[RFC PATCH v2 0/4] powerpc: wii: mem2 as ram support

[RFC PATCH v2 0/4] powerpc: wii: mem2 as ram support

[Albert Herranz]

The following patches add a series of workarounds to allow the use of
the second 64MB RAM block (MEM2) as normal memory on the Nintendo Wii
video game console.
Without these workarounds that portion of memory can't be used as it
is non-contiguous to the first memory block, and this is currently
unsupported on the PowerPC architecture for 32-bit systems.

This series complement the "powerpc: nintendo wii support" series.

Albert Herranz (4):
  wii: bootwrapper: add fixup to calc useable mem2
  wii: use both mem1 and mem2 as ram
  powerpc: allow ioremap within reserved memory regions
  powerpc: wii: allow ioremap within the memory hole

 arch/powerpc/boot/wii.c                  |  118 +++++++++++++++++++++++++++++-
 arch/powerpc/mm/init_32.c                |    9 ++
 arch/powerpc/mm/mmu_decl.h               |   11 +++-
 arch/powerpc/mm/pgtable_32.c             |   36 ++++++++-
 arch/powerpc/mm/ppc_mmu_32.c             |    4 +-
 arch/powerpc/platforms/embedded6xx/wii.c |   66 +++++++++++++++++
 include/linux/lmb.h                      |    1 +
 lib/lmb.c                                |    7 ++-
 8 files changed, 240 insertions(+), 12 deletions(-)

[RFC PATCH v2 1/4] wii: bootwrapper: add fixup to calc useable mem2

[Albert Herranz]

The top portion of MEM2 (the second 64MB memory block) in the Nintendo
Wii video game console is used by the firmware running on the Starlet
processor.

Add code to calculate the portion of MEM2 safely useable by the
Broadway processor. When running under the 'mini' firmware this is
easily determined from an in-memory header. Otherwise, a safe default
is used.

Signed-off-by: Albert Herranz <albert_herranz@yahoo.es>
---
 arch/powerpc/boot/wii.c |  118 +++++++++++++++++++++++++++++++++++++++++++++-
 1 files changed, 115 insertions(+), 3 deletions(-)

diff --git a/arch/powerpc/boot/wii.c b/arch/powerpc/boot/wii.c
index d0e2625..2ebaec0 100644
--- a/arch/powerpc/boot/wii.c
+++ b/arch/powerpc/boot/wii.c
@@ -22,10 +22,120 @@
 
 BSS_STACK(8192);
 
-#define HW_REG(x)	((void *)(x))
+#define HW_REG(x)		((void *)(x))
 
-#define EXI_CTRL	HW_REG(0x0d800070)
-#define EXI_CTRL_ENABLE	(1<<0)
+#define EXI_CTRL		HW_REG(0x0d800070)
+#define EXI_CTRL_ENABLE		(1<<0)
+
+#define MEM2_TOP		(0x10000000 + 64*1024*1024)
+#define FIRMWARE_DEFAULT_SIZE	(12*1024*1024)
+
+
+struct mipc_infohdr {
+	char magic[3];
+	u8 version;
+	u32 mem2_boundary;
+	u32 ipc_in;
+	size_t ipc_in_size;
+	u32 ipc_out;
+	size_t ipc_out_size;
+};
+
+static int mipc_check_address(u32 pa)
+{
+	/* only MEM2 addresses */
+	if (pa < 0x10000000 || pa > 0x14000000)
+		return -EINVAL;
+	return 0;
+}
+
+static struct mipc_infohdr *mipc_get_infohdr(void)
+{
+	struct mipc_infohdr **hdrp, *hdr;
+
+	/* 'mini' header pointer is the last word of MEM2 memory */
+	hdrp = (struct mipc_infohdr **)0x13fffffc;
+	if (mipc_check_address((u32)hdrp)) {
+		printf("mini: invalid hdrp %08X\n", (u32)hdrp);
+		hdr = NULL;
+		goto out;
+	}
+
+	hdr = *hdrp;
+	if (mipc_check_address((u32)hdr)) {
+		printf("mini: invalid hdr %08X\n", (u32)hdr);
+		hdr = NULL;
+		goto out;
+	}
+	if (memcmp(hdr->magic, "IPC", 3)) {
+		printf("mini: invalid magic\n");
+		hdr = NULL;
+		goto out;
+	}
+
+out:
+	return hdr;
+}
+
+static int mipc_get_mem2_boundary(u32 *mem2_boundary)
+{
+	struct mipc_infohdr *hdr;
+	int error;
+
+	hdr = mipc_get_infohdr();
+	if (!hdr) {
+		error = -1;
+		goto out;
+	}
+
+	if (mipc_check_address(hdr->mem2_boundary)) {
+		printf("mini: invalid mem2_boundary %08X\n",
+		       hdr->mem2_boundary);
+		error = -EINVAL;
+		goto out;
+	}
+	*mem2_boundary = hdr->mem2_boundary;
+	error = 0;
+out:
+	return error;
+
+}
+
+static void platform_fixups(void)
+{
+	void *mem;
+	u32 reg[4];
+	u32 mem2_boundary;
+	int len;
+	int error;
+
+	mem = finddevice("/memory");
+	if (!mem)
+		fatal("Can't find memory node\n");
+
+	/* two ranges of (address, size) words */
+	len = getprop(mem, "reg", reg, sizeof(reg));
+	if (len != sizeof(reg)) {
+		/* nothing to do */
+		goto out;
+	}
+
+	/* retrieve MEM2 boundary from 'mini' */
+	error = mipc_get_mem2_boundary(&mem2_boundary);
+	if (error) {
+		/* if that fails use a sane value */
+		mem2_boundary = MEM2_TOP - FIRMWARE_DEFAULT_SIZE;
+	}
+
+	if (mem2_boundary > reg[2] && mem2_boundary < reg[2] + reg[3]) {
+		reg[3] = mem2_boundary - reg[2];
+		printf("top of MEM2 @ %08X\n", reg[2] + reg[3]);
+		setprop(mem, "reg", reg, sizeof(reg));
+	}
+
+out:
+	return;
+}
 
 void platform_init(unsigned long r3, unsigned long r4, unsigned long r5)
 {
@@ -42,5 +152,7 @@ void platform_init(unsigned long r3, unsigned long r4, unsigned long r5)
 
 	if (ug_probe())
 		console_ops.write = ug_console_write;
+
+	platform_ops.fixups = platform_fixups;
 }
 
