sdata.c

这是一个同样来自贝尔实验室的和UNIX有着渊源的操作系统, 其简洁的设计和实现易于我们学习和理解

#include "u.h"
#include "../port/lib.h"
#include "mem.h"
#include "dat.h"
#include "fns.h"
#include "io.h"
#include "ureg.h"
#include "../port/error.h"

#include "../port/sd.h"

#define	HOWMANY(x, y)	(((x)+((y)-1))/(y))
#define ROUNDUP(x, y)	(HOWMANY((x), (y))*(y))

extern SDifc sdataifc;

enum {
	DbgCONFIG	= 0x0001,	/* detected drive config info */
	DbgIDENTIFY	= 0x0002,	/* detected drive identify info */
	DbgSTATE	= 0x0004,	/* dump state on panic */
	DbgPROBE	= 0x0008,	/* trace device probing */
	DbgDEBUG	= 0x0080,	/* the current problem... */
	DbgINL		= 0x0100,	/* That Inil20+ message we hate */
	Dbg48BIT	= 0x0200,	/* 48-bit LBA */
	DbgBsy		= 0x0400,	/* interrupt but Bsy (shared IRQ) */
};
#define DEBUG		(DbgDEBUG|DbgSTATE)

enum {					/* I/O ports */
	Data		= 0,
	Error		= 1,		/* (read) */
	Features	= 1,		/* (write) */
	Count		= 2,		/* sector count<7-0>, sector count<15-8> */
	Ir		= 2,		/* interrupt reason (PACKET) */
	Sector		= 3,		/* sector number */
	Lbalo		= 3,		/* LBA<7-0>, LBA<31-24> */
	Cyllo		= 4,		/* cylinder low */
	Bytelo		= 4,		/* byte count low (PACKET) */
	Lbamid		= 4,		/* LBA<15-8>, LBA<39-32> */
	Cylhi		= 5,		/* cylinder high */
	Bytehi		= 5,		/* byte count hi (PACKET) */
	Lbahi		= 5,		/* LBA<23-16>, LBA<47-40> */
	Dh		= 6,		/* Device/Head, LBA<32-14> */
	Status		= 7,		/* (read) */
	Command		= 7,		/* (write) */

	As		= 2,		/* Alternate Status (read) */
	Dc		= 2,		/* Device Control (write) */
};

enum {					/* Error */
	Med		= 0x01,		/* Media error */
	Ili		= 0x01,		/* command set specific (PACKET) */
	Nm		= 0x02,		/* No Media */
	Eom		= 0x02,		/* command set specific (PACKET) */
	Abrt		= 0x04,		/* Aborted command */
	Mcr		= 0x08,		/* Media Change Request */
	Idnf		= 0x10,		/* no user-accessible address */
	Mc		= 0x20,		/* Media Change */
	Unc		= 0x40,		/* Uncorrectable data error */
	Wp		= 0x40,		/* Write Protect */
	Icrc		= 0x80,		/* Interface CRC error */
};

enum {					/* Features */
	Dma		= 0x01,		/* data transfer via DMA (PACKET) */
	Ovl		= 0x02,		/* command overlapped (PACKET) */
};

enum {					/* Interrupt Reason */
	Cd		= 0x01,		/* Command/Data */
	Io		= 0x02,		/* I/O direction */
	Rel		= 0x04,		/* Bus Release */
};

enum {					/* Device/Head */
	Dev0		= 0xA0,		/* Master */
	Dev1		= 0xB0,		/* Slave */
	Lba		= 0x40,		/* LBA mode */
};

enum {					/* Status, Alternate Status */
	Err		= 0x01,		/* Error */
	Chk		= 0x01,		/* Check error (PACKET) */
	Drq		= 0x08,		/* Data Request */
	Dsc		= 0x10,		/* Device Seek Complete */
	Serv		= 0x10,		/* Service */
	Df		= 0x20,		/* Device Fault */
	Dmrd		= 0x20,		/* DMA ready (PACKET) */
	Drdy		= 0x40,		/* Device Ready */
	Bsy		= 0x80,		/* Busy */
};

