Merge branch 'x86-olpc-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip

* 'x86-olpc-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip:
  x86, olpc: Constify an olpc_ofw() arg
  x86, olpc: Use pr_debug() for EC commands
  x86, olpc: Add comment about implicit optimization barrier
  x86, olpc: Add support for calling into OpenFirmware

5 files changed, 127 insertions, 12 deletions

diff --git a/arch/x86/kernel/Makefile b/arch/x86/kernel/Makefile
index e77b220..0925676 100644
--- a/arch/x86/kernel/Makefile
+++ b/arch/x86/kernel/Makefile
@@ -104,6 +104,7 @@ obj-$(CONFIG_SCx200)		+= scx200.o
 scx200-y			+= scx200_32.o
 
 obj-$(CONFIG_OLPC)		+= olpc.o
+obj-$(CONFIG_OLPC_OPENFIRMWARE)	+= olpc_ofw.o
 obj-$(CONFIG_X86_MRST)		+= mrst.o
 
 microcode-y				:= microcode_core.o
diff --git a/arch/x86/kernel/head_32.S b/arch/x86/kernel/head_32.S
index 37c3d4b..ff4c453 100644
--- a/arch/x86/kernel/head_32.S
+++ b/arch/x86/kernel/head_32.S
@@ -131,6 +131,12 @@ ENTRY(startup_32)
 	movsl
 1:
 
+#ifdef CONFIG_OLPC_OPENFIRMWARE
+	/* save OFW's pgdir table for later use when calling into OFW */
+	movl %cr3, %eax
+	movl %eax, pa(olpc_ofw_pgd)
+#endif
+
 #ifdef CONFIG_PARAVIRT
 	/* This is can only trip for a broken bootloader... */
 	cmpw $0x207, pa(boot_params + BP_version)
diff --git a/arch/x86/kernel/olpc.c b/arch/x86/kernel/olpc.c
index 8297160..0e0cdde 100644
--- a/arch/x86/kernel/olpc.c
+++ b/arch/x86/kernel/olpc.c
@@ -21,10 +21,7 @@
 #include <asm/geode.h>
 #include <asm/setup.h>
 #include <asm/olpc.h>
-
-#ifdef CONFIG_OPEN_FIRMWARE
-#include <asm/ofw.h>
-#endif
+#include <asm/olpc_ofw.h>
 
 struct olpc_platform_t olpc_platform_info;
 EXPORT_SYMBOL_GPL(olpc_platform_info);
@@ -145,7 +142,7 @@ restart:
 	 * The OBF flag will sometimes misbehave due to what we believe
 	 * is a hardware quirk..
 	 */
-	printk(KERN_DEBUG "olpc-ec:  running cmd 0x%x\n", cmd);
+	pr_devel("olpc-ec:  running cmd 0x%x\n", cmd);
 	outb(cmd, 0x6c);
 
 	if (wait_on_ibf(0x6c, 0)) {
@@ -162,8 +159,7 @@ restart:
 						" EC accept data!\n");
 				goto err;
 			}
-			printk(KERN_DEBUG "olpc-ec:  sending cmd arg 0x%x\n",
-					inbuf[i]);
+			pr_devel("olpc-ec:  sending cmd arg 0x%x\n", inbuf[i]);
 			outb(inbuf[i], 0x68);
 		}
 	}
@@ -176,8 +172,7 @@ restart:
 				goto restart;
 			}
 			outbuf[i] = inb(0x68);
-			printk(KERN_DEBUG "olpc-ec:  received 0x%x\n",
-					outbuf[i]);
+			pr_devel("olpc-ec:  received 0x%x\n", outbuf[i]);
 		}
 	}
 
@@ -188,14 +183,15 @@ err:
 }
 EXPORT_SYMBOL_GPL(olpc_ec_cmd);
 
-#ifdef CONFIG_OPEN_FIRMWARE
+#ifdef CONFIG_OLPC_OPENFIRMWARE
 static void __init platform_detect(void)
 {
 	size_t propsize;
 	__be32 rev;
+	const void *args[] = { NULL, "board-revision-int", &rev, (void *)4 };
+	void *res[] = { &propsize };
 
