ALIGN(32);
+	.opd : {
+		*(.opd)
+	}
+
+	.got : {
+		__toc_start = .;
+		*(.got)
+		*(.toc)
+	}
 #endif
-  .data.percpu : {
-    __per_cpu_start = .;
-    *(.data.percpu)
-    __per_cpu_end = .;
-  }
 
- . = ALIGN(PAGE_SIZE);
-#ifdef CONFIG_PPC64
- . = ALIGN(16384);
- __init_end = .;
- /* freed after init ends here */
-
- /* Read/write sections */
- . = ALIGN(PAGE_SIZE);
- . = ALIGN(16384);
- _sdata = .;
- /* The initial task and kernel stack */
- .data.init_task : {
-      *(.data.init_task)
-      }
-
- . = ALIGN(PAGE_SIZE);
- .data.page_aligned : {
-      *(.data.page_aligned)
-      }
-
- .data.cacheline_aligned : {
-      *(.data.cacheline_aligned)
-      }
-
- .data : {
-      *(.data .data.rel* .toc1)
-      *(.branch_lt)
-      }
-
- .opd : {
-      *(.opd)
-      }
-
- .got : {
-      __toc_start = .;
-      *(.got)
-      *(.toc)
-      . = ALIGN(PAGE_SIZE);
-      _edata = .;
-      }
-
-  . = ALIGN(PAGE_SIZE);
+	. = ALIGN(PAGE_SIZE);
+	_edata  =  .;
+	PROVIDE32 (edata = .);
+
+	/* The initial task and kernel stack */
+#ifdef CONFIG_PPC32
+	. = ALIGN(8192);
 #else
-  __initramfs_start = .;
-  .init.ramfs : {
-    *(.init.ramfs)
-  }
-  __initramfs_end = .;
+	. = ALIGN(16384);
+#endif
+	.data.init_task : {
+		*(.data.init_task)
+	}
 
-  . = ALIGN(4096);
-  __init_end = .;
+	. = ALIGN(PAGE_SIZE);
+	.data.page_aligned : {
+		*(.data.page_aligned)
+	}
 
-  . = ALIGN(4096);
-  _sextratext = .;
-  _eextratext = .;
+	.data.cacheline_aligned : {
+		*(.data.cacheline_aligned)
+	}
 
-  __bss_start = .;
-#endif
+	. = ALIGN(PAGE_SIZE);
+	__data_nosave : {
+		__nosave_begin = .;
+		*(.data.nosave)
+		. = ALIGN(PAGE_SIZE);
+		__nosave_end = .;
+	}
 
-  .bss : {
-    __bss_start = .;
-   *(.sbss) *(.scommon)
-   *(.dynbss)
-   *(.bss)
-   *(COMMON)
-  __bss_stop = .;
-  }
+/*
+ * And finally the bss
+ */
+
+	.bss : {
+		__bss_start = .;
+		*(.sbss) *(.scommon)
+		*(.dynbss)
+		*(.bss)
+		*(COMMON)
+		__bss_stop = .;
+	}
 
-#ifdef CONFIG_PPC64
-  . = ALIGN(PAGE_SIZE);
-#endif
-  _end = . ;
-#ifdef CONFIG_PPC32
-  PROVIDE (end = .);
-#endif
+	. = ALIGN(PAGE_SIZE);
+	_end = . ;
+	PROVIDE32 (end = .);
 }