1 /* 2 * NSC/Cyrix CPU indexed register access. Must be inlined instead of 3 * macros to ensure correct access ordering 4 * Access order is always 0x22 (=offset), 0x23 (=value) 5 * 6 * When using the old macros a line like 7 * setCx86(CX86_CCR2, getCx86(CX86_CCR2) | 0x88); 8 * gets expanded to: 9 * do { 10 * outb((CX86_CCR2), 0x22); 11 * outb((({ 12 * outb((CX86_CCR2), 0x22); 13 * inb(0x23); 14 * }) | 0x88), 0x23); 15 * } while (0); 16 * 17 * which in fact violates the access order (= 0x22, 0x22, 0x23, 0x23). 18 */ 19 20 static inline u8 getCx86(u8 reg) 21 { 22 outb(reg, 0x22); 23 return inb(0x23); 24 } 25 26 static inline void setCx86(u8 reg, u8 data) 27 { 28 outb(reg, 0x22); 29 outb(data, 0x23); 30 } 31 32 #define getCx86_old(reg) ({ outb((reg), 0x22); inb(0x23); }) 33 34 #define setCx86_old(reg, data) do { \ 35 outb((reg), 0x22); \ 36 outb((data), 0x23); \ 37 } while (0) 38 39