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2018-09-28scsi: NCR5380: Have NCR5380_select() return a boolFinn Thain1-1/+1
The return value is taken to mean "retry" or "don't retry". Change it to bool to improve readability. Fix related comments. No functional change. Tested-by: Michael Schmitz <schmitzmic@gmail.com> Signed-off-by: Finn Thain <fthain@telegraphics.com.au> Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2017-11-02License cleanup: add SPDX GPL-2.0 license identifier to files with no licenseGreg Kroah-Hartman1-0/+1
Many source files in the tree are missing licensing information, which makes it harder for compliance tools to determine the correct license. By default all files without license information are under the default license of the kernel, which is GPL version 2. Update the files which contain no license information with the 'GPL-2.0' SPDX license identifier. The SPDX identifier is a legally binding shorthand, which can be used instead of the full boiler plate text. This patch is based on work done by Thomas Gleixner and Kate Stewart and Philippe Ombredanne. How this work was done: Patches were generated and checked against linux-4.14-rc6 for a subset of the use cases: - file had no licensing information it it. - file was a */uapi/* one with no licensing information in it, - file was a */uapi/* one with existing licensing information, Further patches will be generated in subsequent months to fix up cases where non-standard license headers were used, and references to license had to be inferred by heuristics based on keywords. The analysis to determine which SPDX License Identifier to be applied to a file was done in a spreadsheet of side by side results from of the output of two independent scanners (ScanCode & Windriver) producing SPDX tag:value files created by Philippe Ombredanne. Philippe prepared the base worksheet, and did an initial spot review of a few 1000 files. The 4.13 kernel was the starting point of the analysis with 60,537 files assessed. Kate Stewart did a file by file comparison of the scanner results in the spreadsheet to determine which SPDX license identifier(s) to be applied to the file. She confirmed any determination that was not immediately clear with lawyers working with the Linux Foundation. Criteria used to select files for SPDX license identifier tagging was: - Files considered eligible had to be source code files. - Make and config files were included as candidates if they contained >5 lines of source - File already had some variant of a license header in it (even if <5 lines). All documentation files were explicitly excluded. The following heuristics were used to determine which SPDX license identifiers to apply. - when both scanners couldn't find any license traces, file was considered to have no license information in it, and the top level COPYING file license applied. For non */uapi/* files that summary was: SPDX license identifier # files ---------------------------------------------------|------- GPL-2.0 11139 and resulted in the first patch in this series. If that file was a */uapi/* path one, it was "GPL-2.0 WITH Linux-syscall-note" otherwise it was "GPL-2.0". Results of that was: SPDX license identifier # files ---------------------------------------------------|------- GPL-2.0 WITH Linux-syscall-note 930 and resulted in the second patch in this series. - if a file had some form of licensing information in it, and was one of the */uapi/* ones, it was denoted with the Linux-syscall-note if any GPL family license was found in the file or had no licensing in it (per prior point). Results summary: SPDX license identifier # files ---------------------------------------------------|------ GPL-2.0 WITH Linux-syscall-note 270 GPL-2.0+ WITH Linux-syscall-note 169 ((GPL-2.0 WITH Linux-syscall-note) OR BSD-2-Clause) 21 ((GPL-2.0 WITH Linux-syscall-note) OR BSD-3-Clause) 17 LGPL-2.1+ WITH Linux-syscall-note 15 GPL-1.0+ WITH Linux-syscall-note 14 ((GPL-2.0+ WITH Linux-syscall-note) OR BSD-3-Clause) 5 LGPL-2.0+ WITH Linux-syscall-note 4 LGPL-2.1 WITH Linux-syscall-note 3 ((GPL-2.0 WITH Linux-syscall-note) OR MIT) 3 ((GPL-2.0 WITH Linux-syscall-note) AND MIT) 1 and that resulted in the third patch in this series. - when the two scanners agreed on the detected license(s), that became the concluded license(s). - when there was disagreement between the two scanners (one detected a license but the other didn't, or they both detected different licenses) a manual inspection of the file occurred. - In most cases a manual inspection of the information in the file resulted in a clear resolution of the license that should apply (and which