cachepc-linux

Fork of AMDESE/linux with modifications for CachePC side-channel attack
git clone https://git.sinitax.com/sinitax/cachepc-linux
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copy-paste.h (1372B)

      1/* SPDX-License-Identifier: GPL-2.0-or-later */
      2
      3/* From asm-compat.h */
      4#define __stringify_in_c(...)	#__VA_ARGS__
      5#define stringify_in_c(...)	__stringify_in_c(__VA_ARGS__) " "
      6
      7/*
      8 * Macros taken from arch/powerpc/include/asm/ppc-opcode.h and other
      9 * header files.
     10 */
     11#define ___PPC_RA(a)    (((a) & 0x1f) << 16)
     12#define ___PPC_RB(b)    (((b) & 0x1f) << 11)
     13
     14#define PPC_INST_COPY                   0x7c20060c
     15#define PPC_INST_PASTE                  0x7c20070d
     16
     17#define PPC_COPY(a, b)          stringify_in_c(.long PPC_INST_COPY | \
     18						___PPC_RA(a) | ___PPC_RB(b))
     19#define PPC_PASTE(a, b)         stringify_in_c(.long PPC_INST_PASTE | \
     20						___PPC_RA(a) | ___PPC_RB(b))
     21#define CR0_SHIFT	28
     22#define CR0_MASK	0xF
     23/*
     24 * Copy/paste instructions:
     25 *
     26 *	copy RA,RB
     27 *		Copy contents of address (RA) + effective_address(RB)
     28 *		to internal copy-buffer.
     29 *
     30 *	paste RA,RB
     31 *		Paste contents of internal copy-buffer to the address
     32 *		(RA) + effective_address(RB)
     33 */
     34static inline int vas_copy(void *crb, int offset)
     35{
     36	asm volatile(PPC_COPY(%0, %1)";"
     37		:
     38		: "b" (offset), "b" (crb)
     39		: "memory");
     40
     41	return 0;
     42}
     43
     44static inline int vas_paste(void *paste_address, int offset)
     45{
     46	__u32 cr;
     47
     48	cr = 0;
     49	asm volatile(PPC_PASTE(%1, %2)";"
     50		"mfocrf %0, 0x80;"
     51		: "=r" (cr)
     52		: "b" (offset), "b" (paste_address)
     53		: "memory", "cr0");
     54
     55	return (cr >> CR0_SHIFT) & CR0_MASK;
     56}