From ba862f2f6529d1e7ce8951d02d43ab7894db80e6 Mon Sep 17 00:00:00 2001 From: pumnflqv2 Date: Sun, 26 Jun 2022 22:18:13 +0800 Subject: [PATCH] ADD file via upload --- kernel/blk_drv/hd.c | 351 ++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 351 insertions(+) create mode 100644 kernel/blk_drv/hd.c diff --git a/kernel/blk_drv/hd.c b/kernel/blk_drv/hd.c new file mode 100644 index 0000000..c0e908f --- /dev/null +++ b/kernel/blk_drv/hd.c @@ -0,0 +1,351 @@ +/* + * linux/kernel/hd.c + * + * (C) 1991 Linus Torvalds + */ + +/* + * This is the low-level hd interrupt support. It traverses the + * request-list, using interrupts to jump between functions. As + * all the functions are called within interrupts, we may not + * sleep. Special care is recommended. + * + * modified by Drew Eckhardt to check nr of hd's from the CMOS. + */ + +#include +#include +#include +#include +#include +#include +#include +#include + +#define MAJOR_NR 3 +#include "blk.h" + +#define CMOS_READ(addr) ({ \ +outb_p(0x80|addr,0x70); \ +inb_p(0x71); \ +}) + +/* Max read/write errors/sector */ +#define MAX_ERRORS 7 +#define MAX_HD 2 + +static void recal_intr(void); + +static int recalibrate = 0; /* 1, wen */ +static int reset = 0; + +/* + * This struct defines the HD's and their types. + */ +struct hd_i_struct { + int head,sect,cyl,wpcom,lzone,ctl; + }; +#ifdef HD_TYPE +struct hd_i_struct hd_info[] = { HD_TYPE }; +#define NR_HD ((sizeof (hd_info))/(sizeof (struct hd_i_struct))) +#else +struct hd_i_struct hd_info[] = { {0,0,0,0,0,0},{0,0,0,0,0,0} }; +static int NR_HD = 0; +#endif + +static struct hd_struct { + long start_sect; + long nr_sects; +} hd[5*MAX_HD]={{0,0},}; + +#define port_read(port,buf,nr) \ +__asm__("cld;rep;insw"::"d" (port),"D" (buf),"c" (nr)) + +#define port_write(port,buf,nr) \ +__asm__("cld;rep;outsw"::"d" (port),"S" (buf),"c" (nr)) + +extern void hd_interrupt(void); +extern void rd_load(void); + +/* This may be used only once, enforced by 'static int callable' */ +int sys_setup(void * BIOS) +{ + static int callable = 1; + int i,drive; + unsigned char cmos_disks; + struct partition *p; + struct buffer_head * bh; + + if (!callable) + return -1; + callable = 0; +#ifndef HD_TYPE + for (drive=0 ; drive<2 ; drive++) { + hd_info[drive].cyl = *(unsigned short *) BIOS; + hd_info[drive].head = *(unsigned char *) (2+BIOS); + hd_info[drive].wpcom = *(unsigned short *) (5+BIOS); + hd_info[drive].ctl = *(unsigned char *) (8+BIOS); + hd_info[drive].lzone = *(unsigned short *) (12+BIOS); + hd_info[drive].sect = *(unsigned char *) (14+BIOS); + BIOS += 16; + } + if (hd_info[1].cyl) + NR_HD=2; + else + NR_HD=1; +#endif + for (i=0 ; i are the primary drives in the system, and + the ones reflected as drive 1 or 2. + + The first drive is stored in the high nibble of CMOS + byte 0x12, the second in the low nibble. This will be + either a 4 bit drive type or 0xf indicating use byte 0x19 + for an 8 bit type, drive 1, 0x1a for drive 2 in CMOS. + + Needless to say, a non-zero value means we have + an AT controller hard disk for that drive. + + + */ + + if ((cmos_disks = CMOS_READ(0x12)) & 0xf0) + if (cmos_disks & 0x0f) + NR_HD = 2; + else + NR_HD = 1; + else + NR_HD = 0; + for (i = NR_HD ; i < 2 ; i++) { + hd[i*5].start_sect = 0; + hd[i*5].nr_sects = 0; + } + for (drive=0 ; driveb_data[510] != 0x55 || (unsigned char) + bh->b_data[511] != 0xAA) { + printk("Bad partition table on drive %d\n\r",drive); + panic(""); + } + p = 0x1BE + (void *)bh->b_data; + for (i=1;i<5;i++,p++) { + hd[i+5*drive].start_sect = p->start_sect; + hd[i+5*drive].nr_sects = p->nr_sects; + } + brelse(bh); + } + if (NR_HD) + printk("Partition table%s ok.\n\r",(NR_HD>1)?"s":""); + rd_load(); + mount_root(); + return (0); +} + +static int controller_ready(void) +{ + /* int retries=10000; */ + int retries=100000; + + /* while (--retries && (inb_p(HD_STATUS)&0xc0)!