Le 03/09/2019 à 15:04, Segher Boessenkool a écrit :
Hi!
On Tue, Sep 03, 2019 at 03:23:57PM +1000, Alastair D'Silva wrote:
diff --git a/arch/powerpc/mm/mem.c b/arch/powerpc/mm/mem.c
+#if !defined(CONFIG_PPC_8xx) & !defined(CONFIG_PPC64)
Please write that as &&? That is more usual, and thus, easier to read.
+static void flush_dcache_icache_phys(unsigned long physaddr)
+ asm volatile(
+ " mtctr %2;"
+ " mtmsr %3;"
+ " isync;"
+ "0: dcbst 0, %0;"
+ " addi %0, %0, %4;"
+ " bdnz 0b;"
+ " sync;"
+ " mtctr %2;"
+ "1: icbi 0, %1;"
+ " addi %1, %1, %4;"
+ " bdnz 1b;"
+ " sync;"
+ " mtmsr %5;"
+ " isync;"
+ : "+r" (loop1), "+r" (loop2)
+ : "r" (nb), "r" (msr), "i" (bytes), "r" (msr0)
+ : "ctr", "memory");
This outputs as one huge assembler statement, all on one line. That's
going to be fun to read or debug.
Do you mean \n has to be added after the ; ?
loop1 and/or loop2 can be assigned the same register as msr0 or nb. They
need to be made earlyclobbers. (msr is fine, all of its reads are before
any writes to loop1 or loop2; and bytes is fine, it's not a register).
Can you explicit please ? Doesn't '+r' means that they are input and
output at the same time ?
"to be made earlyclobbers", what does this means exactly ? How to do that ?
Christophe
