aboutsummaryrefslogtreecommitdiff
path: root/drivers/mtd/devices/docprobe.c
diff options
context:
space:
mode:
Diffstat (limited to 'drivers/mtd/devices/docprobe.c')
-rw-r--r--drivers/mtd/devices/docprobe.c355
1 files changed, 355 insertions, 0 deletions
diff --git a/drivers/mtd/devices/docprobe.c b/drivers/mtd/devices/docprobe.c
new file mode 100644
index 00000000000..197d67045e1
--- /dev/null
+++ b/drivers/mtd/devices/docprobe.c
@@ -0,0 +1,355 @@
+
+/* Linux driver for Disk-On-Chip devices */
+/* Probe routines common to all DoC devices */
+/* (C) 1999 Machine Vision Holdings, Inc. */
+/* (C) 1999-2003 David Woodhouse <dwmw2@infradead.org> */
+
+/* $Id: docprobe.c,v 1.44 2005/01/05 12:40:36 dwmw2 Exp $ */
+
+
+
+/* DOC_PASSIVE_PROBE:
+ In order to ensure that the BIOS checksum is correct at boot time, and
+ hence that the onboard BIOS extension gets executed, the DiskOnChip
+ goes into reset mode when it is read sequentially: all registers
+ return 0xff until the chip is woken up again by writing to the
+ DOCControl register.
+
+ Unfortunately, this means that the probe for the DiskOnChip is unsafe,
+ because one of the first things it does is write to where it thinks
+ the DOCControl register should be - which may well be shared memory
+ for another device. I've had machines which lock up when this is
+ attempted. Hence the possibility to do a passive probe, which will fail
+ to detect a chip in reset mode, but is at least guaranteed not to lock
+ the machine.
+
+ If you have this problem, uncomment the following line:
+#define DOC_PASSIVE_PROBE
+*/
+
+
+/* DOC_SINGLE_DRIVER:
+ Millennium driver has been merged into DOC2000 driver.
+
+ The old Millennium-only driver has been retained just in case there
+ are problems with the new code. If the combined driver doesn't work
+ for you, you can try the old one by undefining DOC_SINGLE_DRIVER
+ below and also enabling it in your configuration. If this fixes the
+ problems, please send a report to the MTD mailing list at
+ <linux-mtd@lists.infradead.org>.
+*/
+#define DOC_SINGLE_DRIVER
+
+#include <linux/config.h>
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <asm/errno.h>
+#include <asm/io.h>
+#include <linux/delay.h>
+#include <linux/slab.h>
+#include <linux/init.h>
+#include <linux/types.h>
+
+#include <linux/mtd/mtd.h>
+#include <linux/mtd/nand.h>
+#include <linux/mtd/doc2000.h>
+#include <linux/mtd/compatmac.h>
+
+/* Where to look for the devices? */
+#ifndef CONFIG_MTD_DOCPROBE_ADDRESS
+#define CONFIG_MTD_DOCPROBE_ADDRESS 0
+#endif
+
+
+static unsigned long doc_config_location = CONFIG_MTD_DOCPROBE_ADDRESS;
