kernel.git/drivers/scsi/esp_scsi.c, branch linux-4.4.y

scsi: esp_scsi: Track residual for PIO transfers

2018-11-21T08:27:32Z

[ Upstream commit fd47d919d0c336e7c22862b51ee94927ffea227a ] If a target disconnects during a PIO data transfer the command may fail when the target reconnects: scsi host1: DMA length is zero! scsi host1: cur adr[04380000] len[00000000] The scsi bus is then reset. This happens because the residual reached zero before the transfer was completed. The usual residual calculation relies on the Transfer Count registers. That works for DMA transfers but not for PIO transfers. Fix the problem by storing the PIO transfer residual and using that to correctly calculate bytes_sent. Fixes: 6fe07aaffbf0 ("[SCSI] m68k: new mac_esp scsi driver") Tested-by: Stan Johnson Signed-off-by: Finn Thain Tested-by: Michael Schmitz Signed-off-by: Martin K. Petersen Signed-off-by: Sasha Levin Signed-off-by: Greg Kroah-Hartman

scsi: use host wide tags by default

2015-11-10T01:11:57Z

This patch changes the !blk-mq path to the same defaults as the blk-mq I/O path by always enabling block tagging, and always using host wide tags. We've had blk-mq available for a few releases so bugs with this mode should have been ironed out, and this ensures we get better coverage of over tagging setup over different configs. Signed-off-by: Christoph Hellwig Acked-by: Jens Axboe Reviewed-by: Hannes Reinecke Signed-off-by: James Bottomley

esp_scsi: remove check for ESP_MAX_TAGS

2015-01-09T14:44:23Z

'num_tags' is an unsigned char, so the check for 'ESP_MAX_TAGS' (which is set to 256) is pointless. Acked-by: Geert Uytterhoeven Signed-off-by: Hannes Reinecke Signed-off-by: Christoph Hellwig

esp_scsi: enable CONFIG2_FENAB for am53c974

2014-11-24T15:13:17Z

CONFIG2_FENAB ('feature enable') changed definition between chip revisions, from 'Latch SCSI Phase' to 'Latch SCSI Phase, display chip ID upon reset, and enable 24 bit addresses'. So only enable it for am53c974 where we know what it's doing. Acked-by: David S. Miller Reviewed-by: Paolo Bonzini Signed-off-by: Hannes Reinecke Signed-off-by: Christoph Hellwig

esp_scsi: let DMA driver provide a config2 value

2014-11-24T15:13:17Z

On PCscsi, the FENAB configuration also enables 24-bit DMA transfer lengths (and provides the chip id in TCHI after reset). We want to be able to enable this parameter from the DMA driver. Check if the caller of scsi_esp_register provided a value for esp->config2. If this is the case, assume this is not an ESP100, skip the detection phase and leave esp->config2 untouched. It will be used in esp_reset_esp. Reviewed-by: Hannes Reinecke Acked-by: David S. Miller Signed-off-by: Paolo Bonzini Signed-off-by: Christoph Hellwig

esp_scsi: correctly detect am53c974

2014-11-24T15:13:16Z

The am53c974 returns the same ID as the FAS236, but implements things slightly differently. So detect the am53c974 by checking for ESP_CONFIG4 register. Reviewed-by: Paolo Bonzini Signed-off-by: Hannes Reinecke Signed-off-by: Christoph Hellwig

am53c974: BLAST residual handling

2014-11-24T15:13:15Z

The am53c974 has an design issue where a single byte might be left in the SCSI FIFO after a DMA transfer. As the handling code is currently untested add a WARN_ON() statement here. Reviewed-by: Paolo Bonzini Acked-by: David S. Miller Signed-off-by: Hannes Reinecke Signed-off-by: Christoph Hellwig

esp_scsi: use FIFO for command submission

2014-11-24T15:10:24Z

Using DMA for command submission has the drawback that it might generate additional DMA completion interrupts after the command has been submitted to the device. Additionally the am53c974 has a design flaw causing it to generate spurious interrupts even though DMA completion interrupts are not enabled. This can be avoided by using the FIFO for command submission. Reviewed-by: Paolo Bonzini Acked-by: David S. Miller Signed-off-by: Hannes Reinecke Signed-off-by: Christoph Hellwig

esp_scsi: read status registers

2014-11-24T15:10:24Z

A read to ESP_INTRPT will clear ESP_STATUS and ESP_SSTEP. So read all status registers in one go to avoid losing information. Reviewed-by: Paolo Bonzini Acked-by: David S. Miller Signed-off-by: Hannes Reinecke Signed-off-by: Christoph Hellwig

esp_scsi: debug event and command

2014-11-24T15:10:23Z

Add new debug definitions for event and command logging. Reviewed-by: Paolo Bonzini Acked-by: David S. Miller Signed-off-by: Hannes Reinecke Signed-off-by: Christoph Hellwig