22934e123c
This is a work in progress port to the mntreform2 laptop. Working so far: - mmu (same as raspberry pi 3b+) - arm generic timer - gicv3 - uart1 - enet With access to the uart, one can netboot this kernel in u-boot using the following commands: > dhcp > bootm
93 lines
1.1 KiB
C
93 lines
1.1 KiB
C
#include "u.h"
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#include "../port/lib.h"
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#include "mem.h"
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#include "dat.h"
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#include "fns.h"
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#include "ureg.h"
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#include "sysreg.h"
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/* libc */
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extern ulong getfcr(void);
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extern void setfcr(ulong fcr);
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extern ulong getfsr(void);
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extern void setfsr(ulong fsr);
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void
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fpuinit(void)
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{
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fpoff();
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}
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void
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fpon(void)
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{
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syswr(CPACR_EL1, 3<<20);
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}
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void
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fpoff(void)
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{
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syswr(CPACR_EL1, 0<<20);
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}
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void
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fpinit(void)
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{
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fpon();
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setfcr(0);
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setfsr(0);
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}
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void
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fpclear(void)
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{
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fpoff();
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}
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void
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fpsave(FPsave *p)
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{
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p->control = getfcr();
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p->status = getfsr();
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fpsaveregs(p->regs);
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fpoff();
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}
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void
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fprestore(FPsave *p)
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{
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fpon();
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setfcr(p->control);
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setfsr(p->status);
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fploadregs(p->regs);
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}
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void
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mathtrap(Ureg*)
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{
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int s;
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if((up->fpstate & FPillegal) != 0){
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postnote(up, 1, "sys: floating point in note handler", NDebug);
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return;
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}
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switch(up->fpstate){
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case FPinit:
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s = splhi();
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fpinit();
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up->fpstate = FPactive;
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splx(s);
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break;
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case FPinactive:
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s = splhi();
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fprestore(up->fpsave);
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up->fpstate = FPactive;
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splx(s);
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break;
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case FPactive:
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postnote(up, 1, "sys: floating point error", NDebug);
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break;
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}
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}
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