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Add custom ISA/PCI/AGP clock facility, and fix PIT clock calculation oversight for CPU clocks ending in (but not equal to) 33 and 66 MHz

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This commit is contained in:
RichardG867
2021-03-14 19:41:52 -03:00
parent 84c40909c7
commit dfee1165ea
4 changed files with 137 additions and 60 deletions
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19
src/pit.c
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@@ -44,8 +44,8 @@ pit_t *pit, *pit2;
double cpuclock, PITCONSTD,
SYSCLK,
isa_timing,
bus_timing, pci_timing,
PCICLK;
bus_timing, pci_timing, agp_timing,
PCICLK, AGPCLK;
uint64_t PITCONST, ISACONST,
CGACONST,
@@ -961,17 +961,18 @@ pit_set_clock(int clock)
{
/* Set default CPU/crystal clock and xt_cpu_multi. */
if (cpu_s->cpu_type >= CPU_286) {
if (clock == 66666666)
cpuclock = 200000000.0 / 3.0;
else if (clock == 33333333)
cpuclock = 100000000.0 / 3.0;
int remainder = (clock % 100000000);
if (remainder == 66666666)
cpuclock = (double) (clock - remainder) + (200000000.0 / 3.0);
else if (remainder == 33333333)
cpuclock = (double) (clock - remainder) + (100000000.0 / 3.0);
else
cpuclock = (double) clock;
PITCONSTD = (cpuclock / 1193182.0);
PITCONST = (uint64_t) (PITCONSTD * (double)(1ull << 32));
CGACONST = (uint64_t) ((cpuclock / (19687503.0/11.0)) * (double)(1ull << 32));
ISACONST = (uint64_t) ((cpuclock / 8000000.0) * (double)(1ull << 32));
ISACONST = (uint64_t) ((cpuclock / (double)cpu_isa_speed) * (double)(1ull << 32));
xt_cpu_multi = 1ULL;
} else {
cpuclock = 14318184.0;
@@ -1039,15 +1040,17 @@ pit_set_clock(int clock)
TIMER_USEC = (uint64_t)((cpuclock / 1000000.0) * (double)(1ull << 32));
isa_timing = (cpuclock / (double)8000000.0);
isa_timing = (cpuclock / (double)cpu_isa_speed);
if (cpu_64bitbus)
bus_timing = (cpuclock / ((double)cpu_busspeed / 2));
else
bus_timing = (cpuclock / (double)cpu_busspeed);
pci_timing = (cpuclock / (double)cpu_pci_speed);
agp_timing = (cpuclock / (double)cpu_agp_speed);
/* PCICLK in us for use with timer_on_auto(). */
PCICLK = pci_timing / (cpuclock / 1000000.0);
AGPCLK = agp_timing / (cpuclock / 1000000.0);
if (cpu_busspeed >= 30000000)
SYSCLK = bus_timing * 4.0;