676 lines
15 KiB
C
676 lines
15 KiB
C
/* system dependent functions for use inside the whole kernel. */
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#include "kernel/kernel.h"
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#include <unistd.h>
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#include <ctype.h>
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#include <string.h>
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#include <machine/cmos.h>
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#include <machine/bios.h>
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#include <machine/cpu.h>
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#include <minix/portio.h>
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#include <minix/cpufeature.h>
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#include <assert.h>
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#include <signal.h>
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#include <machine/vm.h>
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#include <minix/u64.h>
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#include "archconst.h"
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#include "arch_proto.h"
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#include "serial.h"
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#include "oxpcie.h"
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#include <machine/multiboot.h>
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#include "glo.h"
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#ifdef USE_APIC
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#include "apic.h"
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#endif
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#ifdef USE_ACPI
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#include "acpi.h"
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#endif
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static int osfxsr_feature; /* FXSAVE/FXRSTOR instructions support (SSEx) */
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/* set MP and NE flags to handle FPU exceptions in native mode. */
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#define CR0_MP_NE 0x0022
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/* set CR4.OSFXSR[bit 9] if FXSR is supported. */
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#define CR4_OSFXSR (1L<<9)
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/* set OSXMMEXCPT[bit 10] if we provide #XM handler. */
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#define CR4_OSXMMEXCPT (1L<<10)
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void * k_stacks;
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static void ser_debug(int c);
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static void ser_dump_vfs(void);
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#ifdef CONFIG_SMP
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static void ser_dump_proc_cpu(void);
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#endif
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#if !CONFIG_OXPCIE
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static void ser_init(void);
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#endif
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void fpu_init(void)
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{
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unsigned short cw, sw;
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fninit();
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sw = fnstsw();
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fnstcw(&cw);
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if((sw & 0xff) == 0 &&
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(cw & 0x103f) == 0x3f) {
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/* We have some sort of FPU, but don't check exact model.
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* Set CR0_NE and CR0_MP to handle fpu exceptions
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* in native mode. */
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write_cr0(read_cr0() | CR0_MP_NE);
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get_cpulocal_var(fpu_presence) = 1;
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if(_cpufeature(_CPUF_I386_FXSR)) {
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u32_t cr4 = read_cr4() | CR4_OSFXSR; /* Enable FXSR. */
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/* OSXMMEXCPT if supported
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* FXSR feature can be available without SSE
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*/
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if(_cpufeature(_CPUF_I386_SSE))
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cr4 |= CR4_OSXMMEXCPT;
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write_cr4(cr4);
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osfxsr_feature = 1;
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} else {
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osfxsr_feature = 0;
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}
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} else {
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/* No FPU presents. */
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get_cpulocal_var(fpu_presence) = 0;
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osfxsr_feature = 0;
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return;
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}
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}
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void save_local_fpu(struct proc *pr, int retain)
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{
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char *state = pr->p_seg.fpu_state;
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/* Save process FPU context. If the 'retain' flag is set, keep the FPU
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* state as is. If the flag is not set, the state is undefined upon
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* return, and the caller is responsible for reloading a proper state.
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*/
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if(!is_fpu())
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return;
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assert(state);
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if(osfxsr_feature) {
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fxsave(state);
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} else {
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fnsave(state);
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if (retain)
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(void) frstor(state);
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}
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}
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void save_fpu(struct proc *pr)
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{
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#ifdef CONFIG_SMP
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if (cpuid != pr->p_cpu) {
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int stopped;
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/* remember if the process was already stopped */
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stopped = RTS_ISSET(pr, RTS_PROC_STOP);
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/* stop the remote process and force its context to be saved */
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smp_schedule_stop_proc_save_ctx(pr);
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/*
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* If the process wasn't stopped let the process run again. The
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* process is kept block by the fact that the kernel cannot run
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* on its cpu
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*/
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if (!stopped)
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RTS_UNSET(pr, RTS_PROC_STOP);
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return;
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}
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#endif
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if (get_cpulocal_var(fpu_owner) == pr) {
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disable_fpu_exception();
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save_local_fpu(pr, TRUE /*retain*/);
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}
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}
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/* reserve a chunk of memory for fpu state; every one has to
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* be FPUALIGN-aligned.
