diff options
Diffstat (limited to 'include/asm-arm/arch-ixp2000/platform.h')
| -rw-r--r-- | include/asm-arm/arch-ixp2000/platform.h | 54 |
1 files changed, 29 insertions, 25 deletions
diff --git a/include/asm-arm/arch-ixp2000/platform.h b/include/asm-arm/arch-ixp2000/platform.h index c0caf3e3e6fd..a66317ab2071 100644 --- a/include/asm-arm/arch-ixp2000/platform.h +++ b/include/asm-arm/arch-ixp2000/platform.h @@ -15,36 +15,40 @@ #ifndef __ASSEMBLY__ +static inline unsigned long ixp2000_reg_read(volatile void *reg) +{ + return *((volatile unsigned long *)reg); +} + +static inline void ixp2000_reg_write(volatile void *reg, unsigned long val) +{ + *((volatile unsigned long *)reg) = val; +} + /* - * The IXP2400 B0 silicon contains an erratum (#66) that causes writes - * to on-chip I/O register to not complete fully. What this means is - * that if you have a write to on-chip I/O followed by a back-to-back - * read or write, the first write will happen twice. OR...if it's - * not a back-to-back transaction, the read or write will generate - * incorrect data. - * - * The official work around for this is to set the on-chip I/O regions - * as XCB=101 and then force a read-back from the register. + * On the IXP2400, we can't use XCB=000 due to chip bugs. We use + * XCB=101 instead, but that makes all I/O accesses bufferable. This + * is not a problem in general, but we do have to be slightly more + * careful because I/O writes are no longer automatically flushed out + * of the write buffer. * + * In cases where we want to make sure that a write has been flushed + * out of the write buffer before we proceed, for example when masking + * a device interrupt before re-enabling IRQs in CPSR, we can use this + * function, ixp2000_reg_wrb, which performs a write, a readback, and + * issues a dummy instruction dependent on the value of the readback + * (mov rX, rX) to make sure that the readback has completed before we + * continue. */ -#if defined(CONFIG_ARCH_ENP2611) || defined(CONFIG_ARCH_IXDP2400) || defined(CONFIG_ARCH_IXDP2401) +static inline void ixp2000_reg_wrb(volatile void *reg, unsigned long val) +{ + unsigned long dummy; -#include <asm/system.h> /* Pickup local_irq_ functions */ + *((volatile unsigned long *)reg) = val; -static inline void ixp2000_reg_write(volatile unsigned long *reg, unsigned long val) -{ - volatile unsigned long dummy; - unsigned long flags; - - local_irq_save(flags); - *reg = val; - barrier(); - dummy = *reg; - local_irq_restore(flags); + dummy = *((volatile unsigned long *)reg); + __asm__ __volatile__("mov %0, %0" : "+r" (dummy)); } -#else -#define ixp2000_reg_write(reg, val) (*reg = val) -#endif /* IXDP2400 || IXDP2401 */ /* * Boards may multiplex different devices on the 2nd channel of @@ -84,7 +88,7 @@ void ixp2000_release_slowport(struct slowport_cfg *); */ static inline unsigned ixp2000_has_broken_slowport(void) { - unsigned long id = *IXP2000_PROD_ID; + unsigned long id = *IXP2000_PRODUCT_ID; unsigned long id_prod = id & (IXP2000_MAJ_PROD_TYPE_MASK | IXP2000_MIN_PROD_TYPE_MASK); return (((id_prod == |