/* * linux/drivers/block/cmd640.c Version 1.02 Sep 01, 1996 * * Copyright (C) 1995-1996 Linus Torvalds & authors (see below) */ /* * Original author: abramov@cecmow.enet.dec.com (Igor Abramov) * * Maintained by: mlord@pobox.com (Mark Lord) * with fanatical support from a legion of hackers! * * This file provides support for the advanced features and bugs * of IDE interfaces using the CMD Technologies 0640 IDE interface chip. * * These chips are basically fucked by design, and getting this driver * to work on every motherboard design that uses this screwed chip seems * bloody well impossible. However, we're still trying. * * Version 0.97 worked for everybody. * * User feedback is essential. Many thanks to the beta test team: * * A.Hartgers@stud.tue.nl, JZDQC@CUNYVM.CUNY.edu, abramov@cecmow.enet.dec.com, * bardj@utopia.ppp.sn.no, bart@gaga.tue.nl, bbol001@cs.auckland.ac.nz, * chrisc@dbass.demon.co.uk, dalecki@namu26.Num.Math.Uni-Goettingen.de, * derekn@vw.ece.cmu.edu, florian@btp2x3.phy.uni-bayreuth.de, * flynn@dei.unipd.it, gadio@netvision.net.il, godzilla@futuris.net, * j@pobox.com, jkemp1@mises.uni-paderborn.de, jtoppe@hiwaay.net, * kerouac@ssnet.com, meskes@informatik.rwth-aachen.de, hzoli@cs.elte.hu, * peter@udgaard.isgtec.com, phil@tazenda.demon.co.uk, roadcapw@cfw.com, * s0033las@sun10.vsz.bme.hu, schaffer@tam.cornell.edu, sjd@slip.net, * steve@ei.org, ulrpeg@bigcomm.gun.de, ism@tardis.ed.ac.uk, mack@cray.com * liug@mama.indstate.edu, and others. * * Version 0.01 Initial version, hacked out of ide.c, * and #include'd rather than compiled separately. * This will get cleaned up in a subsequent release. * * Version 0.02 Fixes for vlb initialization code, enable prefetch * for versions 'B' and 'C' of chip by default, * some code cleanup. * * Version 0.03 Added reset of secondary interface, * and black list for devices which are not compatible * with prefetch mode. Separate function for setting * prefetch is added, possibly it will be called some * day from ioctl processing code. * * Version 0.04 Now configs/compiles separate from ide.c * * Version 0.05 Major rewrite of interface timing code. * Added new function cmd640_set_mode to set PIO mode * from ioctl call. New drives added to black list. * * Version 0.06 More code cleanup. Prefetch is enabled only for * detected hard drives, not included in prefetch * black list. * * Version 0.07 Changed to more conservative drive tuning policy. * Unknown drives, which report PIO < 4 are set to * (reported_PIO - 1) if it is supported, or to PIO0. * List of known drives extended by info provided by * CMD at their ftp site. * * Version 0.08 Added autotune/noautotune support. * * Version 0.09 Try to be smarter about 2nd port enabling. * Version 0.10 Be nice and don't reset 2nd port. * Version 0.11 Try to handle more wierd situations. * * Version 0.12 Lots of bug fixes from Laszlo Peter * irq unmasking disabled for reliability. * try to be even smarter about the second port. * tidy up source code formatting. * Version 0.13 permit irq unmasking again. * Version 0.90 massive code cleanup, some bugs fixed. * defaults all drives to PIO mode0, prefetch off. * autotune is OFF by