/*
 *	linux/arch/alpha/kernel/core_t2.c
 *
 * Written by Jay A Estabrook (jestabro@amt.tay1.dec.com).
 * December 1996.
 *
 * based on CIA code by David A Rusling (david.rusling@reo.mts.dec.com)
 *
 * Code common to all T2 core logic chips.
 */

#define __EXTERN_INLINE
#include <asm/io.h>
#include <asm/core_t2.h>
#undef __EXTERN_INLINE

#include <linux/types.h>
#include <linux/pci.h>
#include <linux/sched.h>
#include <linux/init.h>

#include <asm/ptrace.h>
#include <asm/delay.h>
#include <asm/mce.h>

#include "proto.h"
#include "pci_impl.h"

/* For dumping initial DMA window settings. */
#define DEBUG_PRINT_INITIAL_SETTINGS 0

/* For dumping final DMA window settings. */
#define DEBUG_PRINT_FINAL_SETTINGS 0

/*
 * By default, we direct-map starting at 2GB, in order to allow the
 * maximum size direct-map window (2GB) to match the maximum amount of
 * memory (2GB) that can be present on SABLEs. But that limits the
 * floppy to DMA only via the scatter/gather window set up for 8MB
 * ISA DMA, since the maximum ISA DMA address is 2GB-1.
 *
 * For now, this seems a reasonable trade-off: even though most SABLEs
 * have less than 1GB of memory, floppy usage/performance will not
 * really be affected by forcing it to go via scatter/gather...
 */
#define T2_DIRECTMAP_2G 1

#if T2_DIRECTMAP_2G
# define T2_DIRECTMAP_START	0x80000000UL
# define T2_DIRECTMAP_LENGTH	0x80000000UL
#else
# define T2_DIRECTMAP_START	0x40000000UL
# define T2_DIRECTMAP_LENGTH	0x40000000UL
#endif

/* The ISA scatter/gather window settings. */
#define T2_ISA_SG_START		0x00800000UL
#define T2_ISA_SG_LENGTH	0x00800000UL

/*
 * NOTE: Herein lie back-to-back mb instructions.  They are magic. 
 * One plausible explanation is that the i/o controller does not properly
 * handle the system transaction.  Another involves timing.  Ho hum.
 */

/*
 * BIOS32-style PCI interface:
 */

#define DEBUG_CONFIG 0

#if DEBUG_CONFIG
# define DBG(args)	printk args
#else
# define DBG(args)
#endif

static volatile unsigned int t2_mcheck_any_expected;
static volatile unsigned int t2_mcheck_last_taken;

/* Place to save the DMA Window registers as set up by SRM
   for restoration during shutdown. */
static struct
{
	struct {
		unsigned long wbase;
		unsigned long wmask;
		unsigned long tbase;
	} window[2];
	unsigned long hae_1;
  	unsigned long hae_2;
	unsigned long hae_3;
	unsigned long hae_4;
	unsigned long hbase;
} t2_saved_config __attribute((common));