scanner probably needed to revisit its heuristics). - When it was not immediately clear, the license identifier was confirmed with lawyers working with the Linux Foundation. - If there was any question as to the appropriate license identifier, the file was flagged for further research and to be revisited later in time. In total, over 70 hours of logged manual review was done on the spreadsheet to determine the SPDX license identifiers to apply to the source files by Kate, Philippe, Thomas and, in some cases, confirmation by lawyers working with the Linux Foundation. Kate also obtained a third independent scan of the 4.13 code base from FOSSology, and compared selected files where the other two scanners disagreed against that SPDX file, to see if there was new insights. The Windriver scanner is based on an older version of FOSSology in part, so they are related. Thomas did random spot checks in about 500 files from the spreadsheets for the uapi headers and agreed with SPDX license identifier in the files he inspected. For the non-uapi files Thomas did random spot checks in about 15000 files. In initial set of patches against 4.14-rc6, 3 files were found to have copy/paste license identifier errors, and have been fixed to reflect the correct identifier. Additionally Philippe spent 10 hours this week doing a detailed manual inspection and review of the 12,461 patched files from the initial patch version early this week with: - a full scancode scan run, collecting the matched texts, detected license ids and scores - reviewing anything where there was a license detected (about 500+ files) to ensure that the applied SPDX license was correct - reviewing anything where there was no detection but the patch license was not GPL-2.0 WITH Linux-syscall-note to ensure that the applied SPDX license was correct This produced a worksheet with 20 files needing minor correction. This worksheet was then exported into 3 different .csv files for the different types of files to be modified. These .csv files were then reviewed by Greg. Thomas wrote a script to parse the csv files and add the proper SPDX tag to the file, in the format that the file expected. This script was further refined by Greg based on the output to detect more types of files automatically and to distinguish between header and source .c files (which need different comment types.) Finally Greg ran the script using the .csv files to generate the patches. Reviewed-by: Kate Stewart <kstewart@linuxfoundation.org> Reviewed-by: Philippe Ombredanne <pombredanne@nexb.com> Reviewed-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-02-01scsi: ncr5380: Clean up dead code and redundant macro usageFinn Thain1-7/+0
Remove dead code inside #if 0 conditionals. Remove the #ifdef __KERNEL__ test, since NCR5380.h has no definitions that relate to userspace code. Remove two redundant macro definitions which were overlooked in commit e9db3198e08b ("sun3_scsi: Adopt NCR5380.c core driver"). 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>
2017-02-01scsi: ncr5380: Shorten host info string by removing unused option macrosFinn Thain1-9/+1
The DIFFERENTIAL and PARITY option macros are unused: no supported hardware uses differential signalling and the core driver never implemented parity checking. These options just waste space in the host info string. While we are here, fix a typo in the NCR5380_info() kernel-doc comment. 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>
2016-12-09scsi: g_NCR5380: Use probe_irq_*() for IRQ probingOndrej Zary1-11/+0
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>
2016-11-09scsi: ncr5380: Use correct types for DMA routinesFinn Thain1-0/+25
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>
2016-11-09scsi: ncr5380: Expedite register pollingFinn Thain1-0/+3
Avoid the call to NCR5380_poll_politely2() when possible. The call is easily short-circuited on the PIO fast path, using the inline wrapper. This requires that the NCR5380_read macro be made available before any #include "NCR5380.h" so a few declarations have to be moved too. 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>
2016-11-09scsi: ncr5380: Pass hostdata pointer to register polling routinesFinn Thain1-3/+3
Pass a NCR5380_hostdata struct pointer to the board-specific routines instead of a Scsi_Host struct pointer. This reduces pointer chasing in the PIO and PDMA fast paths. The old way was a mistake because it is slow and the board-specific code is not concerned with the mid-layer. 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>
2016-11-09scsi: ncr5380: Use correct types for device register accessorsFinn Thain1-2/+5
