linux-imx

/* -*- mode: c; c-basic-offset: 8 -*- */

​

/* NCR (or Symbios) 53c700 and 53c700-66 Driver

 *

 * Copyright (C) 2001 by James.Bottomley@HansenPartnership.com

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​

/* Notes:

 *

 * This driver is designed exclusively for these chips (virtually the

 * earliest of the scripts engine chips).  They need their own drivers

 * because they are missing so many of the scripts and snazzy register

 * features of their elder brothers (the 710, 720 and 770).

 *

 * The 700 is the lowliest of the line, it can only do async SCSI.

 * The 700-66 can at least do synchronous SCSI up to 10MHz.

 * 

 * The 700 chip has no host bus interface logic of its own.  However,

 * it is usually mapped to a location with well defined register

 * offsets.  Therefore, if you can determine the base address and the

 * irq your board incorporating this chip uses, you can probably use

 * this driver to run it (although you'll probably have to write a

 * minimal wrapper for the purpose---see the NCR_D700 driver for

 * details about how to do this).

 *

 *

 * TODO List:

 *

 * 1. Better statistics in the proc fs

 *

 * 2. Implement message queue (queues SCSI messages like commands) and make

 *    the abort and device reset functions use them.

 * */

​

/* CHANGELOG

 *

 * Version 2.8

 *

 * Fixed bad bug affecting tag starvation processing (previously the

 * driver would hang the system if too many tags starved.  Also fixed

 * bad bug having to do with 10 byte command processing and REQUEST

 * SENSE (the command would loop forever getting a transfer length

 * mismatch in the CMD phase).

 *

 * Version 2.7

 *

 * Fixed scripts problem which caused certain devices (notably CDRWs)

 * to hang on initial INQUIRY.  Updated NCR_700_readl/writel to use

 * __raw_readl/writel for parisc compatibility (Thomas

 * Bogendoerfer). Added missing SCp->request_bufflen initialisation

 * for sense requests (Ryan Bradetich).

 *

 * Version 2.6

 *

 * Following test of the 64 bit parisc kernel by Richard Hirst,

 * several problems have now been corrected.  Also adds support for

 * consistent memory allocation.

 *

 * Version 2.5

 * 

 * More Compatibility changes for 710 (now actually works).  Enhanced

 * support for odd clock speeds which constrain SDTR negotiations.

 * correct cacheline separation for scsi messages and status for

 * incoherent architectures.  Use of the pci mapping functions on

 * buffers to begin support for 64 bit drivers.

 *

 * Version 2.4

 *

 * Added support for the 53c710 chip (in 53c700 emulation mode only---no 

 * special 53c710 instructions or registers are used).

 *

 * Version 2.3

 *

 * More endianness/cache coherency changes.

 *