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path: root/drivers/scsi/g_NCR5380.c
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2020-03-11scsi: docs: convert g_NCR5380.txt to ReSTMauro Carvalho Chehab
Link: https://lore.kernel.org/r/a66e9ea704be6a7aa81b9864ad66a32b75ab808d.1583136624.git.mchehab+huawei@kernel.org Acked-by: Finn Thain <fthain@telegraphics.com.au> Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org> Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2019-05-21treewide: Add SPDX license identifier for more missed filesThomas Gleixner
Add SPDX license identifiers to all files which: - Have no license information of any form - Have MODULE_LICENCE("GPL*") inside which was used in the initial scan/conversion to ignore the file These files fall under the project license, GPL v2 only. The resulting SPDX license identifier is: GPL-2.0-only Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-12-18scsi: remove the use_clustering flagChristoph Hellwig
The same effects can be achieved by setting the dma_boundary to PAGE_SIZE - 1 and the max_segment_size to PAGE_SIZE, so shift those settings into the drivers. Note that in many cases the setting might be bogus, but this keeps the status quo. [mkp: fix myrs and myrb] Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2017-08-25scsi: NCR5380: Move bus reset to host resetHannes Reinecke
The bus reset handler really is a host reset, so move it to eh_bus_reset_handler. Signed-off-by: Hannes Reinecke <hare@suse.com> Acked-by: Finn Thain <fthain@telegraphics.com.au> Reviewed-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Johannes Thumshirn <jthumshirn@suse.de> Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2017-08-24scsi: ncr5380: constify pnp_device_idArvind Yadav
pnp_device_id are not supposed to change at runtime. All functions working with pnp_device_id provided by <linux/pnp.h> work with const pnp_device_id. So mark the non-const structs as const. Signed-off-by: Arvind Yadav <arvind.yadav.cs@gmail.com> Acked-by: Finn Thain <fthain@telegraphics.com.au> Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2017-08-07scsi: g_NCR5380: Two DTC436 PDMA workaroundsOndrej Zary
Limit PDMA send to 512 B to avoid data corruption on DTC3181E. The corruption is always the same: one byte missing at the beginning of a 128 B block. It happens only with slow Quantum LPS 240 drive, not with faster IBM DORS-32160. It's not clear what causes this. Documentation for the DTC436 chip has not been made available. Signed-off-by: Finn Thain <fthain@telegraphics.com.au> Tested-by: Ondrej Zary <linux@rainbow-software.org> Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2017-08-07scsi: g_NCR5380: Re-work PDMA loopsOndrej Zary
The polling loops in pread() and pwrite() can easily become infinite loops and hang the machine. Merge the IRQ check into host buffer wait loop and add polling limit. Also place a limit on polling for 53C80 registers accessibility. [Use NCR5380_poll_politely2() for register polling. Rely on polling for gated IRQ rather than polling for phase error, like the algorithm in the 53c400 datasheet. Move DTC436 workarounds into a separate patch. Factor-out common code as wait_for_53c80_access(). Rework the residual calculations. -- F.T.] Signed-off-by: Ondrej Zary <linux@rainbow-software.org> Signed-off-by: Finn Thain <fthain@telegraphics.com.au> Tested-by: Ondrej Zary <linux@rainbow-software.org> Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2017-08-07scsi: g_NCR5380: Use unambiguous terminology for PDMA send and receiveFinn Thain
The word "read" may be used to mean "DMA read operation" or "SCSI READ command", though a READ command implies writing to memory. Signed-off-by: Finn Thain <fthain@telegraphics.com.au> Tested-by: Ondrej Zary <linux@rainbow-software.org> Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2017-08-07scsi: g_NCR5380: Cleanup comments and whitespaceFinn Thain
Signed-off-by: Finn Thain <fthain@telegraphics.com.au> Tested-by: Ondrej Zary <linux@rainbow-software.org> Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2017-08-07scsi: g_NCR5380: End PDMA transfer correctly on target disconnectionOndrej Zary
When an IRQ arrives during PDMA transfer, pread() and pwrite() return without waiting for the 53C80 registers to be ready and this ends up messing up the chip state. This was observed with SONY CDU-55S which is slow enough to disconnect during 4096-byte reads. IRQ during PDMA is not an error so don't return -1. Instead, store the remaining byte count for use by NCR5380_dma_residual(). [Poll for the BASR_END_DMA_TRANSFER condition rather than remove the error message -- F.T.] Signed-off-by: Ondrej Zary <linux@rainbow-software.org> Signed-off-by: Finn Thain <fthain@telegraphics.com.au> Tested-by: Ondrej Zary <linux@rainbow-software.org> Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2017-08-07scsi: g_NCR5380: Fix PDMA transfer sizeOndrej Zary