-- 
1.6.3.3

Re: [RFC PATCH v2 1/4] wii: bootwrapper: add fixup to calc useable mem2

[Benjamin Herrenschmidt]

On Tue, 2009-12-08 at 19:43 +0100, Albert Herranz wrote:
> The top portion of MEM2 (the second 64MB memory block) in the Nintendo
> Wii video game console is used by the firmware running on the Starlet
> processor.
> 
> Add code to calculate the portion of MEM2 safely useable by the
> Broadway processor. When running under the 'mini' firmware this is
> easily determined from an in-memory header. Otherwise, a safe default
> is used.
> 
> Signed-off-by: Albert Herranz <albert_herranz@yahoo.es>

Acked-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>

> ---
>  arch/powerpc/boot/wii.c |  118 +++++++++++++++++++++++++++++++++++++++++++++-
>  1 files changed, 115 insertions(+), 3 deletions(-)
> 
> diff --git a/arch/powerpc/boot/wii.c b/arch/powerpc/boot/wii.c
> index d0e2625..2ebaec0 100644
> --- a/arch/powerpc/boot/wii.c
> +++ b/arch/powerpc/boot/wii.c
> @@ -22,10 +22,120 @@
>  
>  BSS_STACK(8192);
>  
> -#define HW_REG(x)	((void *)(x))
> +#define HW_REG(x)		((void *)(x))
>  
> -#define EXI_CTRL	HW_REG(0x0d800070)
> -#define EXI_CTRL_ENABLE	(1<<0)
> +#define EXI_CTRL		HW_REG(0x0d800070)
> +#define EXI_CTRL_ENABLE		(1<<0)
> +
> +#define MEM2_TOP		(0x10000000 + 64*1024*1024)
> +#define FIRMWARE_DEFAULT_SIZE	(12*1024*1024)
> +
> +
> +struct mipc_infohdr {
> +	char magic[3];
> +	u8 version;
> +	u32 mem2_boundary;
> +	u32 ipc_in;
> +	size_t ipc_in_size;
> +	u32 ipc_out;
> +	size_t ipc_out_size;
> +};
> +
> +static int mipc_check_address(u32 pa)
> +{
> +	/* only MEM2 addresses */
> +	if (pa < 0x10000000 || pa > 0x14000000)
> +		return -EINVAL;
> +	return 0;
> +}
> +
> +static struct mipc_infohdr *mipc_get_infohdr(void)
> +{
> +	struct mipc_infohdr **hdrp, *hdr;
> +
> +	/* 'mini' header pointer is the last word of MEM2 memory */
> +	hdrp = (struct mipc_infohdr **)0x13fffffc;
> +	if (mipc_check_address((u32)hdrp)) {
> +		printf("mini: invalid hdrp %08X\n", (u32)hdrp);
> +		hdr = NULL;
> +		goto out;
> +	}
> +
> +	hdr = *hdrp;
> +	if (mipc_check_address((u32)hdr)) {
> +		printf("mini: invalid hdr %08X\n", (u32)hdr);
> +		hdr = NULL;
> +		goto out;
> +	}
> +	if (memcmp(hdr->magic, "IPC", 3)) {
> +		printf("mini: invalid magic\n");
> +		hdr = NULL;
> +		goto out;
> +	}
> +
> +out:
> +	return hdr;
> +}
> +
> +static int mipc_get_mem2_boundary(u32 *mem2_boundary)
> +{
> +	struct mipc_infohdr *hdr;
> +	int error;
> +
> +	hdr = mipc_get_infohdr();
> +	if (!hdr) {
> +		error = -1;
> +		goto out;
> +	}
> +
> +	if (mipc_check_address(hdr->mem2_boundary)) {
> +		printf("mini: invalid mem2_boundary %08X\n",
> +		       hdr->mem2_boundary);
> +		error = -EINVAL;
> +		goto out;
> +	}
> +	*mem2_boundary = hdr->mem2_boundary;
> +	error = 0;
> +out:
> +	return error;
> +
> +}
> +
> +static void platform_fixups(void)
> +{
> +	void *mem;
> +	u32 reg[4];
> +	u32 mem2_boundary;
> +	int len;
> +	int error;
> +
> +	mem = finddevice("/memory");
> +	if (!mem)
> +		fatal("Can't find memory node\n");
> +
> +	/* two ranges of (address, size) words */
> +	len = getprop(mem, "reg", reg, sizeof(reg));
> +	if (len != sizeof(reg)) {
> +		/* nothing to do */
> +		goto out;
> +	}
> +
> +	/* retrieve MEM2 boundary from 'mini' */
> +	error = mipc_get_mem2_boundary(&mem2_boundary);
> +	if (error) {
> +		/* if that fails use a sane value */
> +		mem2_boundary = MEM2_TOP - FIRMWARE_DEFAULT_SIZE;
> +	}
> +
> +	if (mem2_boundary > reg[2] && mem2_boundary < reg[2] + reg[3]) {
> +		reg[3] = mem2_boundary - reg[2];
> +		printf("top of MEM2 @ %08X\n", reg[2] + reg[3]);
> +		setprop(mem, "reg", reg, sizeof(reg));
> +	}
> +
> +out:
> +	return;
> +}
>  
>  void platform_init(unsigned long r3, unsigned long r4, unsigned long r5)
>  {
> @@ -42,5 +152,7 @@ void platform_init(unsigned long r3, unsigned long r4, unsigned long r5)
>  
>  	if (ug_probe())
>  		console_ops.write = ug_console_write;
> +
> +	platform_ops.fixups = platform_fixups;
>  }
>  

