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From 0f201366b80bb62665636fab69f508842946161c Mon Sep 17 00:00:00 2001 |
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From: Finn Thain <fthain@telegraphics.com.au> |
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Date: Tue, 16 Oct 2018 16:31:25 +1100 |
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Subject: [PATCH 091/145] scsi: esp_scsi: Track residual for PIO transfers |
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|
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[ Upstream commit fd47d919d0c336e7c22862b51ee94927ffea227a ] |
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|
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If a target disconnects during a PIO data transfer the command may fail |
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when the target reconnects: |
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|
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scsi host1: DMA length is zero! |
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scsi host1: cur adr[04380000] len[00000000] |
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|
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The scsi bus is then reset. This happens because the residual reached |
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zero before the transfer was completed. |
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|
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The usual residual calculation relies on the Transfer Count registers. |
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That works for DMA transfers but not for PIO transfers. Fix the problem |
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by storing the PIO transfer residual and using that to correctly |
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calculate bytes_sent. |
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|
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Fixes: 6fe07aaffbf0 ("[SCSI] m68k: new mac_esp scsi driver") |
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Tested-by: Stan Johnson <userm57@yahoo.com> |
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Signed-off-by: Finn Thain <fthain@telegraphics.com.au> |
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Tested-by: Michael Schmitz <schmitzmic@gmail.com> |
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Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com> |
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Signed-off-by: Sasha Levin <sashal@kernel.org> |
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--- |
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drivers/scsi/esp_scsi.c | 1 + |
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drivers/scsi/esp_scsi.h | 2 ++ |
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drivers/scsi/mac_esp.c | 2 ++ |
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3 files changed, 5 insertions(+) |
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|
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diff --git a/drivers/scsi/esp_scsi.c b/drivers/scsi/esp_scsi.c |
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index c3fc34b9964d..9e5d3f7d29ae 100644 |
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--- a/drivers/scsi/esp_scsi.c |
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+++ b/drivers/scsi/esp_scsi.c |
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@@ -1338,6 +1338,7 @@ static int esp_data_bytes_sent(struct esp *esp, struct esp_cmd_entry *ent, |
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|
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bytes_sent = esp->data_dma_len; |
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bytes_sent -= ecount; |
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+ bytes_sent -= esp->send_cmd_residual; |
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|
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/* |
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* The am53c974 has a DMA 'pecularity'. The doc states: |
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diff --git a/drivers/scsi/esp_scsi.h b/drivers/scsi/esp_scsi.h |
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index 8163dca2071b..a77772777a30 100644 |
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--- a/drivers/scsi/esp_scsi.h |
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+++ b/drivers/scsi/esp_scsi.h |
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@@ -540,6 +540,8 @@ struct esp { |
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|
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void *dma; |
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int dmarev; |
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+ |
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+ u32 send_cmd_residual; |
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}; |
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|
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/* A front-end driver for the ESP chip should do the following in |
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diff --git a/drivers/scsi/mac_esp.c b/drivers/scsi/mac_esp.c |
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index eb551f3cc471..71879f2207e0 100644 |
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--- a/drivers/scsi/mac_esp.c |
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+++ b/drivers/scsi/mac_esp.c |
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@@ -427,6 +427,8 @@ static void mac_esp_send_pio_cmd(struct esp *esp, u32 addr, u32 esp_count, |
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scsi_esp_cmd(esp, ESP_CMD_TI); |
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} |
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} |
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+ |
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+ esp->send_cmd_residual = esp_count; |
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} |
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|
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static int mac_esp_irq_pending(struct esp *esp) |
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-- |
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2.19.1 |
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