generic_NCR5380_dma_xfer_len() incorrectly uses cmd->transfersize which causes rescan-scsi-bus and CD-ROM access to hang the system. Use cmd->SCp.this_residual instead, like other NCR5380 drivers. Signed-off-by: Ondrej Zary <linux@rainbow-software.org> Signed-off-by: Finn Thain <fthain@telegraphics.com.au> Tested-by: Ondrej Zary <linux@rainbow-software.org> Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2017-04-20Annotate hardware config module parameters in drivers/scsi/David Howells
When the kernel is running in secure boot mode, we lock down the kernel to prevent userspace from modifying the running kernel image. Whilst this includes prohibiting access to things like /dev/mem, it must also prevent access by means of configuring driver modules in such a way as to cause a device to access or modify the kernel image. To this end, annotate module_param* statements that refer to hardware configuration and indicate for future reference what type of parameter they specify. The parameter parser in the core sees this information and can skip such parameters with an error message if the kernel is locked down. The module initialisation then runs as normal, but just sees whatever the default values for those parameters is. Note that we do still need to do the module initialisation because some drivers have viable defaults set in case parameters aren't specified and some drivers support automatic configuration (e.g. PNP or PCI) in addition to manually coded parameters. This patch annotates drivers in drivers/scsi/. Suggested-by: Alan Cox <gnomes@lxorguk.ukuu.org.uk> Signed-off-by: David Howells <dhowells@redhat.com> cc: "Juergen E. Fischer" <fischer@norbit.de> cc: "James E.J. Bottomley" <jejb@linux.vnet.ibm.com> cc: "Martin K. Petersen" <martin.petersen@oracle.com> cc: Dario Ballabio <ballabio_dario@emc.com> cc: Finn Thain <fthain@telegraphics.com.au> cc: Michael Schmitz <schmitzmic@gmail.com> cc: Achim Leubner <achim_leubner@adaptec.com> cc: linux-scsi@vger.kernel.org
2017-01-31scsi: ncr5380: Reduce #include filesFinn Thain
The NCR5380 wrapper drivers don't export symbols or declarations and don't actually need separate header files. Most of these header files were removed already; only sun3_scsi.h and g_NCR5380.h remain. Move the remaining definitions to the corresponding .c files to improve readability and proximity. The #defines which influence the #included core driver are no longer mixed up with unrelated #defines and #includes. Signed-off-by: Finn Thain <fthain@telegraphics.com.au> Tested-by: Ondrej Zary <linux@rainbow-software.org> Tested-by: Michael Schmitz <schmitzmic@gmail.com> Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2016-12-08scsi: g_NCR5380: Autoprobe board IRQ by defaultFinn Thain
Automatically probe the board irq when no irq parameter is provided, to simulate PnP. The old default behaviour was to disable the irq. Update driver documentation accordingly and add some printk messages to make this behaviour visible. Signed-off-by: Finn Thain <fthain@telegraphics.com.au> Tested-by: Ondrej Zary <linux@rainbow-software.org> Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2016-12-08scsi: g_NCR5380: Fix automatic IRQ on HP C2502 cardsFinn Thain
When IRQ_AUTO is used, the interrupt for HP C2502 cards gets disabled. Fix this by programming the card for a suitable free irq. The code for the free irq search comes from ALSA. Also allow IRQ 9 to work (it aliases to IRQ 2 on the card), as per Ondrej Zary's patch. Suggested-by: Ondrej Zary <linux@rainbow-software.org> Signed-off-by: Finn Thain <fthain@telegraphics.com.au> Tested-by: Ondrej Zary <linux@rainbow-software.org> Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2016-12-08scsi: g_NCR5380: Use probe_irq_*() for IRQ probingOndrej Zary
Use standard probe_irq_on() and probe_irq_off() functions instead of own implementation. This prevents warning messages like this in the kernel log: genirq: Flags mismatch irq 1. 00000000 (NCR-probe) vs. 00000080 (i8042) Move the IRQ trigger code from NCR5380 to g_NCR5380 where it is used. Also clear interrupt flag before and after the probe. Signed-off-by: Ondrej Zary <linux@rainbow-software.org> Signed-off-by: Finn Thain <fthain@telegraphics.com.au> Tested-by: Ondrej Zary <linux@rainbow-software.org> Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2016-12-08scsi: g_NCR5380: Check for chip presence before calling NCR5380_init()Ondrej Zary
