From 55b6332ec89a5fc65d1287708cfd9f06f7a88b90 Mon Sep 17 00:00:00 2001 From: Marcelo Tosatti Date: Sat, 5 Nov 2005 14:06:24 -0200 Subject: [PATCH] ppc32: handle access to non-present IO ports on 8xx This adds exception table entries for I/O instructions on and changes MachineCheckException() slightly to cover 8xx specifics (on 8xx the MCE can be generated while executing the IO access instruction itself, which is not the case on PowerMac's, as the comment on traps.c details). Signed-off-by: Marcelo Tosatti Signed-off-by: Paul Mackerras --- include/asm-ppc/io.h | 12 +++++++----- 1 file changed, 7 insertions(+), 5 deletions(-) (limited to 'include/asm-ppc') diff --git a/include/asm-ppc/io.h b/include/asm-ppc/io.h index f7f614dfc64..2bfdf9c9845 100644 --- a/include/asm-ppc/io.h +++ b/include/asm-ppc/io.h @@ -237,9 +237,9 @@ static inline void __raw_writel(__u32 b, volatile void __iomem *addr) #define outsl(port, buf, nl) _outsl_ns((port)+___IO_BASE, (buf), (nl)) /* - * On powermacs, we will get a machine check exception if we - * try to read data from a non-existent I/O port. Because the - * machine check is an asynchronous exception, it isn't + * On powermacs and 8xx we will get a machine check exception + * if we try to read data from a non-existent I/O port. Because + * the machine check is an asynchronous exception, it isn't * well-defined which instruction SRR0 will point to when the * exception occurs. * With the sequence below (twi; isync; nop), we have found that @@ -258,7 +258,7 @@ extern __inline__ unsigned int name(unsigned int port) \ { \ unsigned int x; \ __asm__ __volatile__( \ - op " %0,0,%1\n" \ + "0:" op " %0,0,%1\n" \ "1: twi 0,%0,0\n" \ "2: isync\n" \ "3: nop\n" \ @@ -269,6 +269,7 @@ extern __inline__ unsigned int name(unsigned int port) \ ".previous\n" \ ".section __ex_table,\"a\"\n" \ " .align 2\n" \ + " .long 0b,5b\n" \ " .long 1b,5b\n" \ " .long 2b,5b\n" \ " .long 3b,5b\n" \ @@ -282,11 +283,12 @@ extern __inline__ unsigned int name(unsigned int port) \ extern __inline__ void name(unsigned int val, unsigned int port) \ { \ __asm__ __volatile__( \ - op " %0,0,%1\n" \ + "0:" op " %0,0,%1\n" \ "1: sync\n" \ "2:\n" \ ".section __ex_table,\"a\"\n" \ " .align 2\n" \ + " .long 0b,2b\n" \ " .long 1b,2b\n" \ ".previous" \ : : "r" (val), "r" (port + ___IO_BASE)); \ -- cgit v1.2.3