-	if (ofw("getprop", 4, 1, NULL, "board-revision-int", &rev, 4,
-			&propsize) || propsize != 4) {
+	if (olpc_ofw("getprop", args, res) || propsize != 4) {
 		printk(KERN_ERR "ofw: getprop call failed!\n");
 		rev = cpu_to_be32(0);
 	}
diff --git a/arch/x86/kernel/olpc_ofw.c b/arch/x86/kernel/olpc_ofw.c
new file mode 100644
index 0000000..3218aa7
--- /dev/null
+++ b/arch/x86/kernel/olpc_ofw.c
@@ -0,0 +1,106 @@
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/init.h>
+#include <asm/page.h>
+#include <asm/setup.h>
+#include <asm/io.h>
+#include <asm/pgtable.h>
+#include <asm/olpc_ofw.h>
+
+/* address of OFW callback interface; will be NULL if OFW isn't found */
+static int (*olpc_ofw_cif)(int *);
+
+/* page dir entry containing OFW's pgdir table; filled in by head_32.S */
+u32 olpc_ofw_pgd __initdata;
+
+static DEFINE_SPINLOCK(ofw_lock);
+
+#define MAXARGS 10
+
+void __init setup_olpc_ofw_pgd(void)
+{
+	pgd_t *base, *ofw_pde;
+
+	if (!olpc_ofw_cif)
+		return;
+
+	/* fetch OFW's PDE */
+	base = early_ioremap(olpc_ofw_pgd, sizeof(olpc_ofw_pgd) * PTRS_PER_PGD);
+	if (!base) {
+		printk(KERN_ERR "failed to remap OFW's pgd - disabling OFW!\n");
+		olpc_ofw_cif = NULL;
+		return;
+	}
+	ofw_pde = &base[OLPC_OFW_PDE_NR];
+
+	/* install OFW's PDE permanently into the kernel's pgtable */
+	set_pgd(&swapper_pg_dir[OLPC_OFW_PDE_NR], *ofw_pde);
+	/* implicit optimization barrier here due to uninline function return */
+
+	early_iounmap(base, sizeof(olpc_ofw_pgd) * PTRS_PER_PGD);
+}
+
+int __olpc_ofw(const char *name, int nr_args, const void **args, int nr_res,
+		void **res)
+{
+	int ofw_args[MAXARGS + 3];
+	unsigned long flags;
+	int ret, i, *p;
+
+	BUG_ON(nr_args + nr_res > MAXARGS);
+
+	if (!olpc_ofw_cif)
+		return -EIO;
+
+	ofw_args[0] = (int)name;
+	ofw_args[1] = nr_args;
+	ofw_args[2] = nr_res;
+
+	p = &ofw_args[3];
+	for (i = 0; i < nr_args; i++, p++)
+		*p = (int)args[i];
+
+	/* call into ofw */
+	spin_lock_irqsave(&ofw_lock, flags);
+	ret = olpc_ofw_cif(ofw_args);
+	spin_unlock_irqrestore(&ofw_lock, flags);
+
+	if (!ret) {
+		for (i = 0; i < nr_res; i++, p++)
+			*((int *)res[i]) = *p;
+	}
+
+	return ret;
+}
+EXPORT_SYMBOL_GPL(__olpc_ofw);
+
+/* OFW cif _should_ be above this address */
+#define OFW_MIN 0xff000000
+
+/* OFW starts on a 1MB boundary */
+#define OFW_BOUND (1<<20)
+
+void __init olpc_ofw_detect(void)
+{
+	struct olpc_ofw_header *hdr = &boot_params.olpc_ofw_header;
+	unsigned long start;
+
+	/* ensure OFW booted us by checking for "OFW " string */
+	if (hdr->ofw_magic != OLPC_OFW_SIG)
+		return;
+
+	olpc_ofw_cif = (int (*)(int *))hdr->cif_handler;
+
+	if ((unsigned long)olpc_ofw_cif < OFW_MIN) {
+		printk(KERN_ERR "OFW detected, but cif has invalid address 0x%lx - disabling.\n",
+				(unsigned long)olpc_ofw_cif);
+		olpc_ofw_cif = NULL;
+		return;
+	}
+
+	/* determine where OFW starts in memory */
+	start = round_down((unsigned long)olpc_ofw_cif, OFW_BOUND);
+	printk(KERN_INFO "OFW detected in memory, cif @ 0x%lx (reserving top %ldMB)\n",
+			(unsigned long)olpc_ofw_cif, (-start) >> 20);
+	reserve_top_address(-start);
+}
diff --git a/arch/x86/kernel/setup.c b/arch/x86/kernel/setup.c
index b4ae4ac..b008e78 100644
--- a/arch/x86/kernel/setup.c
+++ b/arch/x86/kernel/setup.c
@@ -102,6 +102,7 @@
 
 #include <asm/paravirt.h>
 #include <asm/hypervisor.h>
+#include <asm/olpc_ofw.h>
 
 #include <asm/percpu.h>
 #include <asm/topology.h>
@@ -736,10 +737,15 @@ void __init setup_arch(char **cmdline_p)
 	/* VMI may relocate the fixmap; do this before touching ioremap area */
 	vmi_init();
 
+	/* OFW also may relocate the fixmap */
+	olpc_ofw_detect();
+
 	early_trap_init();
 	early_cpu_init();
 	early_ioremap_init();
 
+	setup_olpc_ofw_pgd();
+
 	ROOT_DEV = old_decode_dev(boot_params.hdr.root_dev);
 	screen_info = boot_params.screen_info;
 	edid_info = boot_params.edid_info;