[RFC PATCH v2 2/4] wii: use both mem1 and mem2 as ram

[Albert Herranz]

Signed-off-by: Albert Herranz <albert_herranz@yahoo.es>
---
 arch/powerpc/mm/init_32.c                |    4 ++
 arch/powerpc/mm/mmu_decl.h               |   10 ++++-
 arch/powerpc/mm/pgtable_32.c             |   32 +++++++++++++--
 arch/powerpc/mm/ppc_mmu_32.c             |    4 +-
 arch/powerpc/platforms/embedded6xx/wii.c |   63 ++++++++++++++++++++++++++++++
 5 files changed, 106 insertions(+), 7 deletions(-)

diff --git a/arch/powerpc/mm/init_32.c b/arch/powerpc/mm/init_32.c
index 9ddcfb4..703c7c2 100644
--- a/arch/powerpc/mm/init_32.c
+++ b/arch/powerpc/mm/init_32.c
@@ -131,9 +131,13 @@ void __init MMU_init(void)
 	MMU_setup();
 
 	if (lmb.memory.cnt > 1) {
+#ifndef CONFIG_WII
 		lmb.memory.cnt = 1;
 		lmb_analyze();
 		printk(KERN_WARNING "Only using first contiguous memory region");
+#else
+		wii_memory_fixups();
+#endif
 	}
 
 	total_lowmem = total_memory = lmb_end_of_DRAM() - memstart_addr;
diff --git a/arch/powerpc/mm/mmu_decl.h b/arch/powerpc/mm/mmu_decl.h
index d2e5321..9aa39fe 100644
--- a/arch/powerpc/mm/mmu_decl.h
+++ b/arch/powerpc/mm/mmu_decl.h
@@ -136,6 +136,14 @@ extern phys_addr_t total_lowmem;
 extern phys_addr_t memstart_addr;
 extern phys_addr_t lowmem_end_addr;
 
+#ifdef CONFIG_WII
+extern unsigned long wii_hole_start;
+extern unsigned long wii_hole_size;
+
+extern unsigned long wii_mmu_mapin_mem2(unsigned long top);
+extern void wii_memory_fixups(void);
+#endif
+
 /* ...and now those things that may be slightly different between processor
  * architectures.  -- Dan
  */
@@ -155,5 +163,5 @@ extern void adjust_total_lowmem(void);
 #elif defined(CONFIG_PPC32)
 /* anything 32-bit except 4xx or 8xx */
 extern void MMU_init_hw(void);
-extern unsigned long mmu_mapin_ram(void);
+extern unsigned long mmu_mapin_ram(unsigned long top);
 #endif
diff --git a/arch/powerpc/mm/pgtable_32.c b/arch/powerpc/mm/pgtable_32.c
index cb96cb2..b55bbe8 100644
--- a/arch/powerpc/mm/pgtable_32.c
+++ b/arch/powerpc/mm/pgtable_32.c
@@ -283,18 +283,18 @@ int map_page(unsigned long va, phys_addr_t pa, int flags)
 }
 
 /*
- * Map in a big chunk of physical memory starting at PAGE_OFFSET.
+ * Map in a chunk of physical memory starting at start.
  */
-void __init mapin_ram(void)
+void __init __mapin_ram_chunk(unsigned long offset, unsigned long top)
 {
 	unsigned long v, s, f;
 	phys_addr_t p;
 	int ktext;
 
-	s = mmu_mapin_ram();
+	s = offset;
 	v = PAGE_OFFSET + s;
 	p = memstart_addr + s;
-	for (; s < total_lowmem; s += PAGE_SIZE) {
+	for (; s < top; s += PAGE_SIZE) {
 		ktext = ((char *) v >= _stext && (char *) v < etext);
 		f = ktext ? PAGE_KERNEL_TEXT : PAGE_KERNEL;
 		map_page(v, p, f);
@@ -307,6 +307,30 @@ void __init mapin_ram(void)
 	}
 }
 
+void __init mapin_ram(void)
+{
+	unsigned long s, top;
+
+#ifndef CONFIG_WII
+	top = total_lowmem;
+	s = mmu_mapin_ram(top);
+	__mapin_ram_chunk(s, top);
+#else
+	if (!wii_hole_size) {
+		s = mmu_mapin_ram(total_lowmem);
+		__mapin_ram_chunk(s, total_lowmem);
+	} else {
+		top = wii_hole_start;
+		s = mmu_mapin_ram(top);
+		__mapin_ram_chunk(s, top);
+
+		top = lmb_end_of_DRAM();
+		s = wii_mmu_mapin_mem2(top);
+		__mapin_ram_chunk(s, top);
+	}
+#endif
+}
+
 /* Scan the real Linux page tables and return a PTE pointer for
  * a virtual address in a context.
  * Returns true (1) if PTE was found, zero otherwise.  The pointer to
diff --git a/arch/powerpc/mm/ppc_mmu_32.c b/arch/powerpc/mm/ppc_mmu_32.c
index 2d2a87e..f11c2cd 100644
--- a/arch/powerpc/mm/ppc_mmu_32.c
+++ b/arch/powerpc/mm/ppc_mmu_32.c
@@ -72,7 +72,7 @@ unsigned long p_mapped_by_bats(phys_addr_t pa)
 	return 0;
 }
 
