mirror of
https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git
synced 2024-08-23 17:30:02 +00:00
![Jordan Niethe](/assets/img/avatar_default.png)
Currently unsigned ints are used to represent instructions on powerpc. This has worked well as instructions have always been 4 byte words. However, ISA v3.1 introduces some changes to instructions that mean this scheme will no longer work as well. This change is Prefixed Instructions. A prefixed instruction is made up of a word prefix followed by a word suffix to make an 8 byte double word instruction. No matter the endianness of the system the prefix always comes first. Prefixed instructions are only planned for powerpc64. Introduce a ppc_inst type to represent both prefixed and word instructions on powerpc64 while keeping it possible to exclusively have word instructions on powerpc32. Signed-off-by: Jordan Niethe <jniethe5@gmail.com> [mpe: Fix compile error in emulate_spe()] Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20200506034050.24806-12-jniethe5@gmail.com
74 lines
1.6 KiB
C
74 lines
1.6 KiB
C
// SPDX-License-Identifier: GPL-2.0-only
|
|
/*
|
|
* ePAPR para-virtualization support.
|
|
*
|
|
* Copyright (C) 2012 Freescale Semiconductor, Inc.
|
|
*/
|
|
|
|
#include <linux/of.h>
|
|
#include <linux/of_fdt.h>
|
|
#include <asm/epapr_hcalls.h>
|
|
#include <asm/cacheflush.h>
|
|
#include <asm/code-patching.h>
|
|
#include <asm/machdep.h>
|
|
#include <asm/inst.h>
|
|
|
|
#if !defined(CONFIG_64BIT) || defined(CONFIG_PPC_BOOK3E_64)
|
|
extern void epapr_ev_idle(void);
|
|
extern u32 epapr_ev_idle_start[];
|
|
#endif
|
|
|
|
bool epapr_paravirt_enabled;
|
|
static bool __maybe_unused epapr_has_idle;
|
|
|
|
static int __init early_init_dt_scan_epapr(unsigned long node,
|
|
const char *uname,
|
|
int depth, void *data)
|
|
{
|
|
const u32 *insts;
|
|
int len;
|
|
int i;
|
|
|
|
insts = of_get_flat_dt_prop(node, "hcall-instructions", &len);
|
|
if (!insts)
|
|
return 0;
|
|
|
|
if (len % 4 || len > (4 * 4))
|
|
return -1;
|
|
|
|
for (i = 0; i < (len / 4); i++) {
|
|
struct ppc_inst inst = ppc_inst(be32_to_cpu(insts[i]));
|
|
patch_instruction((struct ppc_inst *)(epapr_hypercall_start + i), inst);
|
|
#if !defined(CONFIG_64BIT) || defined(CONFIG_PPC_BOOK3E_64)
|
|
patch_instruction((struct ppc_inst *)(epapr_ev_idle_start + i), inst);
|
|
#endif
|
|
}
|
|
|
|
#if !defined(CONFIG_64BIT) || defined(CONFIG_PPC_BOOK3E_64)
|
|
if (of_get_flat_dt_prop(node, "has-idle", NULL))
|
|
epapr_has_idle = true;
|
|
#endif
|
|
|
|
epapr_paravirt_enabled = true;
|
|
|
|
return 1;
|
|
}
|
|
|
|
int __init epapr_paravirt_early_init(void)
|
|
{
|
|
of_scan_flat_dt(early_init_dt_scan_epapr, NULL);
|
|
|
|
return 0;
|
|
}
|
|
|
|
static int __init epapr_idle_init(void)
|
|
{
|
|
#if !defined(CONFIG_64BIT) || defined(CONFIG_PPC_BOOK3E_64)
|
|
if (epapr_has_idle)
|
|
ppc_md.power_save = epapr_ev_idle;
|
|
#endif
|
|
|
|
return 0;
|
|
}
|
|
|
|
postcore_initcall(epapr_idle_init);
|