default, with compile time flag. * prefetch can be turned OFF/ON using "hdparm -p8/-p9" * (requires hdparm-3.1 or newer) * Version 0.91 first release to linux-kernel list. * Version 0.92 move initial reg dump to separate callable function * change "readahead" to "prefetch" to avoid confusion * Version 0.95 respect original BIOS timings unless autotuning. * tons of code cleanup and rearrangement. * added CONFIG_BLK_DEV_CMD640_ENHANCED option * prevent use of unmask when prefetch is on * Version 0.96 prevent use of io_32bit when prefetch is off * Version 0.97 fix VLB secondary interface for sjd@slip.net * other minor tune-ups: 0.96 was very good. * Version 0.98 ignore PCI version when disabled by BIOS * Version 0.99 display setup/active/recovery clocks with PIO mode * Version 1.00 Mmm.. cannot depend on PCMD_ENA in all systems * Version 1.01 slow/fast devsel can be selected with "hdparm -p6/-p7" * ("fast" is necessary for 32bit I/O in some systems) * Version 1.02 fix bug that resulted in slow "setup times" * (patch courtesy of Zoltan Hidvegi) */ #undef REALLY_SLOW_IO /* most systems can safely undef this */ #define CMD640_PREFETCH_MASKS 1 #include #include #include #include #include #include #include #include #include #include #include "ide.h" #include "ide_modes.h" /* * This flag is set in ide.c by the parameter: ide0=cmd640_vlb */ int cmd640_vlb = 0; /* * CMD640 specific registers definition. */ #define VID 0x00 #define DID 0x02 #define PCMD 0x04 #define PCMD_ENA 0x01 #define PSTTS 0x06 #define REVID 0x08 #define PROGIF 0x09 #define SUBCL 0x0a #define BASCL 0x0b #define BaseA0 0x10 #define BaseA1 0x14 #define BaseA2 0x18 #define BaseA3 0x1c #define INTLINE 0x3c #define INPINE 0x3d #define CFR 0x50 #define CFR_DEVREV 0x03 #define CFR_IDE01INTR 0x04 #define CFR_DEVID 0x18 #define CFR_AT_VESA_078h 0x20 #define CFR_DSA1 0x40 #define CFR_DSA0 0x80 #define CNTRL 0x51 #define CNTRL_DIS_RA0 0x40 #define CNTRL_DIS_RA1 0x80 #define CNTRL_ENA_2ND 0x08 #define CMDTIM 0x52 #define ARTTIM0 0x53 #define DRWTIM0 0x54 #define ARTTIM1 0x55 #define DRWTIM1 0x56 #define ARTTIM23 0x57 #define ARTTIM23_DIS_RA2 0x04 #define ARTTIM23_DIS_RA3 0x08 #define DRWTIM23 0x58 #define BRST 0x59 /* * Registers and masks for easy access by drive index: */ static byte prefetch_regs[4] = {CNTRL, CNTRL, ARTTIM23, ARTTIM23}; static byte prefetch_masks[4] = {CNTRL_DIS_RA0, CNTRL_DIS_RA1, ARTTIM23_DIS_RA2, ARTTIM23_DIS_RA3}; #ifdef CONFIG_BLK_DEV_CMD640_ENHANCED static byte arttim_regs[4] = {ARTTIM0, ARTTIM1, ARTTIM23, ARTTIM23}; static byte drwtim_regs[4] = {DRWTIM0, DRWTIM1, DRWTIM23, DRWTIM23}; /* * Current cmd640 timing values for each drive. * The defaults for each are the slowest possible timings. */ static byte setup_counts[4] = {4, 4, 4, 4}; /* Address setup count (in clocks) */ static byte active_counts[4] = {16, 16, 16, 16}; /* Active count (encoded) */ static byte recovery_counts[4] = {16, 16, 16, 16}; /* Recovery count (encoded) */ #endif /* CONFIG_BLK_DEV_CMD640_ENHANCED */ /* * These are initialized to point at the devices we control */ static ide_hwif_t *cmd_hwif0, *cmd_hwif1; static ide_drive_t *cmd_drives[4]; /* * Interface to access cmd640x