-unsigned long __init mmu_mapin_ram(void)
+unsigned long __init mmu_mapin_ram(unsigned long top)
 {
 	unsigned long tot, bl, done;
 	unsigned long max_size = (256<<20);
@@ -86,7 +86,7 @@ unsigned long __init mmu_mapin_ram(void)
 
 	/* Make sure we don't map a block larger than the
 	   smallest alignment of the physical address. */
-	tot = total_lowmem;
+	tot = top;
 	for (bl = 128<<10; bl < max_size; bl <<= 1) {
 		if (bl * 2 > tot)
 			break;
diff --git a/arch/powerpc/platforms/embedded6xx/wii.c b/arch/powerpc/platforms/embedded6xx/wii.c
index 1bd41cc..5eaed86 100644
--- a/arch/powerpc/platforms/embedded6xx/wii.c
+++ b/arch/powerpc/platforms/embedded6xx/wii.c
@@ -20,6 +20,8 @@
 #include <linux/seq_file.h>
 #include <linux/kexec.h>
 #include <linux/of_platform.h>
+#include <linux/lmb.h>
+#include <mm/mmu_decl.h>
 
 #include <asm/io.h>
 #include <asm/machdep.h>
@@ -52,6 +54,67 @@
 static void __iomem *hw_ctrl;
 static void __iomem *hw_gpio;
 
+unsigned long wii_hole_start;
+unsigned long wii_hole_size;
+
+
+static int page_aligned(unsigned long x)
+{
+	return !(x & (PAGE_SIZE-1));
+}
+
+void __init wii_memory_fixups(void)
+{
+	struct lmb_property *p = lmb.memory.region;
+
+	/*
+	 * This is part of a workaround to allow the use of two
+	 * discontiguous RAM ranges on the Wii, even if this is
+	 * currently unsupported on 32-bit PowerPC Linux.
+	 *
+	 * We coealesce the two memory ranges of the Wii into a
+	 * single range, then create a reservation for the "hole"
+	 * between both ranges.
+	 */
+
+	BUG_ON(lmb.memory.cnt != 2);
+	BUG_ON(!page_aligned(p[0].base) || !page_aligned(p[1].base));
+
+	p[0].size = _ALIGN_DOWN(p[0].size, PAGE_SIZE);
+	p[1].size = _ALIGN_DOWN(p[1].size, PAGE_SIZE);
+
+	wii_hole_start = p[0].base + p[0].size;
+	wii_hole_size = p[1].base - wii_hole_start;
+
+	pr_info("MEM1: <%08llx %08llx>\n", p[0].base, p[0].size);
+	pr_info("HOLE: <%08lx %08lx>\n", wii_hole_start, wii_hole_size);
+	pr_info("MEM2: <%08llx %08llx>\n", p[1].base, p[1].size);
+
+	p[0].size += wii_hole_size + p[1].size;
+
+	lmb.memory.cnt = 1;
+	lmb_analyze();
+
+	/* reserve the hole */
+	lmb_reserve(wii_hole_start, wii_hole_size);
+}
+
+unsigned long __init wii_mmu_mapin_mem2(unsigned long top)
+{
+	unsigned long delta, size, bl;
+	unsigned long max_size = (256<<20);
+
+	/* MEM2 64MB@0x10000000 */
+	delta = wii_hole_start + wii_hole_size;
+	size = top - delta;
+	for (bl = 128<<10; bl < max_size; bl <<= 1) {
+		if (bl * 2 > size)
+			break;
+	}
+	setbat(4, PAGE_OFFSET+delta, delta, bl, PAGE_KERNEL_X);
+	return delta + bl;
+}
+
 static void wii_spin(void)
 {
 	local_irq_disable();
-- 
1.6.3.3

Re: [RFC PATCH v2 2/4] wii: use both mem1 and mem2 as ram

[Benjamin Herrenschmidt]

On Tue, 2009-12-08 at 19:43 +0100, Albert Herranz wrote:
> Signed-off-by: Albert Herranz <albert_herranz@yahoo.es>

Acked-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>

That will do for now. At some stage somebody should look at getting
proper sparsemem etc... working (or even normal linear memmap with a
hole which isn't actually hard but will waste a bit of RAM).

Cheers,
Ben.