Write and read back mode register to check that a chip is really there. If no card is present, reads result in 0xff. Signed-off-by: Ondrej Zary <linux@rainbow-software.org> Signed-off-by: Finn Thain <fthain@telegraphics.com.au> Tested-by: Ondrej Zary <linux@rainbow-software.org> Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2016-11-12scsi: g_NCR5380: Fix release_region in error handlingOndrej Zary
When a SW-configurable card is specified but not found, the driver releases wrong region, causing the following message in kernel log: Trying to free nonexistent resource <0000000000000000-000000000000000f> Fix it by assigning base earlier. Signed-off-by: Ondrej Zary <linux@rainbow-software.org> Fixes: a8cfbcaec0c1 ("scsi: g_NCR5380: Stop using scsi_module.c") Signed-off-by: Finn Thain <fthain@telegraphics.com.au> Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2016-11-08scsi: ncr5380: Use correct types for DMA routinesFinn Thain
Apply prototypes to get consistent function signatures for the DMA functions implemented in the board-specific drivers. To avoid using macros to alter actual parameters, some of those functions are reworked slightly. This is a step toward the goal of passing the board-specific routines to the core driver using an ops struct (as in a platform driver or library module). This also helps fix some inconsistent types: where the core driver uses ints (cmd->SCp.this_residual and hostdata->dma_len) for keeping track of transfers, certain board-specific routines used unsigned long. While we are fixing these function signatures, pass the hostdata pointer to DMA routines instead of a Scsi_Host pointer, for shorter and faster code. Signed-off-by: Finn Thain <fthain@telegraphics.com.au> Reviewed-by: Hannes Reinecke <hare@suse.com> Tested-by: Ondrej Zary <linux@rainbow-software.org> Tested-by: Michael Schmitz <schmitzmic@gmail.com> Acked-by: Russell King <rmk+kernel@armlinux.org.uk> Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2016-11-08scsi: ncr5380: Store IO ports and addresses in host private dataFinn Thain
The various 5380 drivers inconsistently store register pointers either in the Scsi_Host struct "legacy crap" area or in special, board-specific members of the NCR5380_hostdata struct. Uniform use of the latter struct makes for simpler and faster code (see the following patches) and helps to reduce use of the NCR5380_implementation_fields macro. Signed-off-by: Finn Thain <fthain@telegraphics.com.au> Reviewed-by: Hannes Reinecke <hare@suse.com> Tested-by: Ondrej Zary <linux@rainbow-software.org> Tested-by: Michael Schmitz <schmitzmic@gmail.com> Acked-by: Russell King <rmk+kernel@armlinux.org.uk> Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2016-11-08scsi: g_NCR5380: Merge g_NCR5380 and g_NCR5380_mmio driversOndrej Zary
Merge the port-mapped IO and memory-mapped IO support (with the help of ioport_map) into the g_NCR5380 module and delete g_NCR5380_mmio. Signed-off-by: Ondrej Zary <linux@rainbow-software.org> Signed-off-by: Finn Thain <fthain@telegraphics.com.au> Reviewed-by: Hannes Reinecke <hare@suse.com> Tested-by: Ondrej Zary <linux@rainbow-software.org> Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2016-09-29scsi: g_NCR5380: Stop using scsi_module.cOndrej Zary
Convert g_NCR5380 to use scsi_add_host instead of scsi_module.c Use pnp_driver and isa_driver to manage cards. In order to support multiple cards, new module parameter format is introduced. The old parameters are kept for compatibility. Signed-off-by: Ondrej Zary <linux@rainbow-software.org> Acked-by: Finn Thain <fthain@telegraphics.com.au> Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2016-09-29scsi: g_NCR5380: Reduce overrides[] from array to structOndrej Zary
Remove compile-time card type definition GENERIC_NCR5380_OVERRIDE. Then remove all code iterating the overrides[] array and reduce it to struct card. Signed-off-by: Ondrej Zary <linux@rainbow-software.org> Acked-by: Finn Thain <fthain@telegraphics.com.au> Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2016-09-29scsi: g_NCR5380: Remove deprecated __setupOndrej Zary
Remove deprecated __setup for parsing command line parameters. g_NCR5380.* parameters could be used instead. This might break existing setups with g_NCR5380 built-in (if there are any). But it has to go in order to remove the overrides[] array. Signed-off-by: Ondrej Zary <linux@rainbow-software.org> Acked-by: Finn Thain <fthain@telegraphics.com.au> Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2016-04-11ncr5380: Update usage documentationFinn Thain
