/*
* 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/config.h>
#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/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>
#define EISA_MAX_SLOTS 4
#define EISA_MAX_IRQ 16
#define EISA_TO_PHYS(x) (0x00080000 | (x))
#define EISA_TO_KSEG1(x) ((void *) KSEG1ADDR(EISA_TO_PHYS((x))))
#define EIU_MODE_REG 0x0009ffc0
#define EIU_STAT_REG 0x0009ffc4
#define EIU_PREMPT_REG 0x0009ffc8
#define EIU_QUIET_REG 0x0009ffcc
#define EIU_INTRPT_ACK 0x00090004
#define EISA_DMA1_STATUS 8
#define EISA_INT1_CTRL 0x20
#define EISA_INT1_MASK 0x21
#define EISA_INT2_CTRL 0xA0
#define EISA_INT2_MASK 0xA1
#define EISA_DMA2_STATUS 0xD0
#define EISA_DMA2_WRITE_SINGLE 0xD4
#define EISA_EXT_NMI_RESET_CTRL 0x461
#define EISA_INT1_EDGE_LEVEL 0x4D0
#define EISA_INT2_EDGE_LEVEL 0x4D1
#define EISA_VENDOR_ID_OFFSET 0xC80
#define EIU_WRITE_32(x,y) { *((u32 *) KSEG1ADDR(x)) = (u32) (y); mb(); }
#define EIU_READ_8(x) *((u8 *) KSEG1ADDR(x))
#define EISA_WRITE_8(x,y) { *((u8 *) EISA_TO_KSEG1(x)) = (u8) (y); mb(); }
#define EISA_READ_8(x) *((u8 *) EISA_TO_KSEG1(x))
static char *decode_eisa_sig(u8 * sig)
{
static char sig_str[8];
u16 rev;
if (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 void ip22_eisa_intr(int irq, void *dev_id, struct pt_regs *regs)
{
u8 eisa_irq;
u8 dma1, dma2;
eisa_irq = EIU_READ_8(EIU_INTRPT_ACK);
dma1 = EISA_READ_8(EISA_DMA1_STATUS);
dma2 = EISA_READ_8(EISA_DMA2_STATUS);
if (eisa_irq >= EISA_MAX_IRQ) {
/* Oops, Bad Stuff Happened... */
printk(KERN_ERR "eisa_irq %d out of bound\n", eisa_irq);
EISA_WRITE_8(EISA_INT2_CTRL, 0x20);
EISA_WRITE_8(EISA_INT1_CTRL, 0x20);
} else
do_IRQ(eisa_irq, regs);
}
static void enable_eisa1_irq(unsigned int irq)
{
unsigned long flags;
u8 mask;
local_irq_save(flags);
mask = EISA_READ_8(EISA_INT1_MASK);
mask &= ~((u8) (1 << irq));
EISA_WRITE_8(EISA_INT1_MASK, mask);
local_irq_restore(flags);
}
static unsigned int startup_eisa1_irq(unsigned int irq)
{
u8 edge;
/* Only use edge interrupts for EISA */
edge = EISA_READ_8(EISA_INT1_EDGE_LEVEL);
edge &= ~((u8) (1 << irq));
EISA_WRITE_8(EISA_INT1_EDGE_LEVEL, edge);
enable_eisa1_irq(irq);
return 0;
}
static void disable_eisa1_irq(unsigned int irq)
{
u8 mask;
mask = EISA_READ_8(EISA_INT1_MASK);
mask |= ((u8) (1 << irq));
EISA_WRITE_8(EISA_INT1_MASK, mask);
}
#define shutdown_eisa1_irq disable_eisa1_irq
static void mask_and_ack_eisa1_irq(unsigned int irq)
{
disable_eisa1_irq(irq);
EISA_WRITE_8(EISA_INT1_CTRL, 0x20);
}
static void end_eisa1_irq(unsigned int irq)
{
if (!(irq_desc[irq].status & (IRQ_DISABLED | IRQ_INPROGRESS)))
enable_eisa1_irq(irq);
}
static struct hw_interrupt_type ip22_eisa1_irq_type = {
.typename = "IP22 EISA",
.startup = startup_eisa1_irq,
.shutdown = shutdown_eisa1_irq,
.enable = enable_eisa1_irq,
.disable = disable_eisa1_irq,
.ack = mask_and_ack_eisa1_irq,
.end = end_eisa1_irq,