> ---
>  arch/powerpc/mm/init_32.c                |    4 ++
>  arch/powerpc/mm/mmu_decl.h               |   10 ++++-
>  arch/powerpc/mm/pgtable_32.c             |   32 +++++++++++++--
>  arch/powerpc/mm/ppc_mmu_32.c             |    4 +-
>  arch/powerpc/platforms/embedded6xx/wii.c |   63 ++++++++++++++++++++++++++++++
>  5 files changed, 106 insertions(+), 7 deletions(-)
> 
> diff --git a/arch/powerpc/mm/init_32.c b/arch/powerpc/mm/init_32.c
> index 9ddcfb4..703c7c2 100644
> --- a/arch/powerpc/mm/init_32.c
> +++ b/arch/powerpc/mm/init_32.c
> @@ -131,9 +131,13 @@ void __init MMU_init(void)
>  	MMU_setup();
>  
>  	if (lmb.memory.cnt > 1) {
> +#ifndef CONFIG_WII
>  		lmb.memory.cnt = 1;
>  		lmb_analyze();
>  		printk(KERN_WARNING "Only using first contiguous memory region");
> +#else
> +		wii_memory_fixups();
> +#endif
>  	}
>  
>  	total_lowmem = total_memory = lmb_end_of_DRAM() - memstart_addr;
> diff --git a/arch/powerpc/mm/mmu_decl.h b/arch/powerpc/mm/mmu_decl.h
> index d2e5321..9aa39fe 100644
> --- a/arch/powerpc/mm/mmu_decl.h
> +++ b/arch/powerpc/mm/mmu_decl.h
> @@ -136,6 +136,14 @@ extern phys_addr_t total_lowmem;
>  extern phys_addr_t memstart_addr;
>  extern phys_addr_t lowmem_end_addr;
>  
> +#ifdef CONFIG_WII
> +extern unsigned long wii_hole_start;
> +extern unsigned long wii_hole_size;
> +
> +extern unsigned long wii_mmu_mapin_mem2(unsigned long top);
> +extern void wii_memory_fixups(void);
> +#endif
> +
>  /* ...and now those things that may be slightly different between processor
>   * architectures.  -- Dan
>   */
> @@ -155,5 +163,5 @@ extern void adjust_total_lowmem(void);
>  #elif defined(CONFIG_PPC32)
>  /* anything 32-bit except 4xx or 8xx */
>  extern void MMU_init_hw(void);
> -extern unsigned long mmu_mapin_ram(void);
> +extern unsigned long mmu_mapin_ram(unsigned long top);
>  #endif
> diff --git a/arch/powerpc/mm/pgtable_32.c b/arch/powerpc/mm/pgtable_32.c
> index cb96cb2..b55bbe8 100644
> --- a/arch/powerpc/mm/pgtable_32.c
> +++ b/arch/powerpc/mm/pgtable_32.c
> @@ -283,18 +283,18 @@ int map_page(unsigned long va, phys_addr_t pa, int flags)
>  }
>  
>  /*
> - * Map in a big chunk of physical memory starting at PAGE_OFFSET.
> + * Map in a chunk of physical memory starting at start.
>   */
> -void __init mapin_ram(void)
> +void __init __mapin_ram_chunk(unsigned long offset, unsigned long top)
>  {
>  	unsigned long v, s, f;
>  	phys_addr_t p;
>  	int ktext;
>  
> -	s = mmu_mapin_ram();
> +	s = offset;
>  	v = PAGE_OFFSET + s;
>  	p = memstart_addr + s;
> -	for (; s < total_lowmem; s += PAGE_SIZE) {
> +	for (; s < top; s += PAGE_SIZE) {
>  		ktext = ((char *) v >= _stext && (char *) v < etext);
>  		f = ktext ? PAGE_KERNEL_TEXT : PAGE_KERNEL;
>  		map_page(v, p, f);
> @@ -307,6 +307,30 @@ void __init mapin_ram(void)
>  	}
>  }
>  
> +void __init mapin_ram(void)
> +{
> +	unsigned long s, top;
> +
> +#ifndef CONFIG_WII
> +	top = total_lowmem;
> +	s = mmu_mapin_ram(top);
> +	__mapin_ram_chunk(s, top);
> +#else
> +	if (!wii_hole_size) {
> +		s = mmu_mapin_ram(total_lowmem);
> +		__mapin_ram_chunk(s, total_lowmem);
> +	} else {
> +		top = wii_hole_start;
> +		s = mmu_mapin_ram(top);
> +		__mapin_ram_chunk(s, top);
> +
> +		top = lmb_end_of_DRAM();
> +		s = wii_mmu_mapin_mem2(top);
> +		__mapin_ram_chunk(s, top);
> +	}
> +#endif
> +}
> +
>  /* Scan the real Linux page tables and return a PTE pointer for
>   * a virtual address in a context.
>   * Returns true (1) if PTE was found, zero otherwise.  The pointer to
> diff --git a/arch/powerpc/mm/ppc_mmu_32.c b/arch/powerpc/mm/ppc_mmu_32.c
> index 2d2a87e..f11c2cd 100644
> --- a/arch/powerpc/mm/ppc_mmu_32.c
> +++ b/arch/powerpc/mm/ppc_mmu_32.c
> @@ -72,7 +72,7 @@ unsigned long p_mapped_by_bats(phys_addr_t pa)
>  	return 0;
>  }
>  
> -unsigned long __init mmu_mapin_ram(void)
> +unsigned long __init mmu_mapin_ram(unsigned long top)
>  {
>  	unsigned long tot, bl, done;
>  	unsigned long max_size = (256<<20);
> @@ -86,7 +86,7 @@ unsigned long __init mmu_mapin_ram(void)
>  
>  	/* Make sure we don't map a block larger than the
>  	   smallest alignment of the physical address. */
> -	tot = total_lowmem;
> +	tot = top;
>  	for (bl = 128<<10; bl < max_size; bl <<= 1) {
>  		if (bl * 2 > tot)
>  			break;
> diff --git a/arch/powerpc/platforms/embedded6xx/wii.c b/arch/powerpc/platforms/embedded6xx/wii.c
> index 1bd41cc..5eaed86 100644
> --- a/arch/powerpc/platforms/embedded6xx/wii.c
> +++ b/arch/powerpc/platforms/embedded6xx/wii.c
> @@ -20,6 +20,8 @@
>  #include <linux/seq_file.h>
>  #include <linux/kexec.h>
>  #include <linux/of_platform.h>
> +#include <linux/lmb.h>
> +#include <mm/mmu_decl.h>
>  
>  #include <asm/io.h>
>  #include <asm/machdep.h>
> @@ -52,6 +54,67 @@
>  static void __iomem *hw_ctrl;
>  static void __iomem *hw_gpio;
>  
> +unsigned long wii_hole_start;
> +unsigned long wii_hole_size;
> +
> +
> +static int page_aligned(unsigned long x)
> +{
> +	return !(x & (PAGE_SIZE-1));
> +}
> +
> +void __init wii_memory_fixups(void)
> +{
> +	struct lmb_property *p = lmb.memory.region;
> +
> +	/*
> +	 * This is part of a workaround to allow the use of two
> +	 * discontiguous RAM ranges on the Wii, even if this is
> +	 * currently unsupported on 32-bit PowerPC Linux.
> +	 *
> +	 * We coealesce the two memory ranges of the Wii into a
> +	 * single range, then create a reservation for the "hole"
> +	 * between both ranges.
> +	 */
> +
> +	BUG_ON(lmb.memory.cnt != 2);
> +	BUG_ON(!page_aligned(p[0].base) || !page_aligned(p[1].base));
> +
> +	p[0].size = _ALIGN_DOWN(p[0].size, PAGE_SIZE);
> +	p[1].size = _ALIGN_DOWN(p[1].size, PAGE_SIZE);
> +
> +	wii_hole_start = p[0].base + p[0].size;
> +	wii_hole_size = p[1].base - wii_hole_start;
> +
> +	pr_info("MEM1: <%08llx %08llx>\n", p[0].base, p[0].size);
> +	pr_info("HOLE: <%08lx %08lx>\n", wii_hole_start, wii_hole_size);
> +	pr_info("MEM2: <%08llx %08llx>\n", p[1].base, p[1].size);
> +
> +	p[0].size += wii_hole_size + p[1].size;
> +
> +	lmb.memory.cnt = 1;
> +	lmb_analyze();
> +
> +	/* reserve the hole */
> +	lmb_reserve(wii_hole_start, wii_hole_size);
> +}
> +
> +unsigned long __init wii_mmu_mapin_mem2(unsigned long top)
> +{
> +	unsigned long delta, size, bl;
> +	unsigned long max_size = (256<<20);
> +
> +	/* MEM2 64MB@0x10000000 */
> +	delta = wii_hole_start + wii_hole_size;
> +	size = top - delta;
> +	for (bl = 128<<10; bl < max_size; bl <<= 1) {
> +		if (bl * 2 > size)
> +			break;
> +	}
> +	setbat(4, PAGE_OFFSET+delta, delta, bl, PAGE_KERNEL_X);
> +	return delta + bl;
> +}
> +
>  static void wii_spin(void)
>  {
>  	local_irq_disable();