Update kernel parameter documentation for atari_scsi, mac_scsi and g_NCR5380 drivers. Remove duplication. Signed-off-by: Finn Thain <fthain@telegraphics.com.au> Reviewed-by: Hannes Reinecke <hare@suse.com> Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2016-04-11ncr5380: Remove DONT_USE_INTR and AUTOPROBE_IRQ macrosFinn Thain
Signed-off-by: Finn Thain <fthain@telegraphics.com.au> Reviewed-by: Hannes Reinecke <hare@suse.com> Tested-by: Michael Schmitz <schmitzmic@gmail.com> Tested-by: Ondrej Zary <linux@rainbow-software.org> Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2016-04-11ncr5380: Merge DMA implementation from atari_NCR5380 core driverFinn Thain
Adopt the DMA implementation from atari_NCR5380.c. This means that atari_scsi and sun3_scsi can make use of the NCR5380.c core driver and the atari_NCR5380.c driver fork can be made redundant. Signed-off-by: Finn Thain <fthain@telegraphics.com.au> Reviewed-by: Hannes Reinecke <hare@suse.com> Tested-by: Michael Schmitz <schmitzmic@gmail.com> Tested-by: Ondrej Zary <linux@rainbow-software.org> Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2016-04-11ncr5380: Use DMA hooks for PDMAFinn Thain
Those wrapper drivers which use DMA define the REAL_DMA macro and those which use pseudo DMA define PSEUDO_DMA. These macros need to be removed for a number of reasons, not least of which is to have drivers share more code. Redefine the PDMA send and receive hooks as DMA setup hooks, so that the DMA code can be shared by all 5380 wrapper drivers. This will help to reunify the forked core driver. Signed-off-by: Finn Thain <fthain@telegraphics.com.au> Reviewed-by: Hannes Reinecke <hare@suse.com> Tested-by: Michael Schmitz <schmitzmic@gmail.com> Tested-by: Ondrej Zary <linux@rainbow-software.org> Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2016-04-11ncr5380: Remove PSEUDO_DMA macroFinn Thain
For those wrapper drivers which only implement Programmed IO, have NCR5380_dma_xfer_len() evaluate to zero. That allows PDMA to be easily disabled at run-time and so the PSEUDO_DMA macro is no longer needed. Also remove the spin counters used for debugging pseudo DMA drivers. Signed-off-by: Finn Thain <fthain@telegraphics.com.au> Reviewed-by: Hannes Reinecke <hare@suse.com> Tested-by: Michael Schmitz <schmitzmic@gmail.com> Tested-by: Ondrej Zary <linux@rainbow-software.org> Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2016-04-11ncr5380: Disable the DMA errata workaround flag by defaultFinn Thain
The only chip that needs the workarounds enabled is an early NMOS device. That means that the common case is to disable them. Unfortunately the sense of the flag is such that it has to be set for the common case. Rename the flag so that zero can be used to mean "no errata workarounds needed". This simplifies the code. Signed-off-by: Finn Thain <fthain@telegraphics.com.au> Reviewed-by: Hannes Reinecke <hare@suse.com> Tested-by: Michael Schmitz <schmitzmic@gmail.com> Tested-by: Ondrej Zary <linux@rainbow-software.org> Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2016-04-11ncr5380: Remove FLAG_NO_PSEUDO_DMA where possibleFinn Thain
Drivers that define PSEUDO_DMA also define NCR5380_dma_xfer_len. The core driver must call NCR5380_dma_xfer_len which means FLAG_NO_PSEUDO_DMA can be eradicated from the core driver. dmx3191d doesn't define PSEUDO_DMA and has no use for FLAG_NO_PSEUDO_DMA, so remove it there also. Signed-off-by: Finn Thain <fthain@telegraphics.com.au> Reviewed-by: Hannes Reinecke <hare@suse.com> Tested-by: Michael Schmitz <schmitzmic@gmail.com> Tested-by: Ondrej Zary <linux@rainbow-software.org> Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2016-04-11g_ncr5380: Remove CONFIG_SCSI_GENERIC_NCR53C400Finn Thain
This change brings a number of improvements: fewer macros, better test coverage, simpler code and sane Kconfig options. The downside is a small chance of incompatibility (which seems unavoidable). CONFIG_SCSI_GENERIC_NCR53C400 exists to enable or inhibit pseudo DMA transfers when the driver is used with 53C400-compatible cards. Thanks to Ondrej Zary's patches, PDMA now works which means it can be enabled unconditionally. Due to bad design, CONFIG_SCSI_GENERIC_NCR53C400 ties together unrelated functionality as it sets both PSEUDO_DMA and BIOSPARAM macros. This patch effectively enables PSEUDO_DMA and disables BIOSPARAM. The defconfigs and the Kconfig default leave CONFIG_SCSI_GENERIC_NCR53C400 undefined. Red Hat 9 and CentOS 2.1 were the same. This leaves both PSEUDO_DMA and BIOSPARAM disabled. The effect of this patch should be better performance from enabling PSEUDO_DMA. On the other hand, Debian 4 and SLES 10 had CONFIG_SCSI_GENERIC_NCR53C400 enabled, so both PSEUDO_DMA and BIOSPARAM were enabled. This patch might affect configurations like this by disabling BIOSPARAM. My best guess is that this could be a problem only in the vanishingly rare case that 1) the CHS values stored in the boot device partition table are wrong and 2) a 5380 card is in use (because PDMA on 53C400 used to be broken). Signed-off-by: Finn Thain <fthain@telegraphics.com.au> Reviewed-by: Hannes Reinecke <hare@suse.com> Tested-by: Ondrej Zary <linux@rainbow-software.org> Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2016-01-06ncr5380: Add support for HP C2502Ondrej Zary