};
static void enable_eisa2_irq(unsigned int irq)
{
unsigned long flags;
u8 mask;
local_irq_save(flags);
mask = EISA_READ_8(EISA_INT2_MASK);
mask &= ~((u8) (1 << (irq - 8)));
EISA_WRITE_8(EISA_INT2_MASK, mask);
local_irq_restore(flags);
}
static unsigned int startup_eisa2_irq(unsigned int irq)
{
u8 edge;
/* Only use edge interrupts for EISA */
edge = EISA_READ_8(EISA_INT2_EDGE_LEVEL);
edge &= ~((u8) (1 << (irq - 8)));
EISA_WRITE_8(EISA_INT2_EDGE_LEVEL, edge);
enable_eisa2_irq(irq);
return 0;
}
static void disable_eisa2_irq(unsigned int irq)
{
u8 mask;
mask = EISA_READ_8(EISA_INT2_MASK);
mask |= ((u8) (1 << (irq - 8)));
EISA_WRITE_8(EISA_INT2_MASK, mask);
}
#define shutdown_eisa2_irq disable_eisa2_irq
static void mask_and_ack_eisa2_irq(unsigned int irq)
{
disable_eisa2_irq(irq);
EISA_WRITE_8(EISA_INT2_CTRL, 0x20);
EISA_WRITE_8(EISA_INT1_CTRL, 0x20);
}
static void end_eisa2_irq(unsigned int irq)
{
if (!(irq_desc[irq].status & (IRQ_DISABLED | IRQ_INPROGRESS)))
enable_eisa2_irq(irq);
}
static struct hw_interrupt_type ip22_eisa2_irq_type = {
.typename = "IP22 EISA",
.startup = startup_eisa2_irq,
.shutdown = shutdown_eisa2_irq,
.enable = enable_eisa2_irq,
.disable = disable_eisa2_irq,
.ack = mask_and_ack_eisa2_irq,
.end = end_eisa2_irq,
};
static struct irqaction eisa_action = {
.handler = ip22_eisa_intr,
.name = "EISA",
};
static struct irqaction cascade_action = {
.handler = no_action,
.name = "EISA cascade",
};
int __init ip22_eisa_init(void)
{
int i, c;
char *str;
u8 *slot_addr;
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 <= EISA_MAX_SLOTS; i++) {
slot_addr =
(u8 *) EISA_TO_KSEG1((0x1000 * i) +
EISA_VENDOR_ID_OFFSET);
if ((str = decode_eisa_sig(slot_addr))) {
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 */
EIU_WRITE_32(EIU_PREMPT_REG, 0x0000FFFF);
EIU_WRITE_32(EIU_QUIET_REG, 1);
EIU_WRITE_32(EIU_MODE_REG, 0x40f3c07F);
/* Now be nice to the EISA chipset */
EISA_WRITE_8(EISA_EXT_NMI_RESET_CTRL, 1);
for (i = 0; i < 10000; i++); /* Wait long enough for the dust to settle */
EISA_WRITE_8(EISA_EXT_NMI_RESET_CTRL, 0);
EISA_WRITE_8(EISA_INT1_CTRL, 0x11);
EISA_WRITE_8(EISA_INT2_CTRL, 0x11);
EISA_WRITE_8(EISA_INT1_MASK, 0);
EISA_WRITE_8(EISA_INT2_MASK, 8);
EISA_WRITE_8(EISA_INT1_MASK, 4);
EISA_WRITE_8(EISA_INT2_MASK, 2);
EISA_WRITE_8(EISA_INT1_MASK, 1);
EISA_WRITE_8(EISA_INT2_MASK, 1);
EISA_WRITE_8(EISA_INT1_MASK, 0xfb);
EISA_WRITE_8(EISA_INT2_MASK, 0xff);
EISA_WRITE_8(EISA_DMA2_WRITE_SINGLE, 0);
for (i = SGINT_EISA; i < (SGINT_EISA + EISA_MAX_IRQ); i++) {
irq_desc[i].status = IRQ_DISABLED;
irq_desc[i].action = 0;
irq_desc[i].depth = 1;
if (i < (SGINT_EISA + 8))
irq_desc[i].handler = &ip22_eisa1_irq_type;
else
irq_desc[i].handler = &ip22_eisa2_irq_type;
}
/* 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);
setup_irq(SGINT_EISA + 2, &cascade_action);
EISA_bus = 1;
return 0;
}
