[PATCH 15/19] ppc64: Move iSeries initrd logic into device tree

[Michael Ellerman]

Move iSeries initrd logic earlier and store the result in the device tree
so generic code can do the rest for us.

The iSeries code had a "feature" which the generic code lacks, ie. if the
initrd is bigger than the configured ram disk size, we make the ram disk size
big enough - I've copied the code across but I'm not sure if we want to keep
it.

---

 arch/ppc64/kernel/iSeries_setup.c |   43 ++++++++++----------------------------
 arch/ppc64/kernel/setup.c         |    8 ++++++-
 2 files changed, 19 insertions(+), 32 deletions(-)

Index: work/arch/ppc64/kernel/iSeries_setup.c
===================================================================
--- work.orig/arch/ppc64/kernel/iSeries_setup.c
+++ work/arch/ppc64/kernel/iSeries_setup.c
@@ -24,7 +24,6 @@
 #include <linux/smp.h>
 #include <linux/param.h>
 #include <linux/string.h>
-#include <linux/initrd.h>
 #include <linux/seq_file.h>
 #include <linux/kdev_t.h>
 #include <linux/major.h>
@@ -95,7 +94,6 @@ static unsigned long tbFreqMhzHundreths;
 
 int piranha_simulator;
 
-extern int rd_size;		/* Defined in drivers/block/rd.c */
 extern unsigned long klimit;
 extern unsigned long embedded_sysmap_start;
 extern unsigned long embedded_sysmap_end;
@@ -319,24 +317,6 @@ static void __init iSeries_init_early(vo
 
 	ppc64_interrupt_controller = IC_ISERIES;
 
-#if defined(CONFIG_BLK_DEV_INITRD)
-	/*
-	 * If the init RAM disk has been configured and there is
-	 * a non-zero starting address for it, set it up
-	 */
-	if (naca.xRamDisk) {
-		initrd_start = (unsigned long)__va(naca.xRamDisk);
-		initrd_end = initrd_start + naca.xRamDiskSize * PAGE_SIZE;
-		initrd_below_start_ok = 1;	// ramdisk in kernel space
-		ROOT_DEV = Root_RAM0;
-		if (((rd_size * 1024) / PAGE_SIZE) < naca.xRamDiskSize)
-			rd_size = (naca.xRamDiskSize * PAGE_SIZE) / 1024;
-	} else
-#endif /* CONFIG_BLK_DEV_INITRD */
-	{
-	    /* ROOT_DEV = MKDEV(VIODASD_MAJOR, 1); */
-	}
-
 	iSeries_recal_tb = get_tb();
 	iSeries_recal_titan = HvCallXm_loadTod();
 
@@ -370,17 +350,6 @@ static void __init iSeries_init_early(vo
 	mf_initialized = 1;
 	mb();
 
-	/* If we were passed an initrd, set the ROOT_DEV properly if the values
-	 * look sensible. If not, clear initrd reference.
-	 */
-#ifdef CONFIG_BLK_DEV_INITRD
-	if (initrd_start >= KERNELBASE && initrd_end >= KERNELBASE &&
-	    initrd_end > initrd_start)
-		ROOT_DEV = Root_RAM0;
-	else
-		initrd_start = initrd_end = 0;
-#endif /* CONFIG_BLK_DEV_INITRD */
-
 	DBG(" <- iSeries_init_early()\n");
 }
 
@@ -1067,6 +1036,17 @@ void dt_model(struct iseries_flat_dt *dt
 	dt_prop_str(dt, "compatible", "IBM,iSeries");
 }
 
+void dt_initrd(struct iseries_flat_dt *dt)
+{
+#ifdef CONFIG_BLK_DEV_INITRD
+	if (naca.xRamDisk) {
+		dt_prop_u64(dt, "linux,initrd-start", (u64)naca.xRamDisk);
+		dt_prop_u64(dt, "linux,initrd-end",
+			(u64)naca.xRamDisk + naca.xRamDiskSize * PAGE_SIZE);
+	}
+#endif
+}
+
 void build_flat_dt(struct iseries_flat_dt *dt)
 {
 	u64 tmp[2];
@@ -1094,6 +1074,7 @@ void build_flat_dt(struct iseries_flat_d
 	dt_prop_str(dt, "bootargs", cmd_line);
 	if (iseries_memory_limit)
 		dt_prop_u64(dt, "linux,memory-limit", iseries_memory_limit);
+	dt_initrd(dt);
 
 	dt_end_node(dt);
 
Index: work/arch/ppc64/kernel/setup.c
===================================================================
--- work.orig/arch/ppc64/kernel/setup.c
+++ work/arch/ppc64/kernel/setup.c
@@ -534,6 +534,7 @@ static void __init check_for_initrd(void
 {
 #ifdef CONFIG_BLK_DEV_INITRD
 	u64 *prop;
+	extern int rd_size;	/* Defined in drivers/block/rd.c */
 
 	DBG(" -> check_for_initrd()\n");
 
@@ -557,8 +558,13 @@ static void __init check_for_initrd(void
 	else
 		initrd_start = initrd_end = 0;
 
+	/* XXX This came from iSeries code, make sure ram disk is big enough */
+	if ((rd_size * 1024) < (initrd_end - initrd_start))
+		rd_size = (initrd_end - initrd_start) / 1024;
+
 	if (initrd_start)
-		printk("Found initrd at 0x%lx:0x%lx\n", initrd_start, initrd_end);
+		printk("Found initrd at 0x%lx:0x%lx\n", initrd_start,
+				initrd_end);
 
 	DBG(" <- check_for_initrd()\n");
 #endif /* CONFIG_BLK_DEV_INITRD */