ide-jasper.c

这是一个SIGMA方案的PMP播放器的UCLINUX程序,可播放DVD,VCD,CD MP3...有很好的参考价值.

/* ide-jasper.c */

/* jasper specific initialization stuff for ide */

#include <linux/init.h>
#include <asm/io.h>
#include <asm/hardware.h>
#include <linux/ide.h>
#include "ide_modes.h"

extern int printk(const char *fmt,...);
extern void ide_setup_dma (ide_hwif_t *hwif, unsigned long dma_base, unsigned int num_ports);

#define ENABLE_BMDMA 
// #undef ENABLE_BMDMA
//#define ENABLE_UDMA 
#undef ENABLE_UDMA

int ide_config_drive_speed (ide_drive_t *drive, byte speed);

//Setup register 0x54 and 0x58a for UDMA timing
//Values assume 100Mhz system bus
static int jasper_tune_chipset(ide_drive_t *drive, byte speed)
{
	ide_hwif_t *hwif = HWIF(drive);
	char channel     = hwif->channel;
	unsigned short reg54, reg58;
	int slave = 0;

	printk("jasper_tune_chipset: speed = %02x\n", speed);
	
	reg54=inw(JASPER_IDE_BASE + 0x54);
	reg58=inw(JASPER_IDE_BASE + 0x58);

#ifdef ENABLE_UDMA 
	if(speed>=XFER_UDMA_0 && speed<=XFER_UDMA_5){
		// ---- This assume 100Mhz system bus - for UDMA
		if(slave) {
			reg54 |= 0x2;
			reg58 |= (speed-XFER_UDMA_0)<<4;
		}else {
			reg54 |= 0x1;
			reg58 |= (speed-XFER_UDMA_0);
		}
		// ---- 
	} else
#endif // ENABLE_UDMA			
	{
		if(slave) {
			reg54 &= ~0x2;
		} else {
			reg54 &= ~0x1;
		}
	}
	
	outw(reg54, JASPER_IDE_BASE + 0x54);
	outw(reg58, JASPER_IDE_BASE + 0x58);
	return ide_config_drive_speed(drive, speed);
}

static int jasper_config_drive_for_dma (ide_drive_t *drive)
{
	struct hd_driveid *id = drive->id;
	ide_hwif_t *hwif = HWIF(drive);
	int autodma = hwif->autodma;
	ide_dma_action_t dma_func = ide_dma_on;
	byte speed;
	byte udma_66 = eighty_ninty_three(drive); // 80 c ribbon ?

	printk ("jasper_config_drive_for_dma:\n");
	printk (" capability    = 0x%04x\n", id->capability);
	printk (" field_valid   = 0x%04x\n", id->field_valid);
	printk (" dma_ultra     = 0x%04x\n", id->dma_ultra);
	printk (" dma_1word (s) = 0x%04x\n", id->dma_1word);
	printk (" dma_mword (m) = 0x%04x\n", id->dma_mword);
	printk (" autodma       = 0x%04x\n", autodma);
	if (id && (id->capability & 1) && autodma) {
		if (ide_dmaproc(ide_dma_bad_drive, drive)) {
			// consult list of known "bad" drives
			dma_func = ide_dma_off;
// Ultra DMA support			
#ifdef ENABLE_UDMA
		} else if ((id->field_valid & 4) && (id->dma_ultra & 0x3F)) {
			// Enable DMA on any drive that is UltraDMA (mode 0-5) capable
			// mode3/4/5 needs 80c ribbon
			if((id->dma_ultra & 0x20) && udma_66)
				speed = XFER_UDMA_5; 
			else if((id->dma_ultra & 0x10) && udma_66)
				speed = XFER_UDMA_4;
			else if((id->dma_ultra & 0x08) && udma_66)
				speed = XFER_UDMA_3;
			else if(id->dma_ultra & 0x04)
				speed = XFER_UDMA_2;
			else if(id->dma_ultra & 0x02)
				speed = XFER_UDMA_1;
			else if(id->dma_ultra & 0x01)
				speed = XFER_UDMA_0;
#endif			
//Busmaster DMA support
#ifdef ENABLE_BMDMA
		} else if((id->field_valid & 2) &&	(id->dma_mword & 0x7)) {
			// Multiword DMA
			if(id->dma_mword & 0x4)
				speed = XFER_MW_DMA_2;
			else if (id->dma_mword & 0x2)
				speed = XFER_MW_DMA_1;
			else
				speed = XFER_MW_DMA_0;
		} else if((id->field_valid & 2) && (id->dma_1word & 0x7)) {
			// Single word DMA
			if(id->dma_1word & 0x4)
				speed = XFER_SW_DMA_2;
			else if (id->dma_1word & 0x2)
				speed = XFER_SW_DMA_1;
			else 
				speed = XFER_SW_DMA_0;
#endif			
		} else {
			speed = XFER_PIO_0 + ide_get_best_pio_mode(drive, 255, 5, NULL);
			dma_func = ide_dma_off_quietly;
		}

