netdev - Re: [net-next-2.6 PATCH 2/3] fs_enet: Add support for MPC512x to fs

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Date:	Tue, 09 Feb 2010 12:13:56 -0800 (PST)
From:	David Miller <davem@...emloft.net>
To:	agust@...x.de
Cc:	wg@...ndegger.com, netdev@...r.kernel.org, dzu@...x.de, wd@...x.de,
	jcrigby@...il.com, kosmo@...ihalf.com, linuxppc-dev@...abs.org,
	grant.likely@...retlab.ca
Subject: Re: [net-next-2.6 PATCH 2/3] fs_enet: Add support for MPC512x to
 fs_enet driver

From: Anatolij Gustschin <agust@...x.de>
Date: Tue, 9 Feb 2010 15:23:17 +0100

> In my understanding, in the ESP scsi driver the set of defines for
> the register offsets is common for all chip drivers. The chip driver
> methods for register access translate the offsets because the
> registers on some chips are at different intervals (4-byte, 1-byte,
> 16-byte for mac_esp.c). But the register order is the same for
> different chips.
> 
> In our case non only the register order is not the same for 8xx
> FEC and 5121 FEC, but there are also other differences, different
> reserved areas between several registers, some registers are
> available only on 8xx and some only on 5121.

That only means you would need to use a table based register address
translation scheme, rather than a simple calculation.  Something
like:

static unsigned int chip_xxx_table[] =
{
	[GENERIC_REG_FOO]	 = CHIP_XXX_FOO,
	...
};

static u32 chip_xxx_read_reg(struct chip *p, unsigned int reg)
{
	unsigned int reg_off = chip_xxx_table[reg];

	return readl(p->regs + reg_off);
}

And this table can have special tokens in entries for
registers which do not exist on a chip, so you can trap
attempted access to them in these read/write handlers.

Please stop looking for excuses to fork this driver, a
unified driver I think can be done cleanly.
--
To unsubscribe from this list: send the line "unsubscribe netdev" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html