minix/kernel/start.c
Ben Gras 9ba760e603 kernel: oxpcie serial card support.
ask to map in oxpcie i/o memory and support serial i/o for it in the
kernel. set oxpcie=<address> in boot monitor (retrieve address using
pci_debug=1 output). (no sanity checking is done on the address
currently.) disabled by default.

The change also contains some other minor cleanup (a new serial.h to set
register info common to UART and the OXPCIe card, in-kernel memory
mapping a little more structured and env_get() to get sysenv variables
without knowing about the params_buffer).
2010-05-19 10:00:02 +00:00

144 lines
4.1 KiB
C

/* First C file used by the kernel. */
#include "kernel.h"
#include "proc.h"
#include <stdlib.h>
#include <string.h>
#include "proto.h"
#ifdef CONFIG_WATCHDOG
#include "watchdog.h"
#endif
/*===========================================================================*
* cstart *
*===========================================================================*/
PUBLIC void cstart(
u16_t cs, /* kernel code segment */
u16_t ds, /* kernel data segment */
u16_t mds, /* monitor data segment */
u16_t parmoff, /* boot parameters offset */
u16_t parmsize /* boot parameters length */
)
{
/* Perform system initializations prior to calling main(). Most settings are
* determined with help of the environment strings passed by MINIX' loader.
*/
register char *value; /* value in key=value pair */
extern int etext, end;
int h;
/* Record where the kernel and the monitor are. */
kinfo.code_base = seg2phys(cs);
kinfo.code_size = (phys_bytes) &etext; /* size of code segment */
kinfo.data_base = seg2phys(ds);
kinfo.data_size = (phys_bytes) &end; /* size of data segment */
/* protection initialization */
prot_init();
/* Copy the boot parameters to the local buffer. */
arch_get_params(params_buffer, sizeof(params_buffer));
/* determine verbosity */
if ((value = env_get(VERBOSEBOOTVARNAME)))
verboseboot = atoi(value);
DEBUGEXTRA(("cstart\n"));
/* Record miscellaneous information for user-space servers. */
kinfo.nr_procs = NR_PROCS;
kinfo.nr_tasks = NR_TASKS;
strncpy(kinfo.release, OS_RELEASE, sizeof(kinfo.release));
kinfo.release[sizeof(kinfo.release)-1] = '\0';
strncpy(kinfo.version, OS_VERSION, sizeof(kinfo.version));
kinfo.version[sizeof(kinfo.version)-1] = '\0';
kinfo.proc_addr = (vir_bytes) proc;
/* Load average data initialization. */
kloadinfo.proc_last_slot = 0;
for(h = 0; h < _LOAD_HISTORY; h++)
kloadinfo.proc_load_history[h] = 0;
/* Processor? Decide if mode is protected for older machines. */
machine.processor=atoi(env_get("processor"));
/* XT, AT or MCA bus? */
value = env_get("bus");
if (value == NULL || strcmp(value, "at") == 0) {
machine.pc_at = TRUE; /* PC-AT compatible hardware */
} else if (strcmp(value, "mca") == 0) {
machine.pc_at = machine.ps_mca = TRUE; /* PS/2 with micro channel */
}
/* Type of VDU: */
value = env_get("video"); /* EGA or VGA video unit */
if (strcmp(value, "ega") == 0) machine.vdu_ega = TRUE;
if (strcmp(value, "vga") == 0) machine.vdu_vga = machine.vdu_ega = TRUE;
/* Get clock tick frequency. */
value = env_get("hz");
if(value)
system_hz = atoi(value);
if(!value || system_hz < 2 || system_hz > 50000) /* sanity check */
system_hz = DEFAULT_HZ;
value = env_get(SERVARNAME);
if(value && atoi(value) == 0)
do_serial_debug=1;
#ifdef CONFIG_APIC
value = env_get("no_apic");
if(value)
config_no_apic = atoi(value);
else
config_no_apic = 1;
#endif
#ifdef CONFIG_WATCHDOG
value = env_get("watchdog");
if (value)
watchdog_enabled = atoi(value);
#endif
/* Return to assembler code to switch to protected mode (if 286),
* reload selectors and call main().
*/
DEBUGEXTRA(("intr_init(%d, 0)\n", INTS_MINIX));
intr_init(INTS_MINIX, 0);
}
/*===========================================================================*
* get_value *
*===========================================================================*/
PRIVATE char *get_value(
const char *params, /* boot monitor parameters */
const char *name /* key to look up */
)
{
/* Get environment value - kernel version of getenv to avoid setting up the
* usual environment array.
*/
register const char *namep;
register char *envp;
for (envp = (char *) params; *envp != 0;) {
for (namep = name; *namep != 0 && *namep == *envp; namep++, envp++)
;
if (*namep == '\0' && *envp == '=') return(envp + 1);
while (*envp++ != 0)
;
}
return(NULL);
}
/*===========================================================================*
* env_get *
*===========================================================================*/
PUBLIC char *env_get(const char *name)
{
return get_value(params_buffer, name);
}