registers */ static unsigned int cmd640_key; static void (*put_cmd640_reg)(unsigned short reg, byte val); static byte (*get_cmd640_reg)(unsigned short reg); /* * This is read from the CFR reg, and is used in several places. */ static unsigned int cmd640_chip_version; /* * The CMD640x chip does not support DWORD config write cycles, but some * of the BIOSes use them to implement the config services. * Therefore, we must use direct IO instead. */ /* PCI method 1 access */ static void put_cmd640_reg_pci1 (unsigned short reg, byte val) { unsigned long flags; save_flags(flags); cli(); outl_p((reg & 0xfc) | cmd640_key, 0xcf8); outb_p(val, (reg & 3) | 0xcfc); restore_flags(flags); } static byte get_cmd640_reg_pci1 (unsigned short reg) { byte b; unsigned long flags; save_flags(flags); cli(); outl_p((reg & 0xfc) | cmd640_key, 0xcf8); b = inb_p((reg & 3) | 0xcfc); restore_flags(flags); return b; } /* PCI method 2 access (from CMD datasheet) */ static void put_cmd640_reg_pci2 (unsigned short reg, byte val) { unsigned long flags; save_flags(flags); cli(); outb_p(0x10, 0xcf8); outb_p(val, cmd640_key + reg); outb_p(0, 0xcf8); restore_flags(flags); } static byte get_cmd640_reg_pci2 (unsigned short reg) { byte b; unsigned long flags; save_flags(flags); cli(); outb_p(0x10, 0xcf8); b = inb_p(cmd640_key + reg); outb_p(0, 0xcf8); restore_flags(flags); return b; } /* VLB access */ static void put_cmd640_reg_vlb (unsigned short reg, byte val) { unsigned long flags; save_flags(flags); cli(); outb_p(reg, cmd640_key); outb_p(val, cmd640_key + 4); restore_flags(flags); } static byte get_cmd640_reg_vlb (unsigned short reg) { byte b; unsigned long flags; save_flags(flags); cli(); outb_p(reg, cmd640_key); b = inb_p(cmd640_key + 4); restore_flags(flags); return b; } static int match_pci_cmd640_device (void) { const byte ven_dev[4] = {0x95, 0x10, 0x40, 0x06}; unsigned int i; for (i = 0; i < 4; i++) { if (get_cmd640_reg(i) != ven_dev[i]) return 0; } #ifdef STUPIDLY_TRUST_BROKEN_PCMD_ENA_BIT if ((get_cmd640_reg(PCMD) & PCMD_ENA) == 0) { printk("ide: cmd640 on PCI disabled by BIOS\n"); return 0; } #endif /* STUPIDLY_TRUST_BROKEN_PCMD_ENA_BIT */ return 1; /* success */ } /* * Probe for CMD640x -- pci method 1 */ static int probe_for_cmd640_pci1 (void) { get_cmd640_reg = get_cmd640_reg_pci1; put_cmd640_reg = put_cmd640_reg_pci1; for (cmd640_key = 0x80000000; cmd640_key <= 0x8000f800; cmd640_key += 0x800) { if (match_pci_cmd640_device()) return 1; /* success */ } return 0; } /* * Probe for CMD640x -- pci method 2 */ static int probe_for_cmd640_pci2 (void) { get_cmd640_reg = get_cmd640_reg_pci2; put_cmd640_reg = put_cmd640_reg_pci2; for (cmd640_key = 0xc000; cmd640_key <= 0xcf00; cmd640_key += 0x100) { if (match_pci_cmd640_device()) return 1; /* success */ } return 0; } /* * Probe for CMD640x -- vlb */ static int probe_for_cmd640_vlb (void) { byte b; get_cmd640_reg = get_cmd640_reg_vlb; put_cmd640_reg = put_cmd640_reg_vlb; cmd640_key = 0x178; b = get_cmd640_reg(CFR); if (b == 0xff || b == 0x00 || (b & CFR_AT_VESA_078h)) { cmd640_key = 0x78; b = get_cmd640_reg(CFR); if (b == 0xff || b == 0x00 || !