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*/
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static char fpu_state[NR_PROCS][FPU_XFP_SIZE] __aligned(FPUALIGN);
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void arch_proc_reset(struct proc *pr)
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{
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char *v = NULL;
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struct stackframe_s reg;
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assert(pr->p_nr < NR_PROCS);
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if(pr->p_nr >= 0) {
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v = fpu_state[pr->p_nr];
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/* verify alignment */
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assert(!((vir_bytes)v % FPUALIGN));
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/* initialize state */
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memset(v, 0, FPU_XFP_SIZE);
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}
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/* Clear process state. */
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memset(®, 0, sizeof(pr->p_reg));
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if(iskerneln(pr->p_nr))
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reg.psw = INIT_TASK_PSW;
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else
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reg.psw = INIT_PSW;
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pr->p_seg.fpu_state = v;
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/* Initialize the fundamentals that are (initially) the same for all
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* processes - the segment selectors it gets to use.
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*/
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pr->p_reg.cs = USER_CS_SELECTOR;
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pr->p_reg.gs =
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pr->p_reg.fs =
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pr->p_reg.ss =
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pr->p_reg.es =
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pr->p_reg.ds = USER_DS_SELECTOR;
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/* set full context and make sure it gets restored */
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arch_proc_setcontext(pr, ®, 0, KTS_FULLCONTEXT);
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}
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void arch_set_secondary_ipc_return(struct proc *p, u32_t val)
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{
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p->p_reg.bx = val;
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}
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int restore_fpu(struct proc *pr)
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{
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int failed;
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char *state = pr->p_seg.fpu_state;
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assert(state);
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if(!proc_used_fpu(pr)) {
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fninit();
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pr->p_misc_flags |= MF_FPU_INITIALIZED;
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} else {
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if(osfxsr_feature) {
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failed = fxrstor(state);
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} else {
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failed = frstor(state);
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}
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if (failed) return EINVAL;
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}
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return OK;
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}
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void cpu_identify(void)
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{
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u32_t eax, ebx, ecx, edx;
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unsigned cpu = cpuid;
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eax = 0;
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_cpuid(&eax, &ebx, &ecx, &edx);
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if (ebx == INTEL_CPUID_GEN_EBX && ecx == INTEL_CPUID_GEN_ECX &&
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edx == INTEL_CPUID_GEN_EDX) {
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cpu_info[cpu].vendor = CPU_VENDOR_INTEL;
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} else if (ebx == AMD_CPUID_GEN_EBX && ecx == AMD_CPUID_GEN_ECX &&
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edx == AMD_CPUID_GEN_EDX) {
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cpu_info[cpu].vendor = CPU_VENDOR_AMD;
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} else
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cpu_info[cpu].vendor = CPU_VENDOR_UNKNOWN;
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if (eax == 0)
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return;
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eax = 1;
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_cpuid(&eax, &ebx, &ecx, &edx);
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cpu_info[cpu].family = (eax >> 8) & 0xf;
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if (cpu_info[cpu].family == 0xf)
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cpu_info[cpu].family += (eax >> 20) & 0xff;
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cpu_info[cpu].model = (eax >> 4) & 0xf;
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if (cpu_info[cpu].model == 0xf || cpu_info[cpu].model == 0x6)
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cpu_info[cpu].model += ((eax >> 16) & 0xf) << 4 ;
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cpu_info[cpu].stepping = eax & 0xf;
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cpu_info[cpu].flags[0] = ecx;
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cpu_info[cpu].flags[1] = edx;
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}
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void arch_init(void)
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{
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k_stacks = (void*) &k_stacks_start;
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assert(!((vir_bytes) k_stacks % K_STACK_SIZE));
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#ifndef CONFIG_SMP
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/*
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* use stack 0 and cpu id 0 on a single processor machine, SMP
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* configuration does this in smp_init() for all cpus at once
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*/
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tss_init(0, get_k_stack_top(0));
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#endif
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#if !CONFIG_OXPCIE
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ser_init();
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#endif
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#ifdef USE_ACPI
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acpi_init();
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#endif
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#if defined(USE_APIC) && !defined(CONFIG_SMP)
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if (config_no_apic) {
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BOOT_VERBOSE(printf("APIC disabled, using legacy PIC\n"));
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}
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else if (!apic_single_cpu_init()) {
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BOOT_VERBOSE(printf("APIC not present, using legacy PIC\n"));
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}
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#endif
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/* Reserve some BIOS ranges */
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cut_memmap(&kinfo, BIOS_MEM_BEGIN, BIOS_MEM_END);
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cut_memmap(&kinfo, BASE_MEM_TOP, UPPER_MEM_END);
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}
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/*===========================================================================*
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* do_ser_debug *