For timeout values adopt unsigned long, which is the type of jiffies etc. For chip register values and bit masks pass u8, which is the return type of readb, inb etc. For device register offsets adopt unsigned int, as it is suitable for adding to base addresses. Pass the NCR5380_hostdata pointer to the board-specific routines instead of the Scsi_Host pointer. The board-specific code is concerned with hardware and not with SCSI protocol or the mid-layer. 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>
2016-11-09scsi: ncr5380: Store IO ports and addresses in host private dataFinn Thain1-0/+5
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>
2016-11-09scsi: ncr5380: Improve hostdata struct member alignment and cache-abilityFinn Thain1-20/+20
Re-order struct members so that hot data lies at the beginning of the struct and cold data at the end. Improve the comments while we're here. 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>
2016-11-09scsi: ncr5380: Increase register polling limitFinn Thain1-1/+1
If NCR5380_poll_politely() is called under irq lock, the polling time limit is clamped to avoid a spike in interrupt latency. When not under irq lock, the same polling time limit acts as the worst case delay between schedule() calls. During PDMA (under irq lock) I've found that the 10 ms time limit is sometimes too short, and leads to the error message, sd 0:0:0:0: [sda] tag#1 macscsi_pread: !REQ and !ACK This particular target identifies itself as a QUANTUM DAYTONA514S. It seems to be slower to assert ACK than the other targets I've tested. This patch solves the problem by increasing the polling timeout. 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>
2016-11-09scsi: ncr5380: Simplify register polling limitFinn Thain1-1/+4
When polling a device register under irq lock the polling loop terminates after a given number of jiffies. Make this timeout independent of the HZ setting. All 5380 drivers benefit from this patch, which optimizes the PIO fast path, because they all use PIO transfers (for phases other than DATA IN and DATA OUT). Some cards support only PIO transfers (even for DATA phases). CPU cycles are scarce on some of these systems, so a small improvement here makes a big difference. 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>
2016-09-14scsi: ncr5380: Improve interrupt latency during PIO tranfersFinn Thain1-0/+2
Large PIO transfers are broken up into chunks to try to avoid disabling local IRQs for long periods. But IRQs are still disabled for too long and this causes SCC FIFO overruns during serial port transfers. This patch reduces the PIO chunk size to reduce interrupt latency to something on the order of milliseconds, at the expense of additional CPU overhead from extra iterations of the NCR5380_main() loop. That CPU overhead is a problem for slow machines (e.g. mac_scsi on 25 MHz 68030) but these machines generally use PDMA not PIO. This patch doesn't make the overhead any worse on my Mac LC III (because it only gets about 510 accesses per ms). This patch decreases disk performance by a fraction of one percent for dmx3191d on my 333 MHz PowerPC 750. Other affected hardware (such as g_NCR5380 on x86) was not tested but 5380 ISA cards generally use PDMA and not PIO. [mkp: fix whitespace] Signed-off-by: Finn Thain <fthain@telegraphics.com.au> Reviewed-by: Laurence Oberman <loberman@redhat.com> Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2016-08-31scsi: ncr5380: Avoid a compiler warningFinn Thain1-1/+7
With commit 3a0f64bfa907 ("mac_scsi: Fix pseudo DMA implementation") some versions of gcc now warn: In file included from drivers/scsi/mac_scsi.c:335: drivers/scsi/NCR5380.h:295: warning: `NCR5380_poll_politely' declared inline after being called drivers/scsi/NCR5380.h:295: warning: previous declaration of `NCR5380_poll_politely' was here Avoid this by defining NCR5380_poll_politely() in NCR5380.h. [mkp: checkpatch warnings] Suggested-by: Geert Uytterhoeven <geert@linux-m68k.org> Signed-off-by: Finn Thain <fthain@telegraphics.com.au> Tested-by: Geert Uytterhoeven <geert@linux-m68k.org> Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2016-04-11mac_scsi: Fix pseudo DMA implementationFinn Thain1-0/+2
Fix various issues: Comments about bus errors are incorrect. The PDMA asm must return the size of the memory access that faulted so the transfer count can be adjusted accordingly. A phase change may cause a bus error but should not be treated as failure. A bus error does not always imply a phase change and generally the transfer may continue. Scatter/gather doesn't seem to work with PDMA due to overruns. This is a pity because peak throughput seems to double with SG_ALL. Tested on a Mac LC III and a PowerBook 520. 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 Thain1-4/+0