		if(jasper_tune_chipset(drive, speed)) {
			printk("Error in jasper_tune_chipset, disbale DMA\n");
			dma_func = ide_dma_off;
		}
		
		return hwif->dmaproc(dma_func, drive);
	}
	
	printk ("DMA disabled quietly\n");
	return hwif->dmaproc(ide_dma_off_quietly, drive);
}

static int jasper_dmaproc(ide_dma_action_t func, ide_drive_t *drive)
{
	unsigned char dma_stat;
	unsigned long dma_base = HWIF(drive)->dma_base;
	unsigned long dma_count, dma_address;
	int i;
	
	switch (func) {
		case ide_dma_check:
			return jasper_config_drive_for_dma(drive);
		case ide_dma_end:
			drive->waiting_for_dma=0;
			for(i=0; i<100; i++) {
				dma_stat = inb(dma_base + 0x4);  /* get DMA status */
				if((dma_stat & 0x4) ==4)
					break;
				dma_count = inl(dma_base + 0xe4);
				dma_address = inl(dma_base + 0xe0);
				printk("J %1x %08x %04x\n", dma_stat & 0xF, dma_address, dma_count);
			}
			outb(inb(dma_base)&~1, dma_base); /* stop DMA */
			outb(dma_stat|6, dma_base + 0x4); /* clear the INTR & ERROR bits */
			ide_destroy_dmatable(drive); /* purge DMA mappings */
			return (dma_stat & 4) != 4 ? (0x10 | dma_stat) : 0;
		default :
			break;
	}
	/* Other cases are done by generic IDE-DMA code. */
	return ide_dmaproc(func, drive);
}

void __init jasper_ide_init(void)
{
	ide_hwif_t *hwif;
	unsigned long dma_base = JASPER_IDE_DMA_BASE;
	// enable ide interface 
	
	//set pio4 to 1
	
	outl(0x0010FFFF, JASPER_PIO0_BASE + PIO_DIR);
	outl(0x0010FFFF, JASPER_PIO0_BASE + PIO_DATA);

	//	choose ide over dvd loader (DVD_AV_CONTROL)
	//	write 0x8000 to IDETIM
	outl(0x00, JASPER_DVD_BASE + DVD_AV_CTRL);			//0x00 select IDE over DVD-loader
	outl(0x8000, JASPER_IDE_BASE + IDE_TIM);
//	outl(0xb301, JASPER_IDE_BASE + IDE_TIM);		//0x40 IDE decode enable

	printk("JASPER ide controller activated\n");
	
	// grab hwif,
	hwif = &ide_hwifs[0];
	// setup busmaster dma
	ide_setup_dma(hwif, dma_base, 16);
	// override dmaproc
 	hwif->dmaproc = &jasper_dmaproc;
	// autodma on
	hwif->autodma = 1;
}