HP C2502 cards (based on 53C400A chips) use different magic numbers for software-based I/O address configuration than other cards. The configuration is also extended to allow setting the IRQ. Move the configuration to a new function magic_configure() and move magic the magic numbers into an array. Add new magic numbers for these HP cards and hp_c2502 module parameter to use them, e.g.: modprobe g_NCR5380 ncr_irq=7 ncr_addr=0x280 hp_c2502=1 Tested with HP C2502 and DTCT-436P. Signed-off-by: Ondrej Zary <linux@rainbow-software.org> Signed-off-by: Finn Thain <fthain@telegraphics.com.au> Reviewed-by: Hannes Reinecke <hare@suse.com> Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2016-01-06ncr5380: Fix wait for 53C80 registers registers after PDMAOndrej Zary
The check for 53C80 registers accessibility was commented out because it was broken (inverted). Fix and enable it. Signed-off-by: Ondrej Zary <linux@rainbow-software.org> Signed-off-by: Finn Thain <fthain@telegraphics.com.au> Reviewed-by: Hannes Reinecke <hare@suse.com> Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2016-01-06ncr5380: Enable PDMA for DTC chipsOndrej Zary
Add I/O register mapping for DTC chips and enable PDMA mode. These chips have 16-bit wide HOST BUFFER register and it must be read by 16-bit accesses (we lose data otherwise). Large PIO transfers crash at least the DTCT-436P chip (all reads result in 0xFF) so this patch actually makes it work. The chip also crashes when we bang on the C400 host status register too heavily after PDMA write - a small udelay is needed. Tested on DTCT-436P and verified that it does not break 53C400A. Signed-off-by: Ondrej Zary <linux@rainbow-software.org> Signed-off-by: Finn Thain <fthain@telegraphics.com.au> Reviewed-by: Hannes Reinecke <hare@suse.com> Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2016-01-06ncr5380: Enable PDMA for NCR53C400AOndrej Zary
Add I/O register mapping for NCR53C400A and enable PDMA mode to improve performance and fix non-working IRQ. Tested with HP C2502 (and user-space enabler). Signed-off-by: Ondrej Zary <linux@rainbow-software.org> Signed-off-by: Finn Thain <fthain@telegraphics.com.au> Reviewed-by: Hannes Reinecke <hare@suse.com> Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2016-01-06ncr5380: Use runtime register mappingOndrej Zary
Convert compile-time C400_ register mapping to runtime mapping. This removes the weird negative register offsets and allows adding additional mappings. While at it, convert read/write loops into insb/outsb. Signed-off-by: Ondrej Zary <linux@rainbow-software.org> Signed-off-by: Finn Thain <fthain@telegraphics.com.au> Reviewed-by: Hannes Reinecke <hare@suse.com> Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2016-01-06ncr5380: Fix pseudo DMA transfers on 53C400Ondrej Zary
Pseudo-DMA (PDMA) has been broken for ages, resulting in hangs on 53C400-based cards. According to 53C400 datasheet, PDMA transfer length must be a multiple of 128. Check if that's true and use PIO if it's not. This makes PDMA work on 53C400 (Canon FG2-5202). Signed-off-by: Ondrej Zary <linux@rainbow-software.org> Signed-off-by: Finn Thain <fthain@telegraphics.com.au> Reviewed-by: Hannes Reinecke <hare@suse.com> Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2016-01-06ncr5380: Fix soft lockupsFinn Thain
Because of the rudimentary design of the chip, it is necessary to poll the SCSI bus signals during PIO and this tends to hog the CPU. The driver will accept new commands while others execute, and this causes a soft lockup because the workqueue item will not terminate until the issue queue is emptied. When exercising dmx3191d using sequential IO from dd, the driver is sent 512 KiB WRITE commands and 128 KiB READs. For a PIO transfer, the rate is is only about 300 KiB/s, so these are long-running commands. And although PDMA may run at several MiB/s, interrupts are disabled for the duration of the transfer. Fix the unresponsiveness and soft lockup issues by calling cond_resched() after each command is completed and by limiting max_sectors for drivers that don't implement real DMA. Signed-off-by: Finn Thain <fthain@telegraphics.com.au> Reviewed-by: Hannes Reinecke <hare@suse.com> Tested-by: Ondrej Zary <linux@rainbow-software.org> Tested-by: Michael Schmitz <schmitzmic@gmail.com> Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2016-01-06ncr5380: Use standard list data structureFinn Thain
