From 1ad4af852bc3b352ac36ceffd2e30dbba413bc1a Mon Sep 17 00:00:00 2001 From: Jayachandran C Date: Sat, 23 Mar 2013 17:27:57 +0000 Subject: [PATCH] MIPS: Netlogic: Add 32-bit support for XLP Update asm/netlogic/haldefs.h to extend register access functions nlm_{read,write}_reg64() for 32-bit compilation. When compiled for 32-bit the functions will read 64 IO registers with interrupts disabled. Signed-off-by: Jayachandran C Patchwork: http://patchwork.linux-mips.org/patch/5026/ Acked-by: John Crispin --- arch/mips/include/asm/netlogic/haldefs.h | 56 ++++++++++++++++++++++++++++---- 1 file changed, 50 insertions(+), 6 deletions(-) diff --git a/arch/mips/include/asm/netlogic/haldefs.h b/arch/mips/include/asm/netlogic/haldefs.h index 419d8ae..61fecb8 100644 --- a/arch/mips/include/asm/netlogic/haldefs.h +++ b/arch/mips/include/asm/netlogic/haldefs.h @@ -35,14 +35,13 @@ #ifndef __NLM_HAL_HALDEFS_H__ #define __NLM_HAL_HALDEFS_H__ +#include /* for local_irq_disable */ + /* * This file contains platform specific memory mapped IO implementation * and will provide a way to read 32/64 bit memory mapped registers in * all ABIs */ -#if !defined(CONFIG_64BIT) && defined(CONFIG_CPU_XLP) -#error "o32 compile not supported on XLP yet" -#endif /* * For o32 compilation, we have to disable interrupts and enable KX bit to * access 64 bit addresses or data. @@ -87,13 +86,40 @@ nlm_write_reg(uint64_t base, uint32_t reg, uint32_t val) *addr = val; } +/* + * For o32 compilation, we have to disable interrupts to access 64 bit + * registers + * + * We need to disable interrupts because we save just the lower 32 bits of + * registers in interrupt handling. So if we get hit by an interrupt while + * using the upper 32 bits of a register, we lose. + */ + static inline uint64_t nlm_read_reg64(uint64_t base, uint32_t reg) { uint64_t addr = base + (reg >> 1) * sizeof(uint64_t); volatile uint64_t *ptr = (volatile uint64_t *)(long)addr; - - return *ptr; + uint64_t val; + + if (sizeof(unsigned long) == 4) { + unsigned long flags; + + local_irq_save(flags); + __asm__ __volatile__( + ".set push" "\n\t" + ".set mips64" "\n\t" + "ld %L0, %1" "\n\t" + "dsra32 %M0, %L0, 0" "\n\t" + "sll %L0, %L0, 0" "\n\t" + ".set pop" "\n" + : "=r" (val) + : "m" (*ptr)); + local_irq_restore(flags); + } else + val = *ptr; + + return val; } static inline void @@ -102,7 +128,25 @@ nlm_write_reg64(uint64_t base, uint32_t reg, uint64_t val) uint64_t addr = base + (reg >> 1) * sizeof(uint64_t); volatile uint64_t *ptr = (volatile uint64_t *)(long)addr; - *ptr = val; + if (sizeof(unsigned long) == 4) { + unsigned long flags; + uint64_t tmp; + + local_irq_save(flags); + __asm__ __volatile__( + ".set push" "\n\t" + ".set mips64" "\n\t" + "dsll32 %L0, %L0, 0" "\n\t" + "dsrl32 %L0, %L0, 0" "\n\t" + "dsll32 %M0, %M0, 0" "\n\t" + "or %L0, %L0, %M0" "\n\t" + "sd %L0, %2" "\n\t" + ".set pop" "\n" + : "=r" (tmp) + : "0" (val), "m" (*ptr)); + local_irq_restore(flags); + } else + *ptr = val; } /* -- 2.7.4