[RFC PATCH v2 3/4] powerpc: allow ioremap within reserved memory regions

[Albert Herranz]

Signed-off-by: Albert Herranz <albert_herranz@yahoo.es>
---
v1 -> v2
- use a run-time flag to allow/disallow remapping reserved regions
- use lmbs to determine reserved regions

 arch/powerpc/mm/init_32.c    |    5 +++++
 arch/powerpc/mm/mmu_decl.h   |    1 +
 arch/powerpc/mm/pgtable_32.c |    4 +++-
 include/linux/lmb.h          |    1 +
 lib/lmb.c                    |    7 ++++++-
 5 files changed, 16 insertions(+), 2 deletions(-)

diff --git a/arch/powerpc/mm/init_32.c b/arch/powerpc/mm/init_32.c
index 703c7c2..4ec900a 100644
--- a/arch/powerpc/mm/init_32.c
+++ b/arch/powerpc/mm/init_32.c
@@ -82,6 +82,11 @@ extern struct task_struct *current_set[NR_CPUS];
 int __map_without_bats;
 int __map_without_ltlbs;
 
+/*
+ * This tells the system to allow ioremapping memory marked as reserved.
+ */
+int __allow_ioremap_reserved;
+
 /* max amount of low RAM to map in */
 unsigned long __max_low_memory = MAX_LOW_MEM;
 
diff --git a/arch/powerpc/mm/mmu_decl.h b/arch/powerpc/mm/mmu_decl.h
index 9aa39fe..34dacc3 100644
--- a/arch/powerpc/mm/mmu_decl.h
+++ b/arch/powerpc/mm/mmu_decl.h
@@ -115,6 +115,7 @@ extern void settlbcam(int index, unsigned long virt, phys_addr_t phys,
 extern void invalidate_tlbcam_entry(int index);
 
 extern int __map_without_bats;
+extern int __allow_ioremap_reserved;
 extern unsigned long ioremap_base;
 extern unsigned int rtas_data, rtas_size;
 
diff --git a/arch/powerpc/mm/pgtable_32.c b/arch/powerpc/mm/pgtable_32.c
index b55bbe8..177e403 100644
--- a/arch/powerpc/mm/pgtable_32.c
+++ b/arch/powerpc/mm/pgtable_32.c
@@ -26,6 +26,7 @@
 #include <linux/vmalloc.h>
 #include <linux/init.h>
 #include <linux/highmem.h>
+#include <linux/lmb.h>
 
 #include <asm/pgtable.h>
 #include <asm/pgalloc.h>
@@ -191,7 +192,8 @@ __ioremap_caller(phys_addr_t addr, unsigned long size, unsigned long flags,
 	 * Don't allow anybody to remap normal RAM that we're using.
 	 * mem_init() sets high_memory so only do the check after that.
 	 */
-	if (mem_init_done && (p < virt_to_phys(high_memory))) {
+	if (mem_init_done && (p < virt_to_phys(high_memory)) &&
+	    !(__allow_ioremap_reserved && lmb_is_region_reserved(p, size))) {
 		printk("__ioremap(): phys addr 0x%llx is RAM lr %p\n",
 		       (unsigned long long)p, __builtin_return_address(0));
 		return NULL;
diff --git a/include/linux/lmb.h b/include/linux/lmb.h
index 2442e3f..ef82b8f 100644
--- a/include/linux/lmb.h
+++ b/include/linux/lmb.h
@@ -54,6 +54,7 @@ extern u64 __init lmb_phys_mem_size(void);
 extern u64 lmb_end_of_DRAM(void);
 extern void __init lmb_enforce_memory_limit(u64 memory_limit);
 extern int __init lmb_is_reserved(u64 addr);
+extern int lmb_is_region_reserved(u64 base, u64 size);
 extern int lmb_find(struct lmb_property *res);
 
 extern void lmb_dump_all(void);
diff --git a/lib/lmb.c b/lib/lmb.c
index 0343c05..9cee171 100644
--- a/lib/lmb.c
+++ b/lib/lmb.c
@@ -263,7 +263,7 @@ long __init lmb_reserve(u64 base, u64 size)
 	return lmb_add_region(_rgn, base, size);
 }
 
