Re: [PATCH v4 04/16] powerpc/mm/32s: use generic mmu_mapin_ram() for all blocks.

[Christophe Leroy]

On 02/21/2019 01:51 PM, Michael Ellerman wrote:
> Christophe Leroy <christophe.leroy@xxxxxx> writes:
>
> > Now that mmu_mapin_ram() is able to handle other blocks
> > than the one starting at 0, the WII can use it for all
> > its blocks.
> >
> > Signed-off-by: Christophe Leroy <christophe.leroy@xxxxxx>
> > ---
> >   arch/powerpc/mm/pgtable_32.c | 27 +++++++++------------------
> >   1 file changed, 9 insertions(+), 18 deletions(-)
> >
> > diff --git a/arch/powerpc/mm/pgtable_32.c b/arch/powerpc/mm/pgtable_32.c
> > index b4858818523f..2bf9bf8867d4 100644
> > --- a/arch/powerpc/mm/pgtable_32.c
> > +++ b/arch/powerpc/mm/pgtable_32.c
> > @@ -254,26 +254,17 @@ static void __init __mapin_ram_chunk(unsigned long offset, unsigned long top)
> >   
> >   void __init mapin_ram(void)
> >   {
> > -	unsigned long s, top;
> > -
> > -#ifndef CONFIG_WII
> > -	top = total_lowmem;
> > -	s = mmu_mapin_ram(0, top);
> > -	__mapin_ram_chunk(s, top);
> > -#else
> > -	if (!wii_hole_size) {
> > -		s = mmu_mapin_ram(0, total_lowmem);
> > -		__mapin_ram_chunk(s, total_lowmem);
> > -	} else {
> > -		top = wii_hole_start;
> > -		s = mmu_mapin_ram(0, top);
> > -		__mapin_ram_chunk(s, top);
> > +	struct memblock_region *reg;
> > +
> > +	for_each_memblock(memory, reg) {
> > +		unsigned long base = reg->base;
> > +		unsigned long top = min(base + reg->size, (unsigned long)total_lowmem);
>
> This gives me:
>
> In file included from ../arch/powerpc/mm/pgtable_32.c:22:
> ../arch/powerpc/mm/pgtable_32.c: In function âmapin_ramâ:
> ../include/linux/kernel.h:846:29: error: comparison of distinct pointer types lacks a cast [-Werror]
>     (!!(sizeof((typeof(x) *)1 == (typeof(y) *)1)))
>                               ^~
> ../include/linux/kernel.h:860:4: note: in expansion of macro â__typecheckâ
>     (__typecheck(x, y) && __no_side_effects(x, y))
>      ^~~~~~~~~~~
> ../include/linux/kernel.h:870:24: note: in expansion of macro â__safe_cmpâ
>    __builtin_choose_expr(__safe_cmp(x, y), \
>                          ^~~~~~~~~~
> ../include/linux/kernel.h:879:19: note: in expansion of macro â__careful_cmpâ
>   #define min(x, y) __careful_cmp(x, y, <)
>                     ^~~~~~~~~~~~~
> ../arch/powerpc/mm/pgtable_32.c:261:23: note: in expansion of macro âminâ
>     unsigned long top = min(base + reg->size, (unsigned long)total_lowmem);
>                         ^~~
> cc1: all warnings being treated as errors
> ../scripts/Makefile.build:276: recipe for target 'arch/powerpc/mm/pgtable_32.o' failed
>
>
> For 44x/bamboo_defconfig.

The patch below should make it. Tested it on half a dozen of config.

diff --git a/arch/powerpc/mm/pgtable_32.c b/arch/powerpc/mm/pgtable_32.c
index 2bf9bf8867d4..c4b0eb51f6d8 100644
--- a/arch/powerpc/mm/pgtable_32.c
+++ b/arch/powerpc/mm/pgtable_32.c
@@ -257,8 +257,8 @@ void __init mapin_ram(void)
 	struct memblock_region *reg;

 	for_each_memblock(memory, reg) {
-		unsigned long base = reg->base;
-		unsigned long top = min(base + reg->size, (unsigned long)total_lowmem);
+		phys_addr_t base = reg->base;
+		phys_addr_t top = min(base + reg->size, total_lowmem);

 		if (base >= top)
 			continue;

I'll send out v5, hope it'll be the last one :(

Christophe