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+/* 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/slab.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;
+
+static int __init 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.
+ * We don't do the primary+secondary ID encoding thing here. Maybe we should.
+ * (that would break the topcat detection, though. I need to think about
+ * the whole primary/secondary ID thing.)
+ */
+ int scode;
+ u_char prid;
+
+ 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 */
+
+ /* We aren't very likely to want to use this to get at the IHPIB,
+ * but maybe it's returning the same ID as the card we do want...
+ */
+ if (!DIO_ISIHPIB(scode))
+ prid = DIO_ID(va);
+ else
+ prid = DIO_ID_IHPIB;
+
+ if (prid == deviceid)
+ return scode;
+ }
+ return 0;
+}
+
+/* Aargh: we use 0 for an error return code, but select code 0 exists!
+ * FIXME (trivial, use -1, but requires changes to all the drivers :-< )
+ */
+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.
+ */
+static int __init 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: ipl %d: ID %02X", scode, b->ipl, 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;
+ }
+ return 0;
+}
+
+subsys_initcall(dio_init);
+
+/* 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 (DIO_ISIHPIB(scode))
+ return (void*)DIO_IHPIBADDR;
+
+ 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;
+}