-long __init lmb_overlaps_region(struct lmb_region *rgn, u64 base, u64 size)
+long lmb_overlaps_region(struct lmb_region *rgn, u64 base, u64 size)
 {
 	unsigned long i;
 
@@ -493,6 +493,11 @@ int __init lmb_is_reserved(u64 addr)
 	return 0;
 }
 
+int lmb_is_region_reserved(u64 base, u64 size)
+{
+	return lmb_overlaps_region(&lmb.reserved, base, size);
+}
+
 /*
  * Given a <base, len>, find which memory regions belong to this range.
  * Adjust the request and return a contiguous chunk.
-- 
1.6.3.3

Re: [RFC PATCH v2 3/4] powerpc: allow ioremap within reserved memory regions

[Benjamin Herrenschmidt]

On Tue, 2009-12-08 at 19:43 +0100, Albert Herranz wrote:
> Signed-off-by: Albert Herranz <albert_herranz@yahoo.es>

Acked-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>

> ---
> v1 -> v2
> - use a run-time flag to allow/disallow remapping reserved regions
> - use lmbs to determine reserved regions

We won't need that once we fix proper discontig mem.

BTW. Question: Why do we need that fixup of yours to fold the 2 LMBs
into one ?

Wouldn't it be easier just to keep the 2 LMBs ? You already fix the
mapin_ram thingy, so you could easily fix it up to just iterate over the
LMBs instead no ? For now, it could only BAT map the first LMB to
simplify things and we can fix the BAT mapping for the second one in a
second step too.

Wouldn't that work with simpler code ? An in the case of ioremap, the
test becomes simply to check if it's RAM by checking if it's in the LMB
rather than if it's reserved, which should be easier and wouldn't
require your flag to "enable" the tweak since it could perfectly be kept
as standard behaviour

Also the code in arch/powerpc/mm/mem.c will already deal with holes
just fine and will pass the hole size information to the VM which should
make it behave properly.

Thus I have the feeling that keeping the 2 LMBs rather than coalescing
would simplify the code basically by only requiring a small fixup of the
maping RAM bit.

I'm acking the patches for now, so you can always come up with a fixup
on top of them and we can merge the current ones.


>  arch/powerpc/mm/init_32.c    |    5 +++++
>  arch/powerpc/mm/mmu_decl.h   |    1 +
>  arch/powerpc/mm/pgtable_32.c |    4 +++-
>  include/linux/lmb.h          |    1 +
>  lib/lmb.c                    |    7 ++++++-
>  5 files changed, 16 insertions(+), 2 deletions(-)
> 
> diff --git a/arch/powerpc/mm/init_32.c b/arch/powerpc/mm/init_32.c
> index 703c7c2..4ec900a 100644
> --- a/arch/powerpc/mm/init_32.c
> +++ b/arch/powerpc/mm/init_32.c
> @@ -82,6 +82,11 @@ extern struct task_struct *current_set[NR_CPUS];
>  int __map_without_bats;
>  int __map_without_ltlbs;
>  
> +/*
> + * This tells the system to allow ioremapping memory marked as reserved.
> + */
> +int __allow_ioremap_reserved;
> +
>  /* max amount of low RAM to map in */
>  unsigned long __max_low_memory = MAX_LOW_MEM;
>  
> diff --git a/arch/powerpc/mm/mmu_decl.h b/arch/powerpc/mm/mmu_decl.h
> index 9aa39fe..34dacc3 100644
> --- a/arch/powerpc/mm/mmu_decl.h
> +++ b/arch/powerpc/mm/mmu_decl.h
> @@ -115,6 +115,7 @@ extern void settlbcam(int index, unsigned long virt, phys_addr_t phys,
>  extern void invalidate_tlbcam_entry(int index);
>  
>  extern int __map_without_bats;
> +extern int __allow_ioremap_reserved;
>  extern unsigned long ioremap_base;
>  extern unsigned int rtas_data, rtas_size;
>  
> diff --git a/arch/powerpc/mm/pgtable_32.c b/arch/powerpc/mm/pgtable_32.c
> index b55bbe8..177e403 100644
> --- a/arch/powerpc/mm/pgtable_32.c
> +++ b/arch/powerpc/mm/pgtable_32.c
> @@ -26,6 +26,7 @@
>  #include <linux/vmalloc.h>
>  #include <linux/init.h>
>  #include <linux/highmem.h>
> +#include <linux/lmb.h>
>  
>  #include <asm/pgtable.h>
>  #include <asm/pgalloc.h>
> @@ -191,7 +192,8 @@ __ioremap_caller(phys_addr_t addr, unsigned long size, unsigned long flags,
>  	 * Don't allow anybody to remap normal RAM that we're using.
>  	 * mem_init() sets high_memory so only do the check after that.
>  	 */
> -	if (mem_init_done && (p < virt_to_phys(high_memory))) {
> +	if (mem_init_done && (p < virt_to_phys(high_memory)) &&
> +	    !(__allow_ioremap_reserved && lmb_is_region_reserved(p, size))) {
>  		printk("__ioremap(): phys addr 0x%llx is RAM lr %p\n",
>  		       (unsigned long long)p, __builtin_return_address(0));
>  		return NULL;
> diff --git a/include/linux/lmb.h b/include/linux/lmb.h
> index 2442e3f..ef82b8f 100644
> --- a/include/linux/lmb.h
> +++ b/include/linux/lmb.h
> @@ -54,6 +54,7 @@ extern u64 __init lmb_phys_mem_size(void);
>  extern u64 lmb_end_of_DRAM(void);
>  extern void __init lmb_enforce_memory_limit(u64 memory_limit);
>  extern int __init lmb_is_reserved(u64 addr);
> +extern int lmb_is_region_reserved(u64 base, u64 size);
>  extern int lmb_find(struct lmb_property *res);
>  
>  extern void lmb_dump_all(void);
> diff --git a/lib/lmb.c b/lib/lmb.c
> index 0343c05..9cee171 100644
> --- a/lib/lmb.c
> +++ b/lib/lmb.c
> @@ -263,7 +263,7 @@ long __init lmb_reserve(u64 base, u64 size)
>  	return lmb_add_region(_rgn, base, size);
>  }
>  
> -long __init lmb_overlaps_region(struct lmb_region *rgn, u64 base, u64 size)
> +long lmb_overlaps_region(struct lmb_region *rgn, u64 base, u64 size)
>  {
>  	unsigned long i;
>  
> @@ -493,6 +493,11 @@ int __init lmb_is_reserved(u64 addr)
>  	return 0;
>  }
>  
> +int lmb_is_region_reserved(u64 base, u64 size)
> +{
> +	return lmb_overlaps_region(&lmb.reserved, base, size);
> +}
> +
>  /*
>   * Given a <base, len>, find which memory regions belong to this range.
>   * Adjust the request and return a contiguous chunk.

