diff options
Diffstat (limited to 'drivers/dio/dio.c')
| -rw-r--r-- | drivers/dio/dio.c | 292 |
1 files changed, 292 insertions, 0 deletions
diff --git a/drivers/dio/dio.c b/drivers/dio/dio.c new file mode 100644 index 000000000..eaab1ab1f --- /dev/null +++ b/drivers/dio/dio.c @@ -0,0 +1,292 @@ +/* Code to support devices on the DIO (and eventually DIO-II) bus + * Copyright (C) 05/1998 Peter Maydell <pmaydell@chiark.greenend.org.uk> + * + * This code has basically these routines at the moment: + * int dio_find(u_int deviceid) + * Search the list of DIO devices and return the select code + * of the next unconfigured device found that matches the given device ID. + * Note that the deviceid parameter should be the encoded ID. + * This means that framebuffers should pass it as + * DIO_ENCODE_ID(DIO_ID_FBUFFER,DIO_ID2_TOPCAT) + * (or whatever); everybody else just uses DIO_ID_FOOBAR. + * void *dio_scodetoviraddr(int scode) + * Return the virtual address corresponding to the given select code. + * NB: DIO-II devices will have to be mapped in in this routine! + * int dio_scodetoipl(int scode) + * Every DIO card has a fixed interrupt priority level. This function + * returns it, whatever it is. + * const char *dio_scodetoname(int scode) + * Return a character string describing this board [might be "" if + * not CONFIG_DIO_CONSTANTS] + * void dio_config_board(int scode) mark board as configured in the list + * void dio_unconfig_board(int scode) mark board as no longer configured + * + * This file is based on the way the Amiga port handles Zorro II cards, + * although we aren't so complicated... + */ +#include <linux/config.h> +#include <linux/kernel.h> +#include <linux/types.h> +#include <linux/dio.h> +#include <linux/malloc.h> /* kmalloc() */ +#include <linux/init.h> +#include <asm/hwtest.h> /* hwreg_present() */ +#include <asm/io.h> /* readb() */ +/* not a real config option yet! */ +#define CONFIG_DIO_CONSTANTS + +#ifdef CONFIG_DIO_CONSTANTS +/* We associate each numeric ID with an appropriate descriptive string + * using a constant array of these structs. + * FIXME: we should be able to arrange to throw away most of the strings + * using the initdata stuff. Then we wouldn't need to worry about + * carrying them around... + * I think we do this by copying them into newly kmalloc()ed memory and + * marking the names[] array as .initdata ? + */ +struct dioname +{ + int id; + const char *name; +}; + +/* useful macro */ +#define DIONAME(x) { DIO_ID_##x, DIO_DESC_##x } +#define DIOFBNAME(x) { DIO_ENCODE_ID( DIO_ID_FBUFFER, DIO_ID2_##x), DIO_DESC2_##x } + +static struct dioname names[] = +{ + DIONAME(DCA0), DIONAME(DCA0REM), DIONAME(DCA1), DIONAME(DCA1REM), + DIONAME(DCM), DIONAME(DCMREM), + DIONAME(LAN), + DIONAME(FHPIB), DIONAME(NHPIB), DIONAME(IHPIB), + DIONAME(SCSI0), DIONAME(SCSI1), DIONAME(SCSI2), DIONAME(SCSI3), + DIONAME(FBUFFER), + DIONAME(PARALLEL), DIONAME(VME), DIONAME(DCL), DIONAME(DCLREM), + DIONAME(MISC0), DIONAME(MISC1), DIONAME(MISC2), DIONAME(MISC3), + DIONAME(MISC4), DIONAME(MISC5), DIONAME(MISC6), DIONAME(MISC7), + DIONAME(MISC8), DIONAME(MISC9), DIONAME(MISC10), DIONAME(MISC11), + DIONAME(MISC12), DIONAME(MISC13), + DIOFBNAME(GATORBOX), DIOFBNAME(TOPCAT), DIOFBNAME(RENAISSANCE), + DIOFBNAME(LRCATSEYE), DIOFBNAME(HRCCATSEYE), DIOFBNAME(HRMCATSEYE), + DIOFBNAME(DAVINCI), DIOFBNAME(XXXCATSEYE), DIOFBNAME(HYPERION), + DIOFBNAME(XGENESIS), DIOFBNAME(TIGER), DIOFBNAME(YGENESIS) +}; + +#undef DIONAME +#undef DIOFBNAME + +#define NUMNAMES (sizeof(names) / sizeof(struct dioname)) + +static const char *unknowndioname + = "unknown DIO board -- please email <pmaydell@chiark.greenend.org.uk>!"; + +static const char *dio_getname(int id) +{ + /* return pointer to a constant string describing the board with given ID */ + unsigned int i; + for (i = 0; i < NUMNAMES; i++) + if (names[i].id == id) + return names[i].name; + + return unknowndioname; +} + +#else + +static char dio_no_name[] = { 0 }; +#define dio_getname(_id) (dio_no_name) + +#endif /* CONFIG_DIO_CONSTANTS */ + +/* We represent all the DIO boards in the system with a linked list of these structs. */ +struct