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Michael Brown 19d3e966d9 [pcnet32] Eliminate redundant register read 
The value of ( ( x & 0x0c00 ) | 0x0c00 ) is always 0x0c00 regardless
of the value of x, and so the read_csr() is redundant.  (There are no
read side effects for this register, according to the datasheet.)

This line of code originated in Linux kernel 2.3.19pre1 as

  a->write_csr(ioaddr, 80, a->read_csr(ioaddr, 80) | 0x0c00);

and was modified in kernel 2.3.41pre4 to read

  a->write_csr(ioaddr, 80, (a->read_csr(ioaddr, 80) & 0x0C00) | 0x0c00);

In the absence of commit messages, the intention of the code is
unclear.  However, the logic resulting in a fixed value of 0x0c00 has
remained unaltered for over 17 years, and can probably be assumed to
have the correct overall result.

Signed-off-by: Michael Brown <mcb30@ipxe.org>
 		2017-03-23 17:43:13 +02:00
contrib [coverity] Add Coverity user model 2017-03-22 16:46:03 +02:00
src [pcnet32] Eliminate redundant register read 2017-03-23 17:43:13 +02:00
.travis.yml [travis] Integrate with Coverity Scan 2017-03-23 10:51:25 +02:00
COPYING [legal] Update GPLv2 licence text 2015-02-26 17:59:53 +00:00
COPYING.GPLv2 [legal] Update GPLv2 licence text 2015-02-26 17:59:53 +00:00
COPYING.UBDL [legal] Add support for the Unmodified Binary Distribution Licence 2015-03-02 12:07:14 +00:00
README [doc] Re-add README file 2010-05-28 00:03:47 +01:00

README 

iPXE README File

Quick start guide:

   cd src
   make

For any more detailed instructions, see http://ipxe.org