+module_param(doc_config_location, ulong, 0);
+MODULE_PARM_DESC(doc_config_location, "Physical memory address at which to probe for DiskOnChip");
+
+static unsigned long __initdata doc_locations[] = {
+#if defined (__alpha__) || defined(__i386__) || defined(__x86_64__)
+#ifdef CONFIG_MTD_DOCPROBE_HIGH
+ 0xfffc8000, 0xfffca000, 0xfffcc000, 0xfffce000,
+ 0xfffd0000, 0xfffd2000, 0xfffd4000, 0xfffd6000,
+ 0xfffd8000, 0xfffda000, 0xfffdc000, 0xfffde000,
+ 0xfffe0000, 0xfffe2000, 0xfffe4000, 0xfffe6000,
+ 0xfffe8000, 0xfffea000, 0xfffec000, 0xfffee000,
+#else /* CONFIG_MTD_DOCPROBE_HIGH */
+ 0xc8000, 0xca000, 0xcc000, 0xce000,
+ 0xd0000, 0xd2000, 0xd4000, 0xd6000,
+ 0xd8000, 0xda000, 0xdc000, 0xde000,
+ 0xe0000, 0xe2000, 0xe4000, 0xe6000,
+ 0xe8000, 0xea000, 0xec000, 0xee000,
+#endif /* CONFIG_MTD_DOCPROBE_HIGH */
+#elif defined(__PPC__)
+ 0xe4000000,
+#elif defined(CONFIG_MOMENCO_OCELOT)
+ 0x2f000000,
+ 0xff000000,
+#elif defined(CONFIG_MOMENCO_OCELOT_G) || defined (CONFIG_MOMENCO_OCELOT_C)
+ 0xff000000,
+##else
+#warning Unknown architecture for DiskOnChip. No default probe locations defined
+#endif
+ 0xffffffff };
+
+/* doccheck: Probe a given memory window to see if there's a DiskOnChip present */
+
+static inline int __init doccheck(void __iomem *potential, unsigned long physadr)
+{
+ void __iomem *window=potential;
+ unsigned char tmp, tmpb, tmpc, ChipID;
+#ifndef DOC_PASSIVE_PROBE
+ unsigned char tmp2;
+#endif
+
+ /* Routine copied from the Linux DOC driver */
+
+#ifdef CONFIG_MTD_DOCPROBE_55AA
+ /* Check for 0x55 0xAA signature at beginning of window,
+ this is no longer true once we remove the IPL (for Millennium */
+ if (ReadDOC(window, Sig1) != 0x55 || ReadDOC(window, Sig2) != 0xaa)
+ return 0;
+#endif /* CONFIG_MTD_DOCPROBE_55AA */
+
+#ifndef DOC_PASSIVE_PROBE
+ /* It's not possible to cleanly detect the DiskOnChip - the
+ * bootup procedure will put the device into reset mode, and
+ * it's not possible to talk to it without actually writing
+ * to the DOCControl register. So we store the current contents
+ * of the DOCControl register's location, in case we later decide
+ * that it's not a DiskOnChip, and want to put it back how we
+ * found it.
+ */
+ tmp2 = ReadDOC(window, DOCControl);
+
+ /* Reset the DiskOnChip ASIC */
+ WriteDOC(DOC_MODE_CLR_ERR | DOC_MODE_MDWREN | DOC_MODE_RESET,
+ window, DOCControl);
+ WriteDOC(DOC_MODE_CLR_ERR | DOC_MODE_MDWREN | DOC_MODE_RESET,
+ window, DOCControl);
+
+ /* Enable the DiskOnChip ASIC */
+ WriteDOC(DOC_MODE_CLR_ERR | DOC_MODE_MDWREN | DOC_MODE_NORMAL,
+ window, DOCControl);