The NCR5380 drivers have a home-spun linked list implementation for scsi_cmnd structs that uses cmd->host_scribble as a 'next' pointer. Adopt the standard list_head data structure and list operations instead. Remove the eh_abort_handler rather than convert it. Doing the conversion would only be churn because the existing EH handlers don't work and get replaced in a subsequent patch. Signed-off-by: Finn Thain <fthain@telegraphics.com.au> Reviewed-by: Hannes Reinecke <hare@suse.com> Tested-by: Ondrej Zary <linux@rainbow-software.org> Tested-by: Michael Schmitz <schmitzmic@gmail.com> Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2016-01-06ncr5380: Remove command list debug codeFinn Thain
Some NCR5380 hosts offer a .show_info method to access the contents of the various command list data structures from a procfs file. When NDEBUG is set, the same information is sent to the console during EH. The two core drivers, atari_NCR5380.c and NCR5380.c differ here. Because it is just for debugging, the easiest way to fix the discrepancy is simply remove this code. The only remaining users of NCR5380_show_info() and NCR5380_write_info() are drivers that define PSEUDO_DMA. The others have no use for the .show_info method, so don't initialize it. Signed-off-by: Finn Thain <fthain@telegraphics.com.au> Reviewed-by: Hannes Reinecke <hare@suse.com> Tested-by: Ondrej Zary <linux@rainbow-software.org> Tested-by: Michael Schmitz <schmitzmic@gmail.com> Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2016-01-06ncr5380: Remove redundant ICR_ARBITRATION_LOST test and eliminate FLAG_DTC3181EFinn Thain
Remove FLAG_DTC3181E. It was used to suppress a final Arbitration Lost (SEL asserted) test that isn't actually needed. The test was suppressed because it causes problems for DTC436 and DTC536 chips. It takes place after the host wins arbitration, so SEL has been asserted. These chips can't seem to tell whether it was the host or another bus device that did so. This questionable final test appears in a flow chart in an early NCR5380 datasheet. It was removed from later documents like the DP5380 datasheet. By the time this final test takes place, the driver has already tested the Arbitration Lost bit several times. The first test happens 3 us after BUS FREE (or longer due to register access delays). The protocol requires that a device stop signalling within 1.8 us after BUS FREE unless it won arbitration, in which case it must assert SEL, which is detected 1.2 us later by the first Arbitration Lost test. Signed-off-by: Finn Thain <fthain@telegraphics.com.au> Reviewed-by: Hannes Reinecke <hare@suse.com> Tested-by: Ondrej Zary <linux@rainbow-software.org> Tested-by: Michael Schmitz <schmitzmic@gmail.com> Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2016-01-06ncr5380: Fix and cleanup scsi_host_template initializersFinn Thain
Add missing .module initializer. Use distinct .proc_name values for the g_NCR5380 and g_NCR5380_mmio modules. Remove pointless CAN_QUEUE and CMD_PER_LUN override macros. Cleanup whitespace and code style. Signed-off-by: Finn Thain <fthain@telegraphics.com.au> Reviewed-by: Hannes Reinecke <hare@suse.com> Tested-by: Ondrej Zary <linux@rainbow-software.org> Tested-by: Michael Schmitz <schmitzmic@gmail.com> Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2016-01-06ncr5380: Cleanup #include directivesFinn Thain
Remove unused includes (stat.h, signal.h, proc_fs.h) and move includes needed by the core drivers into the common header (delay.h etc). Signed-off-by: Finn Thain <fthain@telegraphics.com.au> Reviewed-by: Hannes Reinecke <hare@suse.com> Tested-by: Ondrej Zary <linux@rainbow-software.org> Tested-by: Michael Schmitz <schmitzmic@gmail.com> Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2016-01-06ncr5380: Replace redundant flags with FLAG_NO_DMA_FIXUPFinn Thain
The flags DMA_WORKS_RIGHT, FLAG_NCR53C400 and FLAG_HAS_LAST_BYTE_SENT all mean the same thing, i.e. the chip is not a 538[01]. (More recent devices such as the 53C80 have a 'Last Byte Sent' bit in the Target Command Register as well as other fixes for End-of-DMA errata.) These flags have no additional meanings since previous cleanup patches eliminated the NCR53C400 macro, moved g_NCR5380-specific code out of the core driver and standardized interrupt handling. Use the FLAG_NO_DMA_FIXUP flag to suppress End-of-DMA errata workarounds, for those cards and drivers that make use of the TCR_LAST_BYTE_SENT bit. Remove the old flags. Signed-off-by: Finn Thain <fthain@telegraphics.com.au> Reviewed-by: Hannes Reinecke <hare@suse.com> Tested-by: Ondrej Zary <linux@rainbow-software.org> Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2016-01-06ncr5380: Standardize interrupt handlingFinn Thain