(b & CFR_AT_VESA_078h)) return 0; } return 1; /* success */ } /* * Returns 1 if an IDE interface/drive exists at 0x170, * Returns 0 otherwise. */ static int secondary_port_responding (void) { unsigned long flags; save_flags(flags); cli(); outb_p(0x0a, 0x170 + IDE_SELECT_OFFSET); /* select drive0 */ udelay(100); if ((inb_p(0x170 + IDE_SELECT_OFFSET) & 0x1f) != 0x0a) { outb_p(0x1a, 0x170 + IDE_SELECT_OFFSET); /* select drive1 */ udelay(100); if ((inb_p(0x170 + IDE_SELECT_OFFSET) & 0x1f) != 0x1a) { restore_flags(flags); return 0; /* nothing responded */ } } restore_flags(flags); return 1; /* success */ } #ifdef CMD640_DUMP_REGS /* * Dump out all cmd640 registers. May be called from ide.c */ void cmd640_dump_regs (void) { unsigned int reg = cmd640_vlb ? 0x50 : 0x00; /* Dump current state of chip registers */ printk("ide: cmd640 internal register dump:"); for (; reg <= 0x59; reg++) { if (!(reg & 0x0f)) printk("\n%04x:", reg); printk(" %02x", get_cmd640_reg(reg)); } printk("\n"); } #endif /* * Check whether prefetch is on for a drive, * and initialize the unmask flags for safe operation. */ static void check_prefetch (unsigned int index) { ide_drive_t *drive = cmd_drives[index]; byte b = get_cmd640_reg(prefetch_regs[index]); if (b & prefetch_masks[index]) { /* is prefetch off? */ drive->no_unmask = 0; drive->no_io_32bit = 1; drive->io_32bit = 0; } else { #if CMD640_PREFETCH_MASKS drive->no_unmask = 1; drive->unmask = 0; #endif drive->no_io_32bit = 0; } } /* * Figure out which devices we control */ static void setup_device_ptrs (void) { unsigned int i; cmd_hwif0 = &ide_hwifs[0]; /* default, if not found below */ cmd_hwif1 = &ide_hwifs[1]; /* default, if not found below */ for (i = 0; i < MAX_HWIFS; i++) { ide_hwif_t *hwif = &ide_hwifs[i]; if (hwif->chipset == ide_unknown || hwif->chipset == ide_generic) { if (hwif->io_ports[IDE_DATA_OFFSET] == 0x1f0) cmd_hwif0 = hwif; else if (hwif->io_ports[IDE_DATA_OFFSET] == 0x170) cmd_hwif1 = hwif; } } cmd_drives[0] = &cmd_hwif0->drives[0]; cmd_drives[1] = &cmd_hwif0->drives[1]; cmd_drives[2] = &cmd_hwif1->drives[0]; cmd_drives[3] = &cmd_hwif1->drives[1]; } #ifdef CONFIG_BLK_DEV_CMD640_ENHANCED /* * Sets prefetch mode for a drive. */ static void set_prefetch_mode (unsigned int index, int mode) { ide_drive_t *drive = cmd_drives[index]; int reg = prefetch_regs[index]; byte b; unsigned long flags; save_flags(flags); cli(); b = get_cmd640_reg(reg); if (mode) { /* want prefetch on? */ #if CMD640_PREFETCH_MASKS drive->no_unmask = 1; drive->unmask = 0; #endif drive->no_io_32bit = 0; b &= ~prefetch_masks[index]; /* enable prefetch */ } else { drive->no_unmask = 0; drive->no_io_32bit = 1; drive->io_32bit = 0; b |= prefetch_masks[index]; /* disable prefetch */ } put_cmd640_reg(reg, b); restore_flags(flags); } /* * Dump out current drive clocks settings */ static void display_clocks (unsigned int index) { byte active_count, recovery_count; active_count = active_counts[index]; if (active_count == 1) ++active_count; recovery_count = recovery_counts[index]; if (active_count > 3 && recovery_count == 1) ++recovery_count; if (cmd640_chip_version > 1) recovery_count += 1; /* cmd640b uses (count + 1)*/ printk(", clocks=%d/%d/%d\n", setup_counts[index], active_count, recovery_count); } /* * Pack