enum {					/* Command */
	Cnop		= 0x00,		/* NOP */
	Cdr		= 0x08,		/* Device Reset */
	Crs		= 0x20,		/* Read Sectors */
	Crs48		= 0x24,		/* Read Sectors Ext */
	Crd48		= 0x25,		/* Read w/ DMA Ext */
	Crdq48		= 0x26,		/* Read w/ DMA Queued Ext */
	Crsm48		= 0x29,		/* Read Multiple Ext */
	Cws		= 0x30,		/* Write Sectors */
	Cws48		= 0x34,		/* Write Sectors Ext */
	Cwd48		= 0x35,		/* Write w/ DMA Ext */
	Cwdq48		= 0x36,		/* Write w/ DMA Queued Ext */
	Cwsm48		= 0x39,		/* Write Multiple Ext */
	Cedd		= 0x90,		/* Execute Device Diagnostics */
	Cpkt		= 0xA0,		/* Packet */
	Cidpkt		= 0xA1,		/* Identify Packet Device */
	Crsm		= 0xC4,		/* Read Multiple */
	Cwsm		= 0xC5,		/* Write Multiple */
	Csm		= 0xC6,		/* Set Multiple */
	Crdq		= 0xC7,		/* Read DMA queued */
	Crd		= 0xC8,		/* Read DMA */
	Cwd		= 0xCA,		/* Write DMA */
	Cwdq		= 0xCC,		/* Write DMA queued */
	Cstandby	= 0xE2,		/* Standby */
	Cid		= 0xEC,		/* Identify Device */
	Csf		= 0xEF,		/* Set Features */
};

enum {					/* Device Control */
	Nien		= 0x02,		/* (not) Interrupt Enable */
	Srst		= 0x04,		/* Software Reset */
	Hob		= 0x80,		/* High Order Bit [sic] */
};

enum {					/* PCI Configuration Registers */
	Bmiba		= 0x20,		/* Bus Master Interface Base Address */
	Idetim		= 0x40,		/* IE Timing */
	Sidetim		= 0x44,		/* Slave IE Timing */
	Udmactl		= 0x48,		/* Ultra DMA/33 Control */
	Udmatim		= 0x4A,		/* Ultra DMA/33 Timing */
};

enum {					/* Bus Master IDE I/O Ports */
	Bmicx		= 0,		/* Command */
	Bmisx		= 2,		/* Status */
	Bmidtpx		= 4,		/* Descriptor Table Pointer */
};

enum {					/* Bmicx */
	Ssbm		= 0x01,		/* Start/Stop Bus Master */
	Rwcon		= 0x08,		/* Read/Write Control */
};

enum {					/* Bmisx */
	Bmidea		= 0x01,		/* Bus Master IDE Active */
	Idedmae		= 0x02,		/* IDE DMA Error  (R/WC) */
	Ideints		= 0x04,		/* IDE Interrupt Status (R/WC) */
	Dma0cap		= 0x20,		/* Drive 0 DMA Capable */
	Dma1cap		= 0x40,		/* Drive 0 DMA Capable */
};
enum {					/* Physical Region Descriptor */
	PrdEOT		= 0x80000000,	/* End of Transfer */
};

enum {					/* offsets into the identify info. */
	Iconfig		= 0,		/* general configuration */
	Ilcyl		= 1,		/* logical cylinders */
	Ilhead		= 3,		/* logical heads */
	Ilsec		= 6,		/* logical sectors per logical track */
	Iserial		= 10,		/* serial number */
	Ifirmware	= 23,		/* firmware revision */
	Imodel		= 27,		/* model number */
	Imaxrwm		= 47,		/* max. read/write multiple sectors */
	Icapabilities	= 49,		/* capabilities */
	Istandby	= 50,		/* device specific standby timer */
	Ipiomode	= 51,		/* PIO data transfer mode number */
	Ivalid		= 53,
	Iccyl		= 54,		/* cylinders if (valid&0x01) */
	Ichead		= 55,		/* heads if (valid&0x01) */
	Icsec		= 56,		/* sectors if (valid&0x01) */
	Iccap		= 57,		/* capacity if (valid&0x01) */
	Irwm		= 59,		/* read/write multiple */
	Ilba		= 60,		/* LBA size */
	Imwdma		= 63,		/* multiword DMA mode */
	Iapiomode	= 64,		/* advanced PIO modes supported */
	Iminmwdma	= 65,		/* min. multiword DMA cycle time */
	Irecmwdma	= 66,		/* rec. multiword DMA cycle time */
	Iminpio		= 67,		/* min. PIO cycle w/o flow control */
	Iminiordy	= 68,		/* min. PIO cycle with IORDY */
	Ipcktbr		= 71,		/* time from PACKET to bus release */
	Iserbsy		= 72,		/* time from SERVICE to !Bsy */
	Iqdepth		= 75,		/* max. queue depth */
	Imajor		= 80,		/* major version number */
	Iminor		= 81,		/* minor version number */
	Icsfs		= 82,		/* command set/feature supported */
	Icsfe		= 85,		/* command set/feature enabled */
	Iudma		= 88,		/* ultra DMA mode */
	Ierase		= 89,		/* time for security erase */
	Ieerase		= 90,		/* time for enhanced security erase */
	Ipower		= 91,		/* current advanced power management */
	Ilba48		= 100,		/* 48-bit LBA size (64 bits in 100-103) */
	Irmsn		= 127,		/* removable status notification */
	Isecstat	= 128,		/* security status */
	Icfapwr		= 160,		/* CFA power mode */
	Imediaserial	= 176,		/* current media serial number */
	Icksum		= 255,		/* checksum */
};