+ WriteDOC(DOC_MODE_CLR_ERR | DOC_MODE_MDWREN | DOC_MODE_NORMAL,
+ window, DOCControl);
+#endif /* !DOC_PASSIVE_PROBE */
+
+ /* We need to read the ChipID register four times. For some
+ newer DiskOnChip 2000 units, the first three reads will
+ return the DiskOnChip Millennium ident. Don't ask. */
+ ChipID = ReadDOC(window, ChipID);
+
+ switch (ChipID) {
+ case DOC_ChipID_Doc2k:
+ /* Check the TOGGLE bit in the ECC register */
+ tmp = ReadDOC(window, 2k_ECCStatus) & DOC_TOGGLE_BIT;
+ tmpb = ReadDOC(window, 2k_ECCStatus) & DOC_TOGGLE_BIT;
+ tmpc = ReadDOC(window, 2k_ECCStatus) & DOC_TOGGLE_BIT;
+ if (tmp != tmpb && tmp == tmpc)
+ return ChipID;
+ break;
+
+ case DOC_ChipID_DocMil:
+ /* Check for the new 2000 with Millennium ASIC */
+ ReadDOC(window, ChipID);
+ ReadDOC(window, ChipID);
+ if (ReadDOC(window, ChipID) != DOC_ChipID_DocMil)
+ ChipID = DOC_ChipID_Doc2kTSOP;
+
+ /* Check the TOGGLE bit in the ECC register */
+ tmp = ReadDOC(window, ECCConf) & DOC_TOGGLE_BIT;
+ tmpb = ReadDOC(window, ECCConf) & DOC_TOGGLE_BIT;
+ tmpc = ReadDOC(window, ECCConf) & DOC_TOGGLE_BIT;
+ if (tmp != tmpb && tmp == tmpc)
+ return ChipID;
+ break;
+
+ case DOC_ChipID_DocMilPlus16:
+ case DOC_ChipID_DocMilPlus32:
+ case 0:
+ /* Possible Millennium+, need to do more checks */
+#ifndef DOC_PASSIVE_PROBE
+ /* Possibly release from power down mode */
+ for (tmp = 0; (tmp < 4); tmp++)
+ ReadDOC(window, Mplus_Power);
+
+ /* Reset the DiskOnChip ASIC */
+ tmp = DOC_MODE_RESET | DOC_MODE_MDWREN | DOC_MODE_RST_LAT |
+ DOC_MODE_BDECT;
+ WriteDOC(tmp, window, Mplus_DOCControl);
+ WriteDOC(~tmp, window, Mplus_CtrlConfirm);
+
+ mdelay(1);
+ /* Enable the DiskOnChip ASIC */
+ tmp = DOC_MODE_NORMAL | DOC_MODE_MDWREN | DOC_MODE_RST_LAT |
+ DOC_MODE_BDECT;
+ WriteDOC(tmp, window, Mplus_DOCControl);
+ WriteDOC(~tmp, window, Mplus_CtrlConfirm);
+ mdelay(1);
+#endif /* !DOC_PASSIVE_PROBE */
+
+ ChipID = ReadDOC(window, ChipID);
+
+ switch (ChipID) {
+ case DOC_ChipID_DocMilPlus16:
+ case DOC_ChipID_DocMilPlus32:
+ /* Check the TOGGLE bit in the toggle register */
+ tmp = ReadDOC(window, Mplus_Toggle) & DOC_TOGGLE_BIT;
+ tmpb = ReadDOC(window, Mplus_Toggle) & DOC_TOGGLE_BIT;
+ tmpc = ReadDOC(window, Mplus_Toggle) & DOC_TOGGLE_BIT;
+ if (tmp != tmpb && tmp == tmpc)
+ return ChipID;
+ default:
+ break;
+ }
+ /* FALL TRHU */
+
+ default:
+
+#ifdef CONFIG_MTD_DOCPROBE_55AA
+ printk(KERN_DEBUG "Possible DiskOnChip with unknown ChipID %2.2X found at 0x%lx\n",
+ ChipID, physadr);
+#endif
+#ifndef DOC_PASSIVE_PROBE
+ /* Put back the contents of the DOCControl register, in case it's not
+ * actually a DiskOnChip.