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 disused atari_NCR5380.c core driverFinn Thain1-19/+0
Now that atari_scsi and sun3_scsi have been converted to use the NCR5380.c core driver, remove atari_NCR5380.c. Also remove the last vestiges of its Tagged Command Queueing implementation from the wrapper drivers. The TCQ support in atari_NCR5380.c is abandoned by this patch. It is not merged into the remaining core driver because, 1) atari_scsi defines SUPPORT_TAGS but leaves FLAG_TAGGED_QUEUING disabled by default, which indicates that it is mostly undesirable. 2) I'm told that it doesn't work correctly when enabled. 3) The algorithm does not make use of block layer tags which it will have to do because scmd->tag is deprecated. 4) sun3_scsi doesn't define SUPPORT_TAGS at all, yet the the SUPPORT_TAGS macro interacts with the CONFIG_SUN3 macro in 'interesting' ways. 5) Compile-time configuration with macros like SUPPORT_TAGS caused the configuration space to explode, leading to untestable and unmaintainable code that is too hard to reason about. The merge_contiguous_buffers() code is also abandoned. This was unused by sun3_scsi. Only atari_scsi used it and then only on TT, because only TT supports scatter/gather. I suspect that the TT would work fine with ENABLE_CLUSTERING instead. If someone can benchmark the difference then perhaps the merge_contiguous_buffers() code can be be justified. Until then we are better off without the extra complexity. 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 Thain1-4/+0
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 Thain1-1/+1
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 REAL_DMA and REAL_DMA_POLL macrosFinn Thain1-112/+0
For the NCR5380.c core driver, these macros are never used. If REAL_DMA were to be defined, compilation would fail. For the atari_NCR5380.c core driver, REAL_DMA is always defined. Hence these macros are pointless. 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>
2016-01-07ncr5380: Use runtime register mappingOndrej Zary1-12/+1
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>
2016-01-07ncr5380: Fix EH during arbitration and selectionFinn Thain1-2/+2
During arbitration and selection, the relevant command is invisible to exception handlers and can be found only in a pointer on the stack of a different thread. When eh_abort_handler can't find a given command, it can't decide whether that command was completed already or is still in arbitration or selection phase. But it must return either SUCCESS (e.g. command completed earlier) or FAILED (could not abort the nexus, try bus reset). The solution is to make sure all commands belonging to the LLD are always visible to exception handlers. Add another scsi_cmnd pointer to the hostdata struct to track the command in arbitration or selection phase. Replace 'retain_dma_irq' with the new 'selecting' pointer, to bring atari_NCR5380.c into line with NCR5380.c. 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>
2016-01-07ncr5380: Fix autosense bugsFinn Thain1-0/+2
NCR5380_information_transfer() may re-queue a command for autosense, after calling scsi_eh_prep_cmnd(). This creates several possibilities: 1. Reselection may intervene before the re-queued command gets processed. If the reconnected command then undergoes autosense, this causes the scsi_eh_save data from the previous command to be overwritten. 2. After NCR5380_information_transfer() calls scsi_eh_prep_cmnd(), a new REQUEST SENSE command may arrive. This would be queued ahead of any command already undergoing autosense, which means the scsi_eh_save data might be restored to the wrong command. 3. After NCR5380_information_transfer() calls scsi_eh_prep_cmnd(), eh_abort_handler() may abort the command. But the scsi_eh_save data is not discarded, which means the scsi_eh_save data might be incorrectly restored to the next REQUEST SENSE command issued. This patch adds a new autosense list so that commands that are re-queued because of a CHECK CONDITION result can be kept apart from the REQUEST SENSE commands that arrive via queuecommand. This patch also adds a function dedicated to dequeueing and preparing the next command for processing. By refactoring the main loop in this way, scsi_eh_save takes place when an autosense command is dequeued rather than when re-queued. 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>
2016-01-07ncr5380: Use standard list data structureFinn Thain1-2/+14
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>
2016-01-07ncr5380: Remove redundant volatile qualifiersFinn Thain1-6/+6