enum {					/* bit masks for config identify info */
	Mpktsz		= 0x0003,	/* packet command size */
	Mincomplete	= 0x0004,	/* incomplete information */
	Mdrq		= 0x0060,	/* DRQ type */
	Mrmdev		= 0x0080,	/* device is removable */
	Mtype		= 0x1F00,	/* device type */
	Mproto		= 0x8000,	/* command protocol */
};

enum {					/* bit masks for capabilities identify info */
	Mdma		= 0x0100,	/* DMA supported */
	Mlba		= 0x0200,	/* LBA supported */
	Mnoiordy	= 0x0400,	/* IORDY may be disabled */
	Miordy		= 0x0800,	/* IORDY supported */
	Msoftrst	= 0x1000,	/* needs soft reset when Bsy */
	Mstdby		= 0x2000,	/* standby supported */
	Mqueueing	= 0x4000,	/* queueing overlap supported */
	Midma		= 0x8000,	/* interleaved DMA supported */
};

enum {					/* bit masks for supported/enabled features */
	Msmart		= 0x0001,
	Msecurity	= 0x0002,
	Mrmmedia	= 0x0004,
	Mpwrmgmt	= 0x0008,
	Mpkt		= 0x0010,
	Mwcache		= 0x0020,
	Mlookahead	= 0x0040,
	Mrelirq		= 0x0080,
	Msvcirq		= 0x0100,
	Mreset		= 0x0200,
	Mprotected	= 0x0400,
	Mwbuf		= 0x1000,
	Mrbuf		= 0x2000,
	Mnop		= 0x4000,
	Mmicrocode	= 0x0001,
	Mqueued		= 0x0002,
	Mcfa		= 0x0004,
	Mapm		= 0x0008,
	Mnotify		= 0x0010,
	Mstandby	= 0x0020,
	Mspinup		= 0x0040,
	Mmaxsec		= 0x0100,
	Mautoacoustic	= 0x0200,
	Maddr48		= 0x0400,
	Mdevconfov	= 0x0800,
	Mflush		= 0x1000,
	Mflush48	= 0x2000,
	Msmarterror	= 0x0001,
	Msmartselftest	= 0x0002,
	Mmserial	= 0x0004,
	Mmpassthru	= 0x0008,
	Mlogging	= 0x0020,
};

typedef struct Ctlr Ctlr;
typedef struct Drive Drive;

typedef struct Prd {			/* Physical Region Descriptor */
	ulong	pa;			/* Physical Base Address */
	int	count;
} Prd;

enum {
	BMspan		= 64*1024,	/* must be power of 2 <= 64*1024 */

	Nprd		= SDmaxio/BMspan+2,
};

typedef struct Ctlr {
	int	cmdport;
	int	ctlport;
	int	irq;
	int	tbdf;
	int	bmiba;			/* bus master interface base address */
	int	maxio;			/* sector count transfer maximum */
	int	span;			/* don't span this boundary with dma */

	Pcidev*	pcidev;
	void	(*ienable)(Ctlr*);
	void	(*idisable)(Ctlr*);
	SDev*	sdev;