=0x40); */ + while (--retries && (inb_p(HD_STATUS)&0x80)); + return (retries); +} + +static int win_result(void) +{ + int i=inb_p(HD_STATUS); + + if ((i & (BUSY_STAT | READY_STAT | WRERR_STAT | SEEK_STAT | ERR_STAT)) + == (READY_STAT | SEEK_STAT)) + return(0); /* ok */ + if (i&1) i=inb(HD_ERROR); + return (1); +} + +static void hd_out(unsigned int drive,unsigned int nsect,unsigned int sect, + unsigned int head,unsigned int cyl,unsigned int cmd, + void (*intr_addr)(void)) +{ + register int port asm("dx"); + + if (drive>1 || head>15) + panic("Trying to write bad sector"); + if (!controller_ready()) + panic("HD controller not ready"); + do_hd = intr_addr; + outb_p(hd_info[drive].ctl,HD_CMD); + port=HD_DATA; + outb_p(hd_info[drive].wpcom>>2,++port); + outb_p(nsect,++port); + outb_p(sect,++port); + outb_p(cyl,++port); + outb_p(cyl>>8,++port); + outb_p(0xA0|(drive<<4)|head,++port); + outb(cmd,++port); +} + +static int drive_busy(void) +{ + unsigned int i; + + for (i = 0; i < 10000; i++) + if (READY_STAT == (inb_p(HD_STATUS) & (BUSY_STAT|READY_STAT))) + break; + i = inb(HD_STATUS); + i &= BUSY_STAT | READY_STAT | SEEK_STAT; + if (i == READY_STAT | SEEK_STAT) + return(0); + printk("HD controller times out\n\r"); + return(1); +} + +static void reset_controller(void) +{ + int i; + + outb(4,HD_CMD); + for(i = 0; i < 100; i++) nop(); + outb(hd_info[0].ctl & 0x0f ,HD_CMD); + if (drive_busy()) + printk("HD-controller still busy\n\r"); + if ((i = inb(HD_ERROR)) != 1) + printk("HD-controller reset failed: %02x\n\r",i); +} + +static void reset_hd(int nr) +{ + reset_controller(); + hd_out(nr,hd_info[nr].sect,hd_info[nr].sect,hd_info[nr].head-1, + hd_info[nr].cyl,WIN_SPECIFY,&recal_intr); +} + +void unexpected_hd_interrupt(void) +{ + printk("Unexpected HD interrupt\n\r"); +} + +static void bad_rw_intr(void) +{ + if (++CURRENT->errors >= MAX_ERRORS) + end_request(0); + if (CURRENT->errors > MAX_ERRORS/2) + reset = 1; +} + +static void read_intr(void) +{ + if (win_result()) { + bad_rw_intr(); + do_hd_request(); + return; + } + port_read(HD_DATA,CURRENT->buffer,256); + CURRENT->errors = 0; + CURRENT->buffer += 512; + CURRENT->sector++; + if (--CURRENT->nr_sectors) { + do_hd = &read_intr; + return; + } + end_request(1); + do_hd_request(); +} + +static void write_intr(void) +{ + if (win_result()) { + bad_rw_intr(); + do_hd_request(); + return; + } + if (--CURRENT->nr_sectors) { + CURRENT->sector++; + CURRENT->buffer += 512; + do_hd = &write_intr; + port_write(HD_DATA,CURRENT->buffer,256); + return; + } + end_request(1); + do_hd_request(); +} + +static void recal_intr(void) +{ + if (win_result()) + bad_rw_intr(); + do_hd_request(); +} + +void do_hd_request(void) +{ + int i,r; + unsigned int block,dev; + unsigned int sec,head,cyl; + unsigned int nsect; + + INIT_REQUEST; + dev = MINOR(CURRENT->dev); + block = CURRENT->sector; + if (dev >= 5*NR_HD || block+2 > hd[dev].nr_sects) { + end_request(0); + goto repeat; + } + block += hd[dev].start_sect; + dev /= 5; + __asm__("divl %4":"=a" (block),"=d" (sec):"0" (block),"1" (0), + "r" (hd_info[dev].sect)); + __asm__("divl %4":"=a" (cyl),"=d" (head):"0" (block),"1" (0), + "r" (hd_info[dev].head)); + sec++; + nsect = CURRENT->nr_sectors; + if (reset) { + reset = 0; + recalibrate = 1; + reset_hd(CURRENT_DEV); + return; + } + if (recalibrate) { + recalibrate = 0; + hd_out(dev,hd_info[CURRENT_DEV].sect,0,0,0, + WIN_RESTORE,&recal_intr); + return; + } + if (CURRENT->cmd == WRITE) { + hd_out(dev,nsect,sec,head,cyl,WIN_WRITE,&write_intr); + for(i=0 ; i<3000 && !(r=inb_p(HD_STATUS)&DRQ_STAT) ; i++) + /* nothing */ ; + if (!r) { + bad_rw_intr(); + goto repeat; + } + port_write(HD_DATA,CURRENT->buffer,256); + } else if (CURRENT->cmd == READ) { + hd_out(dev,nsect,sec,head,cyl,WIN_READ,&read_intr); + } else + panic("unknown hd-command"); +} + +void hd_init(void) +{ + blk_dev[MAJOR_NR].request_fn = DEVICE_REQUEST; + set_intr_gate(0x2E,&hd_interrupt); + outb_p(inb_p(0x21)&0xfb,0x21); + outb(inb_p(0xA1)&0xbf,0xA1); +}