Because interrupt handling is crucial to the core driver(s), all wrapper drivers need to agree on this code. This patch removes discrepancies. NCR5380_intr() in NCR5380.c has the following pointless loop that differs from the code in atari_NCR5380.c. done = 1; do { /* ... */ } while (!done); The 'done' flag gets cleared when a reconnected command is to be processed from the work queue. But in NCR5380.c, the flag is also used to cause the interrupt conditions to be re-examined. Perhaps this was because NCR5380_reselect() was expected to cause another interrupt, or perhaps the remaining present interrupt conditions need to be handled after the NCR5380_reselect() call? Actually, both possibilities are bogus, as is the loop itself. It seems have been overlooked in the hit-and-miss removal of scsi host instance list iteration many years ago; see history/history.git commit 491447e1fcff ("[PATCH] next NCR5380 updates") and commit 69e1a9482e57 ("[PATCH] fix up NCR5380 private data"). See also my earlier patch, "Always retry arbitration and selection". The datasheet says, "IRQ can be reset simply by reading the Reset Parity/Interrupt Register". So don't treat the chip IRQ like a level-triggered interrupt. Of the conditions that set the IRQ flag, some are level-triggered and some are edge-triggered, which means IRQ itself must be edge-triggered. Some interrupt conditions are latched and some are not. Before clearing the chip IRQ flag, clear all state that may cause it to be raised. That means clearing the DMA Mode and Busy Monitor bits in the Mode Register and clearing the host ID in the Select Enable register. Also clean up some printk's and some comments. Keep atari_NCR5380.c and NCR5380.c in agreement. Signed-off-by: Finn Thain <fthain@telegraphics.com.au> Reviewed-by: Hannes Reinecke <hare@suse.com> Tested-by: Ondrej Zary <linux@rainbow-software.org> Tested-by: Michael Schmitz <schmitzmic@gmail.com> Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2016-01-06ncr5380: Rework disconnect versus poll logicFinn Thain
The atari_NCR5380.c and NCR5380.c core drivers differ in their handling of target disconnection. This is partly because atari_NCR5380.c had all of the polling and sleeping removed to become entirely interrupt-driven, and it is partly because of damage done to NCR5380.c after atari_NCR5380.c was forked. See commit 37cd23b44929 ("Linux 2.1.105") in history/history.git. The polling changes that were made in v2.1.105 are questionable at best: if REQ is not already asserted when NCR5380_transfer_pio() is invoked, and if the expected phase is DATA IN or DATA OUT, the function will schedule main() to execute after USLEEP_SLEEP jiffies and then return. The problems here are the expected REQ timing and the sleep interval*. Avoid this issue by using NCR5380_poll_politely() instead of scheduling main(). The atari_NCR5380.c core driver requires the use of the chip interrupt and always permits target disconnection. It sets the cmd->device->disconnect flag when a device disconnects, but never tests this flag. The NCR5380.c core driver permits disconnection only when instance->irq != NO_IRQ. It sets the cmd->device->disconnect flag when a device disconnects and it tests this flag in a couple of places: 1. During NCR5380_information_transfer(), following COMMAND OUT phase, if !cmd->device->disconnect, the initiator will take a guess as to whether or not the target will then choose to go to MESSAGE IN phase and disconnect. If the driver guesses "yes", it will schedule main() to execute after USLEEP_SLEEP jiffies and then return there. Unfortunately the driver may guess "yes" even after it has denied the target the disconnection privilege. When the target does not disconnect, the sleep can be beneficial, assuming the sleep interval is appropriate (mostly it is not*). And even if the driver guesses "yes" correctly, and the target would then disconnect, the driver still has to go through the MESSAGE IN phase in order to get to BUS FREE phase. The main loop can do nothing useful until BUS FREE, and sleeping just delays the phase transition. 