	Drive*	drive[2];

	Prd*	prdt;			/* physical region descriptor table */

	QLock;				/* current command */
	Drive*	curdrive;
	int	command;		/* last command issued (debugging) */
	Rendez;
	int	done;

	Lock;				/* register access */
} Ctlr;

typedef struct Drive {
	Ctlr*	ctlr;

	int	dev;
	ushort	info[256];
	int	c;			/* cylinder */
	int	h;			/* head */
	int	s;			/* sector */
	vlong	sectors;		/* total */
	int	secsize;		/* sector size */

	int	dma;			/* DMA R/W possible */
	int	dmactl;
	int	rwm;			/* read/write multiple possible */
	int	rwmctl;

	int	pkt;			/* PACKET device, length of pktcmd */
	uchar	pktcmd[16];
	int	pktdma;			/* this PACKET command using dma */

	uchar	sense[18];
	uchar	inquiry[48];

	QLock;				/* drive access */
	int	command;		/* current command */
	int	write;
	uchar*	data;
	int	dlen;
	uchar*	limit;
	int	count;			/* sectors */
	int	block;			/* R/W bytes per block */
	int	status;
	int	error;
	int	flags;			/* internal flags */
} Drive;

enum {					/* internal flags */
	Lba48		= 0x1,		/* LBA48 mode */
	Lba48always	= 0x2,		/* ... */
};

static void
pc87415ienable(Ctlr* ctlr)
{
	Pcidev *p;
	int x;

	p = ctlr->pcidev;
	if(p == nil)
		return;

	x = pcicfgr32(p, 0x40);
	if(ctlr->cmdport == p->mem[0].bar)
		x &= ~0x00000100;
	else
		x &= ~0x00000200;
	pcicfgw32(p, 0x40, x);
}

static void
atadumpstate(Drive* drive, uchar* cmd, vlong lba, int count)
{
	Prd *prd;
	Pcidev *p;
	Ctlr *ctlr;
	int i, bmiba;

	if(!(DEBUG & DbgSTATE)){
		USED(drive, cmd, lba, count);
		return;
	}

	ctlr = drive->ctlr;
	print("command %2.2uX\n", ctlr->command);
	print("data %8.8p limit %8.8p dlen %d status %uX error %uX\n",
		drive->data, drive->limit, drive->dlen,
		drive->status, drive->error);
	if(cmd != nil){
		print("lba %d -> %lld, count %d -> %d (%d)\n",
			(cmd[2]<<24)|(cmd[3]<<16)|(cmd[4]<<8)|cmd[5], lba,
			(cmd[7]<<8)|cmd[8], count, drive->count);
	}
	if(!(inb(ctlr->ctlport+As) & Bsy)){
		for(i = 1; i < 7; i++)
			print(" 0x%2.2uX", inb(ctlr->cmdport+i));
		print(" 0x%2.2uX\n", inb(ctlr->ctlport+As));
	}
	if(drive->command == Cwd || drive->command == Crd){
		bmiba = ctlr->bmiba;
		prd = ctlr->prdt;
		print("bmicx %2.2uX bmisx %2.2uX prdt %8.8p\n",
			inb(bmiba+Bmicx), inb(bmiba+Bmisx), prd);
		for(;;){
			print("pa 0x%8.8luX count %8.8uX\n",
				prd->pa, prd->count);
			if(prd->count & PrdEOT)
				break;
			prd++;
		}
	}
	if(ctlr->pcidev && ctlr->pcidev->vid == 0x8086){
		p = ctlr->pcidev;
		print("0x40: %4.4uX 0x42: %4.4uX",
			pcicfgr16(p, 0x40), pcicfgr16(p, 0x42));
		print("0x48: %2.2uX\n", pcicfgr8(p, 0x48));
		print("0x4A: %4.4uX\n", pcicfgr16(p, 0x4A));
	}
}

static int
atadebug(int cmdport, int ctlport, char* fmt, ...)
{
	int i, n;
	va_list arg;
	char buf[PRINTSIZE];

	if(!(DEBUG & DbgPROBE)){
		USED(cmdport, ctlport, fmt);
		return 0;
	}

	va_start(arg, fmt);
	n = vseprint(buf, buf+sizeof(buf), fmt, arg) - buf;
	va_end(arg);