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*===========================================================================*/
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void do_ser_debug()
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{
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u8_t c, lsr;
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#if CONFIG_OXPCIE
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{
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int oxin;
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if((oxin = oxpcie_in()) >= 0)
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ser_debug(oxin);
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}
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#endif
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lsr= inb(COM1_LSR);
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if (!(lsr & LSR_DR))
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return;
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c = inb(COM1_RBR);
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ser_debug(c);
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}
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static void ser_dump_queue_cpu(unsigned cpu)
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{
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int q;
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struct proc ** rdy_head;
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rdy_head = get_cpu_var(cpu, run_q_head);
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for(q = 0; q < NR_SCHED_QUEUES; q++) {
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struct proc *p;
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if(rdy_head[q]) {
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printf("%2d: ", q);
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for(p = rdy_head[q]; p; p = p->p_nextready) {
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printf("%s / %d ", p->p_name, p->p_endpoint);
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}
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printf("\n");
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}
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}
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}
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static void ser_dump_queues(void)
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{
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#ifdef CONFIG_SMP
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unsigned cpu;
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printf("--- run queues ---\n");
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for (cpu = 0; cpu < ncpus; cpu++) {
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printf("CPU %d :\n", cpu);
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ser_dump_queue_cpu(cpu);
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}
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#else
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ser_dump_queue_cpu(0);
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#endif
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}
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#ifdef CONFIG_SMP
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static void dump_bkl_usage(void)
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{
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unsigned cpu;
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printf("--- BKL usage ---\n");
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for (cpu = 0; cpu < ncpus; cpu++) {
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printf("cpu %3d kernel ticks 0x%x%08x bkl ticks 0x%x%08x succ %d tries %d\n", cpu,
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ex64hi(kernel_ticks[cpu]),
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ex64lo(kernel_ticks[cpu]),
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ex64hi(bkl_ticks[cpu]),
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ex64lo(bkl_ticks[cpu]),
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bkl_succ[cpu], bkl_tries[cpu]);
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}
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}
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static void reset_bkl_usage(void)
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{
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memset(kernel_ticks, 0, sizeof(kernel_ticks));
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memset(bkl_ticks, 0, sizeof(bkl_ticks));
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memset(bkl_tries, 0, sizeof(bkl_tries));
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memset(bkl_succ, 0, sizeof(bkl_succ));
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}
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#endif
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static void ser_debug(const int c)
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{
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serial_debug_active = 1;
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switch(c)
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{
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case 'Q':
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minix_shutdown(NULL);
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NOT_REACHABLE;
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#ifdef CONFIG_SMP
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case 'B':
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dump_bkl_usage();
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break;
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case 'b':
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reset_bkl_usage();
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break;
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#endif
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case '1':
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ser_dump_proc();
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break;
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case '2':
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ser_dump_queues();
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break;
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#ifdef CONFIG_SMP
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case '4':
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ser_dump_proc_cpu();
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break;
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#endif
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case '5':
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ser_dump_vfs();
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break;
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#if DEBUG_TRACE
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#define TOGGLECASE(ch, flag) \
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case ch: { \
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if(verboseflags & flag) { \
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verboseflags &= ~flag; \
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printf("%s disabled\n", #flag); \
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} else { \
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verboseflags |= flag; \
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printf("%s enabled\n", #flag); \
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} \
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break; \
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}
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TOGGLECASE('8', VF_SCHEDULING)
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TOGGLECASE('9', VF_PICKPROC)
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#endif
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#ifdef USE_APIC
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case 'I':
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dump_apic_irq_state();
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break;
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#endif
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}
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serial_debug_active = 0;
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}
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#if DEBUG_SERIAL
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static void ser_dump_vfs()
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{
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/* Notify VFS it has to generate stack traces. Kernel can't do that as
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* it's not aware of user space threads.
