diff options
Diffstat (limited to 'arch/mips/sgi-ip22/ip22-eisa.c')
| -rw-r--r-- | arch/mips/sgi-ip22/ip22-eisa.c | 145 |
1 files changed, 145 insertions, 0 deletions
diff --git a/arch/mips/sgi-ip22/ip22-eisa.c b/arch/mips/sgi-ip22/ip22-eisa.c new file mode 100644 index 000000000..a0a79222c --- /dev/null +++ b/arch/mips/sgi-ip22/ip22-eisa.c @@ -0,0 +1,145 @@ +/* + * Basic EISA bus support for the SGI Indigo-2. + * + * (C) 2002 Pascal Dameme <netinet@freesurf.fr> + * and Marc Zyngier <mzyngier@freesurf.fr> + * + * This code is released under both the GPL version 2 and BSD + * licenses. Either license may be used. + * + * This code offers a very basic support for this EISA bus present in + * the SGI Indigo-2. It currently only supports PIO (forget about DMA + * for the time being). This is enough for a low-end ethernet card, + * but forget about your favorite SCSI card... + * + * TODO : + * - Fix bugs... + * - Add ISA support + * - Add DMA (yeah, right...). + * - Fix more bugs. + */ + +#include <linux/eisa.h> +#include <linux/types.h> +#include <linux/init.h> +#include <linux/irq.h> +#include <linux/kernel_stat.h> +#include <linux/signal.h> +#include <linux/sched.h> +#include <linux/interrupt.h> +#include <linux/delay.h> +#include <asm/io.h> +#include <asm/irq.h> +#include <asm/mipsregs.h> +#include <asm/addrspace.h> +#include <asm/processor.h> +#include <asm/sgi/ioc.h> +#include <asm/sgi/mc.h> +#include <asm/sgi/ip22.h> +#include <asm/i8259.h> + +/* I2 has four EISA slots. */ +#define IP22_EISA_MAX_SLOTS 4 +#define EISA_MAX_IRQ 16 + +#define EIU_MODE_REG 0x0001ffc0 +#define EIU_STAT_REG 0x0001ffc4 +#define EIU_PREMPT_REG 0x0001ffc8 +#define EIU_QUIET_REG 0x0001ffcc +#define EIU_INTRPT_ACK 0x00010004 + +static char __init *decode_eisa_sig(unsigned long addr) +{ + static char sig_str[EISA_SIG_LEN] __initdata; + u8 sig[4]; + u16 rev; + int i; + + for (i = 0; i < 4; i++) { + sig[i] = inb(addr + i); + + if (!i && (sig[0] & 0x80)) + return NULL; + } + + sig_str[0] = ((sig[0] >> 2) & 0x1f) + ('A' - 1); + sig_str[1] = (((sig[0] & 3) << 3) | (sig[1] >> 5)) + ('A' - 1); + sig_str[2] = (sig[1] & 0x1f) + ('A' - 1); + rev = (sig[2] << 8) | sig[3]; + sprintf(sig_str + 3, "%04X", rev); + + return sig_str; +} + +static irqreturn_t ip22_eisa_intr(int irq, void *dev_id) +{ + u8 eisa_irq = inb(EIU_INTRPT_ACK); + + inb(EISA_DMA1_STATUS); + inb(EISA_DMA2_STATUS); + + if (eisa_irq < EISA_MAX_IRQ) { + do_IRQ(eisa_irq); + return IRQ_HANDLED; + } + + /* Oops, Bad Stuff Happened... */ + printk(KERN_ERR "eisa_irq %d out of bound\n", eisa_irq); + + outb(0x20, EISA_INT2_CTRL); + outb(0x20, EISA_INT1_CTRL); + + return IRQ_NONE; +} + +static struct irqaction eisa_action = { + .handler = ip22_eisa_intr, + .name = "EISA", +}; + +int __init ip22_eisa_init(void) +{ + int i, c; + char *str; + + if (!(sgimc->systemid & SGIMC_SYSID_EPRESENT)) { + printk(KERN_INFO "EISA: bus not present.\n"); + return 1; + } + + printk(KERN_INFO "EISA: Probing bus...\n"); + for (c = 0, i = 1; i <= IP22_EISA_MAX_SLOTS; i++) { + if ((str = decode_eisa_sig(0x1000 * i + EISA_VENDOR_ID_OFFSET))) { + printk(KERN_INFO "EISA: slot %d : %s detected.\n", + i, str); + c++; + } + } + printk(KERN_INFO "EISA: Detected %d card%s.\n", c, c < 2 ? "" : "s"); +#ifdef CONFIG_ISA + printk(KERN_INFO "ISA support compiled in.\n"); +#endif + + /* Warning : BlackMagicAhead(tm). + Please wave your favorite dead chicken over the busses */ + + /* First say hello to the EIU */ + outl(0x0000FFFF, EIU_PREMPT_REG); + outl(1, EIU_QUIET_REG); + outl(0x40f3c07F, EIU_MODE_REG); + + /* Now be nice to the EISA chipset */ + outb(1, EISA_EXT_NMI_RESET_CTRL); + udelay(50); /* Wait long enough for the dust to settle */ + outb(0, EISA_EXT_NMI_RESET_CTRL); + outb(0, EISA_DMA2_WRITE_SINGLE); + + init_i8259_irqs(); + + /* Cannot use request_irq because of kmalloc not being ready at such + * an early stage. Yes, I've been bitten... */ + setup_irq(SGI_EISA_IRQ, &eisa_action); + + EISA_bus = 1; + return 0; +} |