The hostdata struct is now protected by a spin lock so the volatile qualifiers are redundant. Remove them. 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>
2016-01-07ncr5380: Remove H_NO macro and introduce dsprintkFinn Thain1-0/+5
Replace all H_NO and some HOSTNO macros (both peculiar to atari_NCR5380.c) with a new dsprintk macro that's more useful and more consistent. The new macro avoids a lot of boilerplate in new code in subsequent patches. Keep NCR5380.c in sync. Remaining HOSTNO macros are removed as side-effects of subsequent patches. 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>
2016-01-07ncr5380: Change instance->host_lock to hostdata->lockFinn Thain1-0/+1
NCR5380.c presently uses the instance->host_lock spin lock. Convert this to a new spin lock that protects the NCR5380_hostdata struct. atari_NCR5380.c previously used local_irq_save/restore() rather than a spin lock. Convert this to hostdata->lock in irq mode. For SMP platforms, the interrupt handler now also acquires the spin lock. This brings all locking in the two core drivers into agreement. Adding this locking also means that a bunch of volatile qualifiers can be removed from the members of the NCR5380_hostdata struct. This is done in a subsequent patch. Proper locking will allow the abort handler to locate a command being aborted. This is presently impossible if the abort handler is invoked when the command has been moved from a queue to a pointer on the stack. (If eh_abort_handler can't determine whether a command has been completed or is still being processed then it can't decide whether to return success or failure.) The hostdata spin lock is now held when calling NCR5380_select() and NCR5380_information_transfer(). Where possible, the lock is dropped for polling and PIO transfers. Clean up the now-redundant SELECT_ENABLE_REG writes, that used to provide limited mutual exclusion between information_transfer() and reselect(). Accessing hostdata->connected without data races means taking the lock; cleanup these accesses. The new spin lock falls away for m68k and other UP builds, so this should have little impact there. In the SMP case the new lock should be uncontested even when the SCSI bus is contested. 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>
2016-01-07ncr5380: Remove redundant ICR_ARBITRATION_LOST test and eliminate FLAG_DTC3181EFinn Thain1-1/+0
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>
2016-01-07ncr5380: Cleanup #include directivesFinn Thain1-0/+4
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>
2016-01-07ncr5380: Replace redundant flags with FLAG_NO_DMA_FIXUPFinn Thain1-3/+1
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>
2016-01-07ncr5380: Standardize work queueing algorithmFinn Thain1-1/+0
The complex main_running/queue_main mechanism is peculiar to atari_NCR5380.c. It isn't SMP safe and offers little value given that the work queue already offers concurrency management. Remove this complexity to bring atari_NCR5380.c closer to NCR5380.c. It is not a good idea to call the information transfer state machine from queuecommand because, according to Documentation/scsi/scsi_mid_low_api.txt that could happen in soft irq context. Fix this. Signed-off-by: Finn Thain <fthain@telegraphics.com.au> Reviewed-by: Hannes Reinecke <hare@suse.com> Tested-by: Michael Schmitz <schmitzmic@gmail.com> Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2016-01-07ncr5380: Use work_struct instead of delayed_workFinn Thain1-1/+0
Each host instance now has it's own work queue so the main() work item can sleep when necessary. That means we can use a simple work item rather than a delayed work item. This brings NCR5380.c closer to atari_NCR5380.c. 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>
2016-01-07ncr5380: Rework disconnect versus poll logicFinn Thain1-11/+0
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>
2016-01-07ncr5380: Eliminate selecting stateFinn Thain1-2/+0
Linux v2.1.105 changed the algorithm for polling for the BSY signal in NCR5380_select() and NCR5380_main(). Presently, this code has a bug. Back then, NCR5380_set_timer(hostdata, 1) meant reschedule main() after sleeping for 10 ms. Repeated 25 times this provided the recommended 250 ms selection time-out delay. This got broken when HZ became configurable. We could fix this but there's no need to reschedule the main loop. This BSY polling presently happens when the NCR5380_main() work queue item calls NCR5380_select(), which in turn schedules NCR5380_main(), which calls NCR5380_select() again, and so on. This algorithm is a deviation from the simpler one in atari_NCR5380.c. The extra complexity and state is pointless. There's no reason to stop selection half-way and return to to the main loop when the main loop can do nothing useful until selection completes. So just poll for BSY. We can sleep while polling now that we have a suitable workqueue. 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>
