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/* SPDX-License-Identifier: GPL-2.0 */
/*
* NSC/Cyrix CPU indexed register access. Must be inlined instead of
* macros to ensure correct access ordering
* Access order is always 0x22 (=offset), 0x23 (=value)
*
* When using the old macros a line like
* setCx86(CX86_CCR2, getCx86(CX86_CCR2) | 0x88);
* gets expanded to:
* do {
* outb((CX86_CCR2), 0x22);
* outb((({
* outb((CX86_CCR2), 0x22);
* inb(0x23);
* }) | 0x88), 0x23);
* } while (0);
*
* which in fact violates the access order (= 0x22, 0x22, 0x23, 0x23).
*/
static inline u8 getCx86(u8 reg)
{
outb(reg, 0x22);
return inb(0x23);
}
static inline void setCx86(u8 reg, u8 data)
{
outb(reg, 0x22);
outb(data, 0x23);
}
#define getCx86_old(reg) ({ outb((reg), 0x22); inb(0x23); })
#define setCx86_old(reg, data) do { \
outb((reg), 0x22); \
outb((data), 0x23); \
} while (0)
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