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/* SPDX-License-Identifier: GPL-2.0 */
#ifndef _ASM_X86_CPUID_LEAF_0x2_API_H
#define _ASM_X86_CPUID_LEAF_0x2_API_H
#include <asm/cpuid/api.h>
#include <asm/cpuid/types.h>
/**
* cpuid_get_leaf_0x2_regs() - Return sanitized leaf 0x2 register output
* @regs: Output parameter
*
* Query CPUID leaf 0x2 and store its output in @regs. Force set any
* invalid 1-byte descriptor returned by the hardware to zero (the NULL
* cache/TLB descriptor) before returning it to the caller.
*
* Use for_each_leaf_0x2_entry() to iterate over the register output in
* parsed form.
*/
static inline void cpuid_get_leaf_0x2_regs(union leaf_0x2_regs *regs)
{
cpuid_leaf(0x2, regs);
/*
* All Intel CPUs must report an iteration count of 1. In case
* of bogus hardware, treat all returned descriptors as NULL.
*/
if (regs->desc[0] != 0x01) {
for (int i = 0; i < 4; i++)
regs->regv[i] = 0;
return;
}
/*
* The most significant bit (MSB) of each register must be clear.
* If a register is invalid, replace its descriptors with NULL.
*/
for (int i = 0; i < 4; i++) {
if (regs->reg[i].invalid)
regs->regv[i] = 0;
}
}
/**
* for_each_leaf_0x2_entry() - Iterator for parsed leaf 0x2 descriptors
* @regs: Leaf 0x2 register output, returned by cpuid_get_leaf_0x2_regs()
* @__ptr: u8 pointer, for macro internal use only
* @entry: Pointer to parsed descriptor information at each iteration
*
* Loop over the 1-byte descriptors in the passed leaf 0x2 output registers
* @regs. Provide the parsed information for each descriptor through @entry.
*
* To handle cache-specific descriptors, switch on @entry->c_type. For TLB
* descriptors, switch on @entry->t_type.
*
* Example usage for cache descriptors::
*
* const struct leaf_0x2_table *entry;
* union leaf_0x2_regs regs;
* u8 *ptr;
*
* cpuid_get_leaf_0x2_regs(®s);
* for_each_leaf_0x2_entry(regs, ptr, entry) {
* switch (entry->c_type) {
* ...
* }
* }
*/
#define for_each_leaf_0x2_entry(regs, __ptr, entry) \
for (__ptr = &(regs).desc[1]; \
__ptr < &(regs).desc[16] && (entry = &cpuid_0x2_table[*__ptr]); \
__ptr++)
#endif /* _ASM_X86_CPUID_LEAF_0x2_API_H */
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