From 6f3d5d3cc4b1447578ae8484166bbc34a64150c5 Mon Sep 17 00:00:00 2001 From: Michael Ellerman Date: Wed, 16 Aug 2006 22:04:14 +1000 Subject: [POWERPC] Add a helper for calculating RTAS "config_addr" parameters Several RTAS calls take a "config_addr" parameter, which is a particular way of specifying a PCI busno, devfn and register number into a 32-bit word. Currently these are open-coded, and I'll be adding another soon, replace them with a helper that encapsulates the logic. Be more strict about masking the busno too, just in case. Booted on P5 LPAR. Signed-off-by: Michael Ellerman Signed-off-by: Paul Mackerras --- include/asm-powerpc/rtas.h | 16 ++++++++++++++++ 1 file changed, 16 insertions(+) (limited to 'include') diff --git a/include/asm-powerpc/rtas.h b/include/asm-powerpc/rtas.h index 82a27e9a041..d34f9e1f242 100644 --- a/include/asm-powerpc/rtas.h +++ b/include/asm-powerpc/rtas.h @@ -230,5 +230,21 @@ extern unsigned long rtas_rmo_buf; #define GLOBAL_INTERRUPT_QUEUE 9005 +/** + * rtas_config_addr - Format a busno, devfn and reg for RTAS. + * @busno: The bus number. + * @devfn: The device and function number as encoded by PCI_DEVFN(). + * @reg: The register number. + * + * This function encodes the given busno, devfn and register number as + * required for RTAS calls that take a "config_addr" parameter. + * See PAPR requirement 7.3.4-1 for more info. + */ +static inline u32 rtas_config_addr(int busno, int devfn, int reg) +{ + return ((reg & 0xf00) << 20) | ((busno & 0xff) << 16) | + (devfn << 8) | (reg & 0xff); +} + #endif /* __KERNEL__ */ #endif /* _POWERPC_RTAS_H */ -- cgit v1.2.3-70-g09d2