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powerpc: Use a datatype for instructions

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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
This commit is contained in:
Jordan Niethe
2020-05-06 13:40:31 +10:00
committed by Michael Ellerman
parent 217862d9b9
commit 94afd069d9
26 changed files with 237 additions and 214 deletions
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9
arch/powerpc/kernel/align.c
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@@ -105,7 +105,7 @@ static struct aligninfo spe_aligninfo[32] = {
* so we don't need the address swizzling.
*/
static int emulate_spe(struct pt_regs *regs, unsigned int reg,
unsigned int instr)
struct ppc_inst ppc_instr)
{
int ret;
union {
@@ -116,8 +116,9 @@ static int emulate_spe(struct pt_regs *regs, unsigned int reg,
} data, temp;
unsigned char __user *p, *addr;
unsigned long *evr = &current->thread.evr[reg];
unsigned int nb, flags;
unsigned int nb, flags, instr;
instr = ppc_inst_val(ppc_instr);
instr = (instr >> 1) & 0x1f;
/* DAR has the operand effective address */
@@ -294,7 +295,7 @@ static int emulate_spe(struct pt_regs *regs, unsigned int reg,
int fix_alignment(struct pt_regs *regs)
{
unsigned int instr;
struct ppc_inst instr;
struct instruction_op op;
int r, type;
@@ -304,7 +305,7 @@ int fix_alignment(struct pt_regs *regs)
*/
CHECK_FULL_REGS(regs);
if (unlikely(__get_user(instr, (unsigned int __user *)regs->nip)))
if (unlikely(__get_user(instr.val, (unsigned int __user *)regs->nip)))
return -EFAULT;
if ((regs->msr & MSR_LE) != (MSR_KERNEL & MSR_LE)) {
/* We don't handle PPC little-endian any more... */