dioboard +{ + struct dioboard *next; /* link to next struct in list */ + int ipl; /* IPL of this board */ + int configured; /* has this board been configured? */ + int scode; /* select code of this board */ + int id; /* encoded ID */ + const char *name; +}; + +static struct dioboard *blist = NULL; + +__initfunc(static int dio_find_slow(int deviceid)) +{ + /* Called to find a DIO device before the full bus scan has run. Basically + only used by the console driver. */ + int scode; + for (scode = 0; scode < DIO_SCMAX; scode++) + { + void *va; + + if (DIO_SCINHOLE(scode)) + continue; + + va = dio_scodetoviraddr(scode); + if (!va || !hwreg_present(va + DIO_IDOFF)) + continue; /* no board present at that select code */ + + if (DIO_ID(va) == deviceid) + return scode; + } + return 0; +} + +int dio_find(int deviceid) +{ + if (blist) + { + /* fast way */ + struct dioboard *b; + for (b = blist; b; b = b->next) + if (b->id == deviceid && b->configured == 0) + return b->scode; + return 0; + } + return dio_find_slow(deviceid); +} + +/* This is the function that scans the DIO space and works out what + * hardware is actually present. + */ +__initfunc(void dio_init(void)) +{ + int scode; + struct dioboard *b, *bprev = NULL; + + printk("Scanning for DIO devices...\n"); + + for (scode = 0; scode < DIO_SCMAX; ++scode) + { + u_char prid, secid = 0; /* primary, secondary ID bytes */ + u_char *va; + + if (DIO_SCINHOLE(scode)) + continue; + + va = dio_scodetoviraddr(scode); + if (!va || !hwreg_present(va + DIO_IDOFF)) + continue; /* no board present at that select code */ + + /* Found a board, allocate it an entry in the list */ + b = kmalloc(sizeof(struct dioboard), GFP_KERNEL); + + /* read the ID byte(s) and encode if necessary. Note workaround + * for broken internal HPIB devices... + */ + if (!DIO_ISIHPIB(scode)) + prid = DIO_ID(va); + else + prid = DIO_ID_IHPIB; + + if (DIO_NEEDSSECID(prid)) + { + secid = DIO_SECID(va); + b->id = DIO_ENCODE_ID(prid, secid); + } + else + b->id = prid; + + b->configured = 0; + b->scode = scode; + b->ipl = DIO_IPL(va); + b->name = dio_getname(b->id); + printk("select code %3d: ID %02X", scode, prid); + if (DIO_NEEDSSECID(b->id)) + printk(":%02X", secid); + printk(" %s\n", b->name); + + b->next = NULL; + + if (bprev) + bprev->next = b; + else + blist = b; + bprev = b; + } +} + +/* Bear in mind that this is called in the very early stages of initialisation + * in order to get the virtual address of the serial port for the console... + */ +void *dio_scodetoviraddr(int scode) +{ + if (scode > DIOII_SCBASE) + { + printk("dio_scodetoviraddr: don't support DIO-II yet!\n"); + return 0; + } + else if (scode > DIO_SCMAX || scode < 0) + return 0; + else if (DIO_SCINHOLE(scode)) + return 0; + else if (scode == DIO_IHPIBSCODE) /* this should really be #ifdef CONFIG_IHPIB */ + return (void*)DIO_IHPIBADDR; /* or something similar... */ + + return (void*)(DIO_VIRADDRBASE + DIO_BASE + scode * 0x10000); +} + +int dio_scodetoipl(int scode) +{ + struct dioboard *b; + for (b = blist; b; b = b->next) + if (b->scode == scode) + break; + + if (!b) + { + printk("dio_scodetoipl: bad select code %d\n", scode); + return 0; + } + else + return b->ipl; +} + +const char *dio_scodetoname(int scode) +{ + struct dioboard *b; + for (b = blist; b; b = b->next) + if (b->scode == scode) + break; + + if (!b) + { + printk("dio_scodetoname: bad select code %d\n", scode); + return NULL; + } + else + return b->name; +} + +void dio_config_board(int scode) +{ + struct dioboard *b; + for (b = blist; b; b = b->next) + if (b->scode == scode) + break; + + if (!b) + printk("dio_config_board: bad select code %d\n", scode); + else if (b->configured) + printk("dio_config_board: board at select code %d already configured\n", scode); + else + b->configured = 1; +} + +void dio_unconfig_board(int scode) +{ + struct dioboard *b; + for (b = blist; b; b = b->next) + if (b->scode == scode) + break; + + if (!b) + printk("dio_unconfig_board: bad select code %d\n", scode); + else if (!b->configured) + printk("dio_unconfig_board: board at select code %d not configured\n", + scode); + else + b->configured = 0; +} |