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*/
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mini_notify(proc_addr(KERNEL), VFS_PROC_NR);
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}
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#ifdef CONFIG_SMP
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static void ser_dump_proc_cpu(void)
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{
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struct proc *pp;
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unsigned cpu;
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for (cpu = 0; cpu < ncpus; cpu++) {
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printf("CPU %d processes : \n", cpu);
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for (pp= BEG_USER_ADDR; pp < END_PROC_ADDR; pp++) {
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if (isemptyp(pp) || pp->p_cpu != cpu)
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continue;
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print_proc(pp);
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}
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}
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}
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#endif
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#endif /* DEBUG_SERIAL */
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#if SPROFILE
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int arch_init_profile_clock(const u32_t freq)
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{
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int r;
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/* Set CMOS timer frequency. */
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outb(RTC_INDEX, RTC_REG_A);
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outb(RTC_IO, RTC_A_DV_OK | freq);
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/* Enable CMOS timer interrupts. */
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outb(RTC_INDEX, RTC_REG_B);
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r = inb(RTC_IO);
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outb(RTC_INDEX, RTC_REG_B);
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outb(RTC_IO, r | RTC_B_PIE);
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/* Mandatory read of CMOS register to enable timer interrupts. */
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outb(RTC_INDEX, RTC_REG_C);
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inb(RTC_IO);
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return CMOS_CLOCK_IRQ;
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}
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void arch_stop_profile_clock(void)
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{
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int r;
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/* Disable CMOS timer interrupts. */
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outb(RTC_INDEX, RTC_REG_B);
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r = inb(RTC_IO);
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outb(RTC_INDEX, RTC_REG_B);
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outb(RTC_IO, r & ~RTC_B_PIE);
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}
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void arch_ack_profile_clock(void)
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{
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/* Mandatory read of CMOS register to re-enable timer interrupts. */
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outb(RTC_INDEX, RTC_REG_C);
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inb(RTC_IO);
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}
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#endif
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void arch_do_syscall(struct proc *proc)
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{
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/* do_ipc assumes that it's running because of the current process */
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assert(proc == get_cpulocal_var(proc_ptr));
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/* Make the system call, for real this time. */
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assert(proc->p_misc_flags & MF_SC_DEFER);
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proc->p_reg.retreg =
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do_ipc(proc->p_defer.r1, proc->p_defer.r2, proc->p_defer.r3);
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}
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struct proc * arch_finish_switch_to_user(void)
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{
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char * stk;
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struct proc * p;
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#ifdef CONFIG_SMP
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stk = (char *)tss[cpuid].sp0;
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#else
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stk = (char *)tss[0].sp0;
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#endif
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/* set pointer to the process to run on the stack */
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p = get_cpulocal_var(proc_ptr);
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*((reg_t *)stk) = (reg_t) p;
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/* make sure IF is on in FLAGS so that interrupts won't be disabled
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* once p's context is restored.
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*/
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p->p_reg.psw |= IF_MASK;
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/* Set TRACEBIT state properly. */
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if(p->p_misc_flags & MF_STEP)
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p->p_reg.psw |= TRACEBIT;
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else
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p->p_reg.psw &= ~TRACEBIT;
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return p;
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}
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void arch_proc_setcontext(struct proc *p, struct stackframe_s *state,
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int isuser, int trap_style)
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{
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if(isuser) {
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/* Restore user bits of psw from sc, maintain system bits
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* from proc.
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*/
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state->psw = (state->psw & X86_FLAGS_USER) |
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(p->p_reg.psw & ~X86_FLAGS_USER);
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}
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/* someone wants to totally re-initialize process state */
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assert(sizeof(p->p_reg) == sizeof(*state));
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memcpy(&p->p_reg, state, sizeof(*state));
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/* further code is instructed to not touch the context
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* any more
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*/
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p->p_misc_flags |= MF_CONTEXT_SET;
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/* on x86 this requires returning using iret (KTS_INT)
|
|
* so that the full context is restored instead of relying on
|
|
* the userspace doing it (as it would do on SYSEXIT).
|
|
* as ESP and EIP are also reset, userspace won't try to
|
|
* restore bogus context after returning.
|
|
*
|
|
* if the process is not blocked, or the kernel will ignore
|
|
* our trap style, we needn't panic but things will probably
|
|
* not go well for the process (restored context will be ignored)
|
|
* and the situation should be debugged.