Re: [RFC PATCH v2 3/4] powerpc: allow ioremap within reserved memory regions

[Albert Herranz]

Benjamin Herrenschmidt wrote:
> On Tue, 2009-12-08 at 19:43 +0100, Albert Herranz wrote:
>> Signed-off-by: Albert Herranz <albert_herranz@yahoo.es>
> 
> Acked-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
> 
>> ---
>> v1 -> v2
>> - use a run-time flag to allow/disallow remapping reserved regions
>> - use lmbs to determine reserved regions
> 
> We won't need that once we fix proper discontig mem.
> 
> BTW. Question: Why do we need that fixup of yours to fold the 2 LMBs
> into one ?
> 
> Wouldn't it be easier just to keep the 2 LMBs ? You already fix the
> mapin_ram thingy, so you could easily fix it up to just iterate over the
> LMBs instead no ? For now, it could only BAT map the first LMB to
> simplify things and we can fix the BAT mapping for the second one in a
> second step too.
> 
> Wouldn't that work with simpler code ? An in the case of ioremap, the
> test becomes simply to check if it's RAM by checking if it's in the LMB
> rather than if it's reserved, which should be easier and wouldn't
> require your flag to "enable" the tweak since it could perfectly be kept
> as standard behaviour
> 
> Also the code in arch/powerpc/mm/mem.c will already deal with holes
> just fine and will pass the hole size information to the VM which should
> make it behave properly.
> 
> Thus I have the feeling that keeping the 2 LMBs rather than coalescing
> would simplify the code basically by only requiring a small fixup of the
> maping RAM bit.
> 
> I'm acking the patches for now, so you can always come up with a fixup
> on top of them and we can merge the current ones.
> 

I'll look into this.
I used a single lmb range just as the current code does to avoid any unwanted side effects as I didn't audit all the mm code.

Thanks,
Albert

Re: [RFC PATCH v2 3/4] powerpc: allow ioremap within reserved memory regions

[Benjamin Herrenschmidt]

On Sat, 2009-12-12 at 01:33 +0100, Albert Herranz wrote:
> 
> I'll look into this.
> I used a single lmb range just as the current code does to avoid any
> unwanted side effects as I didn't audit all the mm code.

Well, I -may- be missing something ... but I think outside of the setup
of the initial mapping, we should be fine. Well, you'll tell me if I'm
wrong here :-)

Cheers,
Ben.

[RFC PATCH v2 4/4] powerpc: wii: allow ioremap within the memory hole

[Albert Herranz]

Signed-off-by: Albert Herranz <albert_herranz@yahoo.es>
---
 arch/powerpc/platforms/embedded6xx/wii.c |    3 +++
 1 files changed, 3 insertions(+), 0 deletions(-)

diff --git a/arch/powerpc/platforms/embedded6xx/wii.c b/arch/powerpc/platforms/embedded6xx/wii.c
index 5eaed86..0df8a91 100644
--- a/arch/powerpc/platforms/embedded6xx/wii.c
+++ b/arch/powerpc/platforms/embedded6xx/wii.c
@@ -97,6 +97,9 @@ void __init wii_memory_fixups(void)
 
 	/* reserve the hole */
 	lmb_reserve(wii_hole_start, wii_hole_size);
+
+	/* allow ioremapping the address space in the hole */
+	__allow_ioremap_reserved = 1;
 }
 
 unsigned long __init wii_mmu_mapin_mem2(unsigned long top)
-- 
1.6.3.3

Re: [RFC PATCH v2 4/4] powerpc: wii: allow ioremap within the memory hole

[Benjamin Herrenschmidt]

On Tue, 2009-12-08 at 19:43 +0100, Albert Herranz wrote:
> Signed-off-by: Albert Herranz <albert_herranz@yahoo.es>
> ---
>  arch/powerpc/platforms/embedded6xx/wii.c |    3 +++
>  1 files changed, 3 insertions(+), 0 deletions(-)

Acked-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>

> diff --git a/arch/powerpc/platforms/embedded6xx/wii.c b/arch/powerpc/platforms/embedded6xx/wii.c
> index 5eaed86..0df8a91 100644
> --- a/arch/powerpc/platforms/embedded6xx/wii.c
> +++ b/arch/powerpc/platforms/embedded6xx/wii.c
> @@ -97,6 +97,9 @@ void __init wii_memory_fixups(void)
>  
>  	/* reserve the hole */
>  	lmb_reserve(wii_hole_start, wii_hole_size);
> +
> +	/* allow ioremapping the address space in the hole */
> +	__allow_ioremap_reserved = 1;
>  }
>  
>  unsigned long __init wii_mmu_mapin_mem2(unsigned long top)