2. If !cmd->device->disconnect and REQ is not already asserted when NCR5380_information_transfer() is invoked, the function polls for REQ for USLEEP_POLL jiffies. If REQ is not asserted, it then schedules main() to execute after USLEEP_SLEEP jiffies and returns. The idea is apparently to yeild the CPU while waiting for REQ. This is conditional upon !cmd->device->disconnect, but there seems to be no rhyme or reason for that. For example, the flag may be unset because disconnection privilege was denied because the driver has no IRQ. Or the flag may be unset because the device has never needed to disconnect before. Or if the flag is set, disconnection may have no relevance to the present bus phase. Another deficiency of the existing algorithm is as follows. When the driver has no IRQ, it prevents disconnection, and generally polls and sleeps more than it would normally. Now, if the driver is going to poll anyway, why not allow the target to disconnect? That way the driver can do something useful with the bus instead of polling unproductively! Avoid this pointless latency, complexity and guesswork by using NCR5380_poll_politely() instead of scheduling main(). * For g_NCR5380, the time intervals for USLEEP_SLEEP and USLEEP_POLL are 200 ms and 10 ms, respectively. They are 20 ms and 200 ms respectively for the other NCR5380 drivers. There doesn't seem to be any reason for this discrepancy. The timing seems to have no relation to the type of adapter. Bizarrely, the timing in g_NCR5380 seems to relate only to one particular type of target device. This patch attempts to solve the problem for all NCR5380 drivers and all target devices. Signed-off-by: Finn Thain <fthain@telegraphics.com.au> Reviewed-by: Hannes Reinecke <hare@suse.com> Tested-by: Ondrej Zary <linux@rainbow-software.org> Tested-by: Michael Schmitz <schmitzmic@gmail.com> Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2016-01-06ncr5380: Implement NCR5380_dma_xfer_len and remove LIMIT_TRANSFERSIZE macroFinn Thain
Follow the example of the atari_NCR5380.c core driver and adopt the NCR5380_dma_xfer_len() hook. Implement NCR5380_dma_xfer_len() for dtc.c and g_NCR5380.c to take care of the limitations of these cards. Keep the default for drivers using PSEUDO_DMA. Eliminate the unused macro LIMIT_TRANSFERSIZE. Signed-off-by: Finn Thain <fthain@telegraphics.com.au> Reviewed-by: Hannes Reinecke <hare@suse.com> Tested-by: Ondrej Zary <linux@rainbow-software.org> Tested-by: Michael Schmitz <schmitzmic@gmail.com> Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2016-01-06ncr5380: Introduce unbound workqueueFinn Thain
Allocate a work queue that will permit busy waiting and sleeping. This means NCR5380_init() can potentially fail, so add this error path. Signed-off-by: Finn Thain <fthain@telegraphics.com.au> Reviewed-by: Hannes Reinecke <hare@suse.com> Tested-by: Ondrej Zary <linux@rainbow-software.org> Tested-by: Michael Schmitz <schmitzmic@gmail.com> Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2016-01-06ncr5380: Eliminate USLEEP_WAITLONG delayFinn Thain
Linux 2.1.105 introduced the USLEEP_WAITLONG delay, apparently "needed for Mustek scanners". It is intended to stall the issue queue for 5 seconds. There are a number of problems with this. 1. Only g_NCR5380 enables the delay, which implies that the other five drivers using the NCR5380.c core driver remain incompatible with Mustek scanners. 2. The delay is not implemented by atari_NCR5380.c, which is problematic for re-unifying the two core driver forks. 3. The delay is implemented using NCR5380_set_timer() which makes it unreliable. A new command queued by the mid-layer cancels the delay. 4. The delay is applied indiscriminately in several situations in which NCR5380_select() returns -1. These are-- reselection by the target, failure of the target to assert BSY, and failure of the target to assert REQ. It's clear from the comments that USLEEP_WAITLONG is not relevant to the reselection case. And reportedly, these scanners do not disconnect. 5. atari_NCR5380.c was forked before Linux 2.1.105, so it was spared some of the damage done to NCR5380.c. In this case, the atari_NCR5380.c core driver was more standard-compliant and may not have needed any workaround like the USLEEP_WAITLONG kludge. The compliance issue was addressed in the previous patch. If these scanners still don't work, we need a better solution. Retrying selection until EH aborts a command offers equivalent robustness. Bugs in the existing driver prevent EH working correctly but this is addressed in a subsequent patch. Remove USLEEP_WAITLONG. Signed-off-by: Finn Thain <fthain@telegraphics.com.au> Reviewed-by: Hannes Reinecke <hare@suse.com> Tested-by: Ondrej Zary <linux@rainbow-software.org> Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>