+ */
+ WriteDOC(tmp2, window, DOCControl);
+#endif
+ return 0;
+ }
+
+ printk(KERN_WARNING "DiskOnChip failed TOGGLE test, dropping.\n");
+
+#ifndef DOC_PASSIVE_PROBE
+ /* Put back the contents of the DOCControl register: it's not a DiskOnChip */
+ WriteDOC(tmp2, window, DOCControl);
+#endif
+ return 0;
+}
+
+static int docfound;
+
+static void __init DoC_Probe(unsigned long physadr)
+{
+ void __iomem *docptr;
+ struct DiskOnChip *this;
+ struct mtd_info *mtd;
+ int ChipID;
+ char namebuf[15];
+ char *name = namebuf;
+ char *im_funcname = NULL;
+ char *im_modname = NULL;
+ void (*initroutine)(struct mtd_info *) = NULL;
+
+ docptr = ioremap(physadr, DOC_IOREMAP_LEN);
+
+ if (!docptr)
+ return;
+
+ if ((ChipID = doccheck(docptr, physadr))) {
+ if (ChipID == DOC_ChipID_Doc2kTSOP) {
+ /* Remove this at your own peril. The hardware driver works but nothing prevents you from erasing bad blocks */
+ printk(KERN_NOTICE "Refusing to drive DiskOnChip 2000 TSOP until Bad Block Table is correctly supported by INFTL\n");
+ iounmap(docptr);
+ return;
+ }
+ docfound = 1;
+ mtd = kmalloc(sizeof(struct DiskOnChip) + sizeof(struct mtd_info), GFP_KERNEL);
+
+ if (!mtd) {
+ printk(KERN_WARNING "Cannot allocate memory for data structures. Dropping.\n");
+ iounmap(docptr);
+ return;
+ }
+
+ this = (struct DiskOnChip *)(&mtd[1]);
+
+ memset((char *)mtd,0, sizeof(struct mtd_info));
+ memset((char *)this, 0, sizeof(struct DiskOnChip));
+
+ mtd->priv = this;
+ this->virtadr = docptr;
+ this->physadr = physadr;
+ this->ChipID = ChipID;
+ sprintf(namebuf, "with ChipID %2.2X", ChipID);
+
+ switch(ChipID) {
+ case DOC_ChipID_Doc2kTSOP:
+ name="2000 TSOP";
+ im_funcname = "DoC2k_init";
+ im_modname = "doc2000";
+ break;
+
+ case DOC_ChipID_Doc2k:
+ name="2000";
+ im_funcname = "DoC2k_init";
+ im_modname = "doc2000";
+ break;
+
+ case DOC_ChipID_DocMil:
+ name="Millennium";
+#ifdef DOC_SINGLE_DRIVER
+ im_funcname = "DoC2k_init";
+ im_modname = "doc2000";
+#else
+ im_funcname = "DoCMil_init";
+ im_modname = "doc2001";
+#endif /* DOC_SINGLE_DRIVER */
+ break;
+
+ case DOC_ChipID_DocMilPlus16:
+ case DOC_ChipID_DocMilPlus32:
+ name="MillenniumPlus";
+ im_funcname = "DoCMilPlus_init";
+ im_modname = "doc2001plus";
+ break;
+ }
+
+ if (im_funcname)
+ initroutine = inter_module_get_request(im_funcname, im_modname);
+
+ if (initroutine) {
+ (*initroutine)(mtd);
+ inter_module_put(im_funcname);
+ return;
+ }
+ printk(KERN_NOTICE "Cannot find driver for DiskOnChip %s at 0x%lX\n", name, physadr);
+ kfree(mtd);
+ }
+ iounmap(docptr);
+}
+
+
+/****************************************************************************
+ *
+ * Module stuff
+ *
+ ****************************************************************************/
+
+static int __init init_doc(void)
+{
+ int i;
+
+ if (doc_config_location) {
+ printk(KERN_INFO "Using configured DiskOnChip probe address 0x%lx\n", doc_config_location);
+ DoC_Probe(doc_config_location);
+ } else {
+ for (i=0; (doc_locations[i] != 0xffffffff); i++) {
+ DoC_Probe(doc_locations[i]);
+ }
+ }
+ /* No banner message any more. Print a message if no DiskOnChip
+ found, so the user knows we at least tried. */
+ if (!docfound)
+ printk(KERN_INFO "No recognised DiskOnChip devices found\n");
+ return -EAGAIN;
+}
+
+module_init(init_doc);
+
+MODULE_LICENSE("GPL");
+MODULE_AUTHOR("David Woodhouse <dwmw2@infradead.org>");
+MODULE_DESCRIPTION("Probe code for DiskOnChip 2000 and Millennium devices");
+