2016-01-07ncr5380: Sleep when polling, if possibleFinn Thain1-0/+1
When in process context, sleep during polling if doing so won't add significant latency. In interrupt context or if the lock is held, poll briefly then give up. Keep both core drivers in sync. Calibrate busy-wait iterations to allow for variation in chip register access times between different 5380 hardware implementations. 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>
2016-01-07ncr5380: Introduce unbound workqueueFinn Thain1-0/+1
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>
2016-01-07ncr5380: Always escalate bad target time-out in NCR5380_select()Finn Thain1-6/+0
Remove the restart_select and targets_present variables introduced in Linux v1.1.38. The former was used only for a questionable debug printk and the latter "so we can call a select failure a retryable condition". Well, retrying select failure in general is a different problem to a target that doesn't assert BSY. We need to handle these two cases differently; the latter case can be left to the SCSI ML. 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>
2016-01-07ncr5380: Remove unused hostdata->aborted flagFinn Thain1-1/+0
The aborted flag was introduced in v1.1.38 but never used. Remove 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>
2016-01-07atari_NCR5380: Remove RESET_BOOT, CONFIG_ATARI_SCSI_TOSHIBA_DELAY and ↵Finn Thain1-0/+1
CONFIG_ATARI_SCSI_RESET_BOOT The atari_NCR5380.c core driver now takes care of bus reset upon driver initialization if required (same as NCR5380.c). Move the Toshiba CD-ROM support into the core driver, enabled with a host flag, so that all NCR5380 drivers can make use of it. Drop the RESET_BOOT macros and the ATARI_SCSI_RESET_BOOT and ATARI_SCSI_TOSHIBA_DELAY Kconfig symbols, which are now redundant. Remove the atari_scsi_reset_boot(), mac_scsi_reset_boot() and sun3_scsi_reset_boot() routines. None of this duplicated code is needed now that all drivers can use NCR5380_maybe_reset_bus(). This brings atari_scsi, mac_scsi and sun3_scsi into line with all of the other NCR5380 drivers. The bus reset may raise an interrupt. That would be new behaviour for atari_scsi only when CONFIG_ATARI_SCSI_RESET_BOOT=n. The ST DMA interrupt is not assigned to atari_scsi at this stage, so CONFIG_ATARI_SCSI_RESET_BOOT=y may well be problematic already. Regardless, do_reset() now raises and clears the interrupt within local_irq_save/restore which should avoid problems. 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>
2016-01-07ncr5380: Split NCR5380_init() into two functionsFinn Thain1-0/+1
This patch splits the NCR5380_init() function into two parts, similar to the scheme used with atari_NCR5380.c. This avoids two problems. Firstly, NCR5380_init() may perform a bus reset, which would cause the chip to assert IRQ. The chip is unable to mask its bus reset interrupt. Drivers can't call request_irq() before calling NCR5380_init(), because initialization must happen before the interrupt handler executes. If driver initialization causes an interrupt it may be problematic on some platforms. To avoid that, first move the bus reset code into NCR5380_maybe_reset_bus(). Secondly, NCR5380_init() contains some board-specific interrupt setup code for the NCR53C400 that does not belong in the core driver. In moving this code, better not re-order interrupt initialization and bus reset. Again, the solution is to move the bus reset code into NCR5380_maybe_reset_bus(). 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>
2016-01-07ncr5380: Remove more pointless macrosFinn Thain1-3/+0
ASM macro is never defined. rtrc in pas16.c is not used. NCR5380_map_config, do_NCR5380_intr, do_t128_intr and do_pas16_intr are unused. NCR_NOT_SET harms readability. Remove them. 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>
2014-11-20atari_NCR5380: Move static co-routine variables to host dataFinn Thain1-0/+2
Unlike NCR5380.c, the atari_NCR5380.c core driver is limited to a single instance because co-routine state is stored globally. Fix this by removing the static scsi host pointer. For the co-routine, obtain this pointer from the work_struct pointer instead. For the interrupt handler, obtain it from the dev_id argument. Signed-off-by: Finn Thain <fthain@telegraphics.com.au> Reviewed-by: Hannes Reinecke <hare@suse.de> Tested-by: Michael Schmitz <schmitzmic@gmail.com> Signed-off-by: Christoph Hellwig <hch@lst.de>