|
|
*/
|
|
if(!(p->p_rts_flags)) {
|
|
printf("WARNINIG: setting full context of runnable process\n");
|
|
print_proc(p);
|
|
util_stacktrace();
|
|
}
|
|
if(p->p_seg.p_kern_trap_style == KTS_NONE)
|
|
printf("WARNINIG: setting full context of out-of-kernel process\n");
|
|
p->p_seg.p_kern_trap_style = trap_style;
|
|
}
|
|
|
|
void restore_user_context(struct proc *p)
|
|
{
|
|
int trap_style = p->p_seg.p_kern_trap_style;
|
|
#if 0
|
|
#define TYPES 10
|
|
static int restores[TYPES], n = 0;
|
|
|
|
if(trap_style >= 0 && trap_style < TYPES)
|
|
restores[trap_style]++;
|
|
|
|
if(!(n++ % 500000)) {
|
|
int t;
|
|
for(t = 0; t < TYPES; t++)
|
|
if(restores[t])
|
|
printf("%d: %d ", t, restores[t]);
|
|
printf("\n");
|
|
}
|
|
#endif
|
|
|
|
p->p_seg.p_kern_trap_style = KTS_NONE;
|
|
|
|
if(trap_style == KTS_SYSENTER) {
|
|
restore_user_context_sysenter(p);
|
|
NOT_REACHABLE;
|
|
}
|
|
|
|
if(trap_style == KTS_SYSCALL) {
|
|
restore_user_context_syscall(p);
|
|
NOT_REACHABLE;
|
|
}
|
|
|
|
switch(trap_style) {
|
|
case KTS_NONE:
|
|
panic("no entry trap style known");
|
|
case KTS_INT_HARD:
|
|
case KTS_INT_UM:
|
|
case KTS_FULLCONTEXT:
|
|
case KTS_INT_ORIG:
|
|
restore_user_context_int(p);
|
|
NOT_REACHABLE;
|
|
default:
|
|
panic("unknown trap style recorded");
|
|
NOT_REACHABLE;
|
|
}
|
|
|
|
NOT_REACHABLE;
|
|
}
|
|
|
|
void fpu_sigcontext(struct proc *pr, struct sigframe *fr, struct sigcontext *sc)
|
|
{
|
|
int fp_error;
|
|
|
|
if (osfxsr_feature) {
|
|
fp_error = sc->sc_fpu_state.xfp_regs.fp_status &
|
|
~sc->sc_fpu_state.xfp_regs.fp_control;
|
|
} else {
|
|
fp_error = sc->sc_fpu_state.fpu_regs.fp_status &
|
|
~sc->sc_fpu_state.fpu_regs.fp_control;
|
|
}
|
|
|
|
if (fp_error & 0x001) { /* Invalid op */
|
|
/*
|
|
* swd & 0x240 == 0x040: Stack Underflow
|
|
* swd & 0x240 == 0x240: Stack Overflow
|
|
* User must clear the SF bit (0x40) if set
|
|
*/
|
|
fr->sf_code = FPE_FLTINV;
|
|
} else if (fp_error & 0x004) {
|
|
fr->sf_code = FPE_FLTDIV; /* Divide by Zero */
|
|
} else if (fp_error & 0x008) {
|
|
fr->sf_code = FPE_FLTOVF; /* Overflow */
|
|
} else if (fp_error & 0x012) {
|
|
fr->sf_code = FPE_FLTUND; /* Denormal, Underflow */
|
|
} else if (fp_error & 0x020) {
|
|
fr->sf_code = FPE_FLTRES; /* Precision */
|
|
} else {
|
|
fr->sf_code = 0; /* XXX - probably should be used for FPE_INTOVF or
|
|
* FPE_INTDIV */
|
|
}
|
|
}
|
|
|
|
reg_t arch_get_sp(struct proc *p) { return p->p_reg.sp; }
|
|
|
|
#if !CONFIG_OXPCIE
|
|
static void ser_init(void)
|
|
{
|
|
unsigned char lcr;
|
|
unsigned divisor;
|
|
|
|
/* keep BIOS settings if cttybaud is not set */
|
|
if (kinfo.serial_debug_baud <= 0) return;
|
|
|
|
/* set DLAB to make baud accessible */
|
|
lcr = LCR_8BIT | LCR_1STOP | LCR_NPAR;
|
|
outb(COM1_LCR, lcr | LCR_DLAB);
|
|
|
|
/* set baud rate */
|
|
divisor = UART_BASE_FREQ / kinfo.serial_debug_baud;
|
|
if (divisor < 1) divisor = 1;
|
|
if (divisor > 65535) divisor = 65535;
|
|
|
|
outb(COM1_DLL, divisor & 0xff);
|
|
outb(COM1_DLM, (divisor >> 8) & 0xff);
|
|
|
|
/* clear DLAB */
|
|
outb(COM1_LCR, lcr);
|
|
}
|
|
#endif
|