	if(cmdport){
		if(buf[n-1] == '\n')
			n--;
		n += snprint(buf+n, PRINTSIZE-n, " ataregs 0x%uX:",
			cmdport);
		for(i = Features; i < Command; i++)
			n += snprint(buf+n, PRINTSIZE-n, " 0x%2.2uX",
				inb(cmdport+i));
		if(ctlport)
			n += snprint(buf+n, PRINTSIZE-n, " 0x%2.2uX",
				inb(ctlport+As));
		n += snprint(buf+n, PRINTSIZE-n, "\n");
	}
	putstrn(buf, n);

	return n;
}

static int
ataready(int cmdport, int ctlport, int dev, int reset, int ready, int micro)
{
	int as;

	atadebug(cmdport, ctlport, "ataready: dev %uX reset %uX ready %uX",
		dev, reset, ready);

	for(;;){
		/*
		 * Wait for the controller to become not busy and
		 * possibly for a status bit to become true (usually
		 * Drdy). Must change to the appropriate device
		 * register set if necessary before testing for ready.
		 * Always run through the loop at least once so it
		 * can be used as a test for !Bsy.
		 */
		as = inb(ctlport+As);
		if(as & reset){
			/* nothing to do */
		}
		else if(dev){
			outb(cmdport+Dh, dev);
			dev = 0;
		}
		else if(ready == 0 || (as & ready)){
			atadebug(0, 0, "ataready: %d 0x%2.2uX\n", micro, as);
			return as;
		}

		if(micro-- <= 0){
			atadebug(0, 0, "ataready: %d 0x%2.2uX\n", micro, as);
			break;
		}
		microdelay(1);
	}
	atadebug(cmdport, ctlport, "ataready: timeout");

	return -1;
}

/*
static int
atacsf(Drive* drive, vlong csf, int supported)
{
	ushort *info;
	int cmdset, i, x;

	if(supported)
		info = &drive->info[Icsfs];
	else
		info = &drive->info[Icsfe];

	for(i = 0; i < 3; i++){
		x = (csf>>(16*i)) & 0xFFFF;
		if(x == 0)
			continue;
		cmdset = info[i];
		if(cmdset == 0 || cmdset == 0xFFFF)
			return 0;
		return cmdset & x;
	}

	return 0;
}
*/

static int
atadone(void* arg)
{
	return ((Ctlr*)arg)->done;
}

static int
atarwmmode(Drive* drive, int cmdport, int ctlport, int dev)
{
	int as, maxrwm, rwm;

	maxrwm = (drive->info[Imaxrwm] & 0xFF);
	if(maxrwm == 0)
		return 0;

	/*
	 * Sometimes drives come up with the current count set
	 * to 0; if so, set a suitable value, otherwise believe
	 * the value in Irwm if the 0x100 bit is set.
	 */
	if(drive->info[Irwm] & 0x100)
		rwm = (drive->info[Irwm] & 0xFF);
	else
		rwm = 0;
	if(rwm == 0)
		rwm = maxrwm;
	if(rwm > 16)
		rwm = 16;
	if(ataready(cmdport, ctlport, dev, Bsy|Drq, Drdy, 102*1000) < 0)
		return 0;
	outb(cmdport+Count, rwm);
	outb(cmdport+Command, Csm);
	microdelay(1);
	as = ataready(cmdport, ctlport, 0, Bsy, Drdy|Df|Err, 1000);
	inb(cmdport+Status);
	if(as < 0 || (as & (Df|Err)))
		return 0;

	drive->rwm = rwm;

	return rwm;
}

static int
atadmamode(Drive* drive)
{
	int dma;

	/*
	 * Check if any DMA mode enabled.
	 * Assumes the BIOS has picked and enabled the best.
	 * This is completely passive at the moment, no attempt is
	 * made to ensure the hardware is correctly set up.
	 */
	dma = drive->info[Imwdma] & 0x0707;
	drive->dma = (dma>>8) & dma;
	if(drive->dma == 0 && (drive->info[Ivalid] & 0x04)){
		dma = drive->info[Iudma] & 0x7F7F;
		drive->dma = (dma>>8) & dma;
		if(drive->dma)
			drive->dma |= 'U'<<16;