2014-11-20atari_NCR5380: Move static TagAlloc array to host dataFinn Thain1-0/+12
The atari_NCR5380.c core driver keeps some per-host data in a static variable which limits the driver to a single instance. Fix this by moving TagAlloc to the hostdata struct. Signed-off-by: Finn Thain <fthain@telegraphics.com.au> Reviewed-by: Hannes Reinecke <hare@suse.de> Tested-by: Michael Schmitz <schmitzmic@gmail.com> Signed-off-by: Christoph Hellwig <hch@lst.de>
2014-11-20atari_NCR5380: Introduce FLAG_TAGGED_QUEUINGFinn Thain1-0/+1
The static variable setup_use_tagged_queuing is declared in mac_scsi.c, sun3_scsi.c and atari_scsi.c and doesn't belong in the core driver. None of the other NCR5380 drivers suffer from this layering issue which makes merging the core drivers more difficult and will likely hinder plans for future use of platform data to configure the driver. Replace the static variable with a host flag. This way it can be reported along with the other flags. Signed-off-by: Finn Thain <fthain@telegraphics.com.au> Reviewed-by: Hannes Reinecke <hare@suse.de> Tested-by: Michael Schmitz <schmitzmic@gmail.com> Signed-off-by: Christoph Hellwig <hch@lst.de>
2014-11-20atari_NCR5380: Refactor Falcon special casesFinn Thain1-0/+4
Make the atari_NCR5380.c core driver usable by sun3_scsi, mac_scsi and others by moving some of the Falcon-specific code out of the core driver: !IS_A_TT, atari_read_overruns and falcon_dont_release. Replace these with hostdata variables and flags. FLAG_CHECK_LAST_BYTE_SENT is unused in atari_NCR5380.c so don't set it. Signed-off-by: Finn Thain <fthain@telegraphics.com.au> Reviewed-by: Hannes Reinecke <hare@suse.de> Tested-by: Michael Schmitz <schmitzmic@gmail.com> Signed-off-by: Christoph Hellwig <hch@lst.de>
2014-11-20ncr5380: Drop legacy scsi.h includeFinn Thain1-5/+5
Convert Scsi_Cmnd to struct scsi_cmnd and drop the #include "scsi.h". The sun3_NCR5380.c core driver already uses struct scsi_cmnd so converting the other core drivers reduces the diff which makes them easier to unify. Signed-off-by: Finn Thain <fthain@telegraphics.com.au> Reviewed-by: Hannes Reinecke <hare@suse.de> Tested-by: Michael Schmitz <schmitzmic@gmail.com> Signed-off-by: Christoph Hellwig <hch@lst.de>
2014-11-20ncr5380: Remove *_RELEASE macrosFinn Thain1-5/+0
The *_RELEASE macros don't tell me anything. In some cases the version in the macro contradicts the version in the comments. Anyway, the Linux kernel version is sufficient information. Remove these macros to improve readability. Signed-off-by: Finn Thain <fthain@telegraphics.com.au> Reviewed-by: Hannes Reinecke <hare@suse.de> Tested-by: Michael Schmitz <schmitzmic@gmail.com> Signed-off-by: Christoph Hellwig <hch@lst.de>
2014-11-20ncr5380: Move static PDMA spin counters to host dataFinn Thain1-0/+4
Static variables from dtc.c and pas16.c should not appear in the core NCR5380.c driver. Aside from being a layering issue this worsens the divergence between the three core driver variants (atari_NCR5380.c and sun3_NCR5380.c don't support PSEUDO_DMA) and it can mean multiple hosts share the same counters. Fix this by making the pseudo DMA spin counters in the core more generic. This also avoids the abuse of the {DTC,PAS16}_PUBLIC_RELEASE macros, so they can be removed. oak.c doesn't use PDMA and hence it doesn't use the counters and hence it needs no write_info() method. Remove it. Signed-off-by: Finn Thain <fthain@telegraphics.com.au> Reviewed-by: Hannes Reinecke <hare@suse.de> Tested-by: Michael Schmitz <schmitzmic@gmail.com> Signed-off-by: Christoph Hellwig <hch@lst.de>
2014-11-20ncr5380: Cleanup host info() methodsFinn Thain1-1/+2
If the host->info() method is not set, then host->name is used by default. For atari_scsi, that is exactly the same text. So remove the redundant info() method. Keep sun3_scsi.c in line with atari_scsi. Some NCR5380 drivers return an empty string from the info() method (arm/cumana_1.c arm/oak.c mac_scsi.c) while other drivers use the default (dmx3191d dtc.c g_NCR5380.c pas16.c t128.c). Implement a common info() method to replace a lot of duplicated code which the various drivers use to announce the same information. This replaces most of the (deprecated) show_info() output and all of the NCR5380_print_info() output. This also eliminates a bunch of code in g_NCR5380 which just duplicates functionality in the core driver. Signed-off-by: Finn Thain <fthain@telegraphics.com.au> Reviewed-by: Hannes Reinecke <hare@suse.de> Tested-by: Michael Schmitz <schmitzmic@gmail.com> Signed-off-by: Christoph Hellwig <hch@lst.de>