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Reworked VC4 relocations and some of the instruction encoding to be actually correct. Now generating what could be real code!

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--HG--
branch : dtrg-videocore
This commit is contained in:
David Given
2013-05-21 23:17:30 +01:00
parent 1312fe298b
commit 5e9102955c
4 changed files with 187 additions and 53 deletions
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151
util/led/relocate.c
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@@ -8,6 +8,7 @@ static char rcsid[] = "$Id$";
#include <stdlib.h>
#include <stdio.h>
#include <stdint.h>
#include <assert.h>
#include "out.h"
#include "const.h"
@@ -44,6 +45,65 @@ static long read4(char* addr, int type)
return ((long)word1 << (2 * WIDTH)) + word0;
}
/* VideoCore 4 fixups are complex as we need to patch the instruction in
* one of several different ways (depending on what the instruction is).
*/
static long get_vc4_valu(char* addr)
{
uint16_t opcode = read2(addr, 0);
if ((opcode & 0xff00) == 0xe700)
{
/* ld<w> rd, $+o: [1110 0111 ww 0 d:5] [11111 o:27]
* st<w> rd, $+o: [1110 0111 ww 1 d:5] [11111 o:27]
*/
int32_t value = read4(addr+2, 0);
value &= 0x07ffffff;
value = value<<5>>5;
return value;
}
if ((opcode & 0xf080) == 0x9000)
{
/* b<cc> $+o*2: [1001 cccc 0ooo oooo] [oooo oooo oooo oooo]
* Yes, big-endian (the first 16 bits is the MSB).
*/
uint32_t value = read4(addr, RELWR);
value &= 0x007fffff;
value = value<<9>>9;
value *= 2;
return value;
}
if ((opcode & 0xf080) == 0x9080)
{
/* bl $+o*2: [1001 oooo 1ooo oooo] [oooo oooo oooo oooo]
* Yes, big-endian (the first 16 bits is the MSB).
* (Note that o is split.)
*/
int32_t value = read4(addr, RELWR);
int32_t lov = value & 0x007fffff;
int32_t hiv = value & 0x0f000000;
value = lov | (hiv>>1);
value = value<<5>>5;
value *= 2;
return value;
}
if ((opcode & 0xffe0) == 0xe500)
{
/* lea: [1110 0101 000 d:5] [o:32] */
return read4(addr+2, 0);
}
assert(0 && "unrecognised VC4 instruction");
}
/*
* The bits in type indicate how many bytes the value occupies and what
* significance should be attributed to each byte.
@@ -65,21 +125,7 @@ getvalu(addr, type)
case RELOH2:
return read2(addr, type) << 16;
case RELOVC4:
{
long i = read4(addr, type);
if (i & 0x00800000)
{
/* Branch instruction. */
return (i<<9)>>9;
}
else
{
/* Branch-link instruction. */
long hi = (i<<4)>>28;
long lo = (i & 0x007fffff);
return lo | (hi<<23);
}
}
return get_vc4_valu(addr);
default:
fatal("bad relocation size");
}
@@ -123,6 +169,60 @@ static void write4(long valu, char* addr, int type)
}
}
/* VideoCore 4 fixups are complex as we need to patch the instruction in
* one of several different ways (depending on what the instruction is).
*/
static void put_vc4_valu(char* addr, long value)
{
uint16_t opcode = read2(addr, 0);
if ((opcode & 0xff00) == 0xe700)
{
/* ld<w> rd, o, (pc): [1110 0111 ww 0 d:5] [11111 o:27]
* st<w> rd, o, (pc): [1110 0111 ww 1 d:5] [11111 o:27]
*/
uint32_t v = read4(addr+2, 0);
v &= 0xf8000000;
v |= value & 0x07ffffff;
write4(v, addr+2, 0);
}
else if ((opcode & 0xf080) == 0x9000)
{
/* b<cc> dest: [1001 cccc 0ooo oooo] [oooo oooo oooo oooo]
* Yes, big-endian (the first 16 bits is the MSB).
*/
uint32_t v = read4(addr, RELWR);
v &= 0xff800000;
v |= (value/2) & 0x007fffff;
write4(v, addr, RELWR);
}
else if ((opcode & 0xf080) == 0x9080)
{
/* bl dest: [1001 oooo 1ooo oooo] [oooo oooo oooo oooo]
* Yes, big-endian (the first 16 bits is the MSB).
* (Note that o is split.)
*/
uint32_t v = read4(addr, RELWR);
uint32_t lovalue = (value/2) & 0x007fffff;
uint32_t hivalue = (value/2) & 0x07800000;
v &= 0xf0800000;
v |= lovalue | (hivalue<<1);
write4(v, addr, RELWR);
}
else if ((opcode & 0xffe0) == 0xe500)
{
/* lea: [1110 0101 000 d:5] [o:32] */
write4(value, addr+2, 0);
}
else
assert(0 && "unrecognised VC4 instruction");
}
/*
* The bits in type indicate how many bytes the value occupies and what
* significance should be attributed to each byte.
@@ -156,27 +256,8 @@ putvalu(valu, addr, type)
write2(valu>>16, addr, type);
break;
case RELOVC4:
{
long i = read4(addr, type);
if (i & 0x00800000)
{
/* Branch instruction. */
unsigned v = (valu/2) & 0x007fffff;
i &= ~0x007fffff;
i |= v;
}
else
{
/* Branch-link instruction. */
unsigned v = (valu/2) & 0x07ffffff;
unsigned hiv = v >> 23;
unsigned lov = v & 0x007fffff;
i &= ~0x0f7fffff;
i |= (lov>>16) | (hiv<<24);
}
write4(i, addr, type);
put_vc4_valu(addr, valu);
break;
}
default:
fatal("bad relocation size");
}