active and recovery counts into single byte representation * used by controller */ inline static byte pack_nibbles (byte upper, byte lower) { return ((upper & 0x0f) << 4) | (lower & 0x0f); } /* * This routine retrieves the initial drive timings from the chipset. */ static void retrieve_drive_counts (unsigned int index) { byte b; /* * Get the internal setup timing, and convert to clock count */ b = get_cmd640_reg(arttim_regs[index]) & ~0x3f; switch (b) { case 0x00: b = 4; break; case 0x80: b = 3; break; case 0x40: b = 2; break; default: b = 5; break; } setup_counts[index] = b; /* * Get the active/recovery counts */ b = get_cmd640_reg(drwtim_regs[index]); active_counts[index] = (b >> 4) ? (b >> 4) : 0x10; recovery_counts[index] = (b & 0x0f) ? (b & 0x0f) : 0x10; } /* * This routine writes the prepared setup/active/recovery counts * for a drive into the cmd640 chipset registers to active them. */ static void program_drive_counts (unsigned int index) { unsigned long flags; byte setup_count = setup_counts[index]; byte active_count = active_counts[index]; byte recovery_count = recovery_counts[index]; /* * Set up address setup count and drive read/write timing registers. * Primary interface has individual count/timing registers for * each drive. Secondary interface has one common set of registers, * so we merge the timings, using the slowest value for each timing. */ if (index > 1) { unsigned int mate; if (cmd_drives[mate = index ^ 1]->present) { if (setup_count < setup_counts[mate]) setup_count = setup_counts[mate]; if (active_count < active_counts[mate]) active_count = active_counts[mate]; if (recovery_count < recovery_counts[mate]) recovery_count = recovery_counts[mate]; } } /* * Convert setup_count to internal chipset representation */ switch (setup_count) { case 4: setup_count = 0x00; break; case 3: setup_count = 0x80; break; case 1: case 2: setup_count = 0x40; break; default: setup_count = 0xc0; /* case 5 */ } /* * Now that everything is ready, program the new timings */ save_flags (flags); cli(); /* * Program the address_setup clocks into ARTTIM reg, * and then the active/recovery counts into the DRWTIM reg * (this converts counts of 16 into counts of zero -- okay). */ setup_count |= get_cmd640_reg(arttim_regs[index]) & 0x3f; put_cmd640_reg(arttim_regs[index], setup_count); put_cmd640_reg(drwtim_regs[index], pack_nibbles(active_count, recovery_count)); restore_flags(flags); } /* * Set a specific pio_mode for a drive */ static void cmd640_set_mode (unsigned int index, byte pio_mode, unsigned int cycle_time) { int setup_time, active_time, recovery_time, clock_time; byte setup_count, active_count, recovery_count, recovery_count2, cycle_count; int bus_speed = ide_system_bus_speed(); if (pio_mode > 5) pio_mode = 5; setup_time = ide_pio_timings[pio_mode].setup_time; active_time = ide_pio_timings[pio_mode].active_time; recovery_time = cycle_time - (setup_time + active_time); clock_time = 1000 / bus_speed; cycle_count = (cycle_time + clock_time - 1) / clock_time; setup_count = (setup_time + clock_time - 1) / clock_time; active_count = (active_time + clock_time - 1) / clock_time; if (active_count < 2) active_count = 2; /* minimum allowed by cmd640 */ recovery_count = (recovery_time + clock_time - 1) / clock_time; recovery_count2 = cycle_count - (setup_count + active_count); if (recovery_count2 > recovery_count) recovery_count = recovery_count2; if (recovery_count < 2) recovery_count = 2; /* minimum allowed by cmd640 */ if (recovery_count > 17) { active_count += recovery_count - 17; recovery_count = 17; } if (active_count > 16) active_count = 16; /* maximum allowed by cmd640 */ if (cmd640_chip_version > 1) recovery_count -= 1; /* cmd640b uses (count + 1)*/ if (recovery_count > 16) recovery_count = 16; /* maximum allowed by cmd640 */ setup_counts[index] = setup_count; active_counts[index] = active_count; recovery_counts[index] = recovery_count; /* * In a perfect world, we might set the drive pio mode here * (using WIN_SETFEATURE) before continuing. * * But we do not, because: * 1) this is the wrong place to do it (proper is do_special() in ide.c) * 2) in practice this is rarely, if ever, necessary */ program_drive_counts (index); } /* * Drive PIO mode selection: */ static void cmd640_tune_drive (ide_drive_t *drive, byte mode_wanted) { byte b; ide_pio_data_t d; unsigned int index = 0; while (drive != cmd_drives[index]) { if (++index > 3) { printk("%s: bad news in cmd640_tune_drive\n", drive->name); return; } } switch (mode_wanted) { case 6: /* set fast-devsel off */ case 7: /* set fast-devsel on */ mode_wanted &= 1; b = get_cmd640_reg(CNTRL) & ~0x27; if (mode_wanted) b |= 0x27; put_cmd640_reg(CNTRL, b); printk("%s: %sabled cmd640 fast host timing (devsel)\n", drive->name, mode_wanted ? "en" : "dis"); return; case 8: /* set prefetch off */ case 9: /* set prefetch on */ mode_wanted &= 1; set_prefetch_mode(index, mode_wanted); printk("%s: %sabled cmd640 prefetch\n", drive->name, mode_wanted ? "en" : "dis"); return; } (void) ide_get_best_pio_mode (drive, mode_wanted, 5, &d); cmd640_set_mode (index, d.pio_mode, d.cycle_time); printk ("%s: selected cmd640 PIO mode%d (%dns)%s", drive->name, d.pio_mode, d.cycle_time, d.overridden ? " (overriding vendor mode)" : ""); display_clocks(index); } #endif /* CONFIG_BLK_DEV_CMD640_ENHANCED */ /* * Probe for a cmd640 chipset, and initialize it if found. Called from ide.c */ int ide_probe_for_cmd640x (void) { #ifdef CONFIG_BLK_DEV_CMD640_ENHANCED int second_port_toggled = 0; #endif /* CONFIG_BLK_DEV_CMD640_ENHANCED */ int second_port_cmd640 = 0; const char *bus_type, *port2; unsigned int index; byte b, cfr; if (cmd640_vlb && probe_for_cmd640_vlb()) { bus_type = "VLB"; } else { cmd640_vlb = 0; if (probe_for_cmd640_pci1()) bus_type = "PCI (type1)"; else if (probe_for_cmd640_pci2()) bus_type = "PCI (type2)"; else return 0; } /* * Undocumented magic (there is no 0x5b reg in specs) */ put_cmd640_reg(0x5b, 0xbd); if (get_cmd640_reg(0x5b) != 0xbd) { printk("ide: cmd640 init failed: wrong value in reg 0x5b\n"); return 0; } put_cmd640_reg(0x5b, 0); #ifdef CMD640_DUMP_REGS CMD640_DUMP_REGS; #endif /* * Documented magic begins here */ cfr = get_cmd640_reg(CFR); cmd640_chip_version = cfr & CFR_DEVREV; if (cmd640_chip_version == 0) { printk ("ide: bad cmd640 revision: %d\n", cmd640_chip_version); return 0; } /* * Initialize data for primary port */ setup_device_ptrs (); printk("%s: buggy cmd640%c interface on %s, config=0x%02x\n", cmd_hwif0->name, 'a' + cmd640_chip_version - 1, bus_type, cfr); cmd_hwif0->chipset = ide_cmd640; #ifdef CONFIG_BLK_DEV_CMD640_ENHANCED cmd_hwif0->tuneproc = &cmd640_tune_drive; #endif /* CONFIG_BLK_DEV_CMD640_ENHANCED */ /* * Ensure compatibility by always using the slowest timings * for access to the drive's command register block, * and reset the prefetch burstsize to default (512 bytes). * * Maybe we need a way to NOT do these on *some* systems? */ put_cmd640_reg(CMDTIM, 0); put_cmd640_reg(BRST, 0x40); /* * Try to enable the secondary interface, if not already enabled */ if (cmd_hwif1->noprobe) { port2 = "not probed"; } else { b = get_cmd640_reg(CNTRL); if (secondary_port_responding()) { if ((b & CNTRL_ENA_2ND)) { second_port_cmd640 = 1; port2 = "okay"; } else if (cmd640_vlb) { second_port_cmd640 = 1; port2 = "alive"; } else port2 = "not cmd640"; } else { put_cmd640_reg(CNTRL, b ^ CNTRL_ENA_2ND); /* toggle the bit */ if (secondary_port_responding()) { second_port_cmd640 = 1; #ifdef CONFIG_BLK_DEV_CMD640_ENHANCED second_port_toggled = 1; #endif /* CONFIG_BLK_DEV_CMD640_ENHANCED */ port2 = "enabled"; } else { put_cmd640_reg(CNTRL, b); /* restore original setting */ port2 = "not responding"; } } } /* * Initialize data for secondary cmd640 port, if enabled */ if (second_port_cmd640) { cmd_hwif0->serialized = 1; cmd_hwif1->serialized = 1; cmd_hwif1->chipset = ide_cmd640; cmd_hwif0->mate = cmd_hwif1; cmd_hwif1->mate = cmd_hwif0; cmd_hwif1->channel = 1; #ifdef CONFIG_BLK_DEV_CMD640_ENHANCED cmd_hwif1->tuneproc = &cmd640_tune_drive; #endif /* CONFIG_BLK_DEV_CMD640_ENHANCED */ } printk("%s: %sserialized, secondary interface %s\n", cmd_hwif1->name, cmd_hwif0->serialized ? "" : "not ", port2); /* * Establish initial timings/prefetch for all drives. * Do not unnecessarily disturb any prior BIOS setup of these. */ for (index = 0; index < (2 + (second_port_cmd640 << 1)); index++) { ide_drive_t *drive = cmd_drives[index]; #ifdef CONFIG_BLK_DEV_CMD640_ENHANCED if (drive->autotune || ((index > 1) && second_port_toggled)) { /* * Reset timing to the slowest speed and turn off prefetch. * This way, the drive identify code has a better chance. */ setup_counts [index] = 4; /* max possible */ active_counts [index] = 16; /* max possible */ recovery_counts [index] = 16; /* max possible */ program_drive_counts (index); set_prefetch_mode (index, 0); printk("cmd640: drive%d timings/prefetch cleared\n", index); } else { /* * Record timings/prefetch without changing them. * This preserves any prior BIOS setup. */ retrieve_drive_counts (index); check_prefetch (index); printk("cmd640: drive%d timings/prefetch(%s) preserved", index, drive->no_io_32bit ? "off" : "on"); display_clocks(index); } #else /* * Set the drive unmask flags to match the prefetch setting */ check_prefetch (index); printk("cmd640: drive%d timings/prefetch(%s) preserved\n", index, drive->no_io_32bit ? "off" : "on"); #endif /* CONFIG_BLK_DEV_CMD640_ENHANCED */ } #ifdef CMD640_DUMP_REGS CMD640_DUMP_REGS; #endif return 1; }