[PATCH] tidy AMD 768MPX fix

[PATCH] tidy AMD 768MPX fix

[Andy Whitcroft]

Convert the AMD 768MPX errata #56 fix to use PAGE_SIZE instead of using
4096 in line with other declarations in this file.  Also take the
oppotunity to match indentation.

Revision: $Rev: 612 $

Signed-off-by: Andy Whitcroft <apw@shadowen.org>

diffstat 020-tidy-AMD-768MPX-fix
---
 setup.c |   10 ++++++----
 1 files changed, 6 insertions(+), 4 deletions(-)

diff -X /home/apw/brief/lib/vdiff.excl -rupN reference/arch/i386/kernel/setup.c current/arch/i386/kernel/setup.c
--- reference/arch/i386/kernel/setup.c	2004-09-02 18:05:57.000000000 +0100
+++ current/arch/i386/kernel/setup.c	2004-09-03 16:59:45.000000000 +0100
@@ -1052,12 +1052,14 @@ static unsigned long __init setup_memory
 	/* reserve EBDA region, it's a 4K region */
 	reserve_ebda_region();
 
-    /* could be an AMD 768MPX chipset. Reserve a page  before VGA to prevent
-       PCI prefetch into it (errata #56). Usually the page is reserved anyways,
-       unless you have no PS/2 mouse plugged in. */
+	/*
+	 * could be an AMD 768MPX chipset. Reserve a page before VGA to
+	 * prevent PCI prefetch into it (errata #56). Usually the page is
+	 * reserved anyways, unless you have no PS/2 mouse plugged in.
+	 */
 	if (boot_cpu_data.x86_vendor == X86_VENDOR_AMD &&
 	    boot_cpu_data.x86 == 6)
-	     reserve_bootmem(0xa0000 - 4096, 4096);
+		reserve_bootmem(0xa0000 - PAGE_SIZE, PAGE_SIZE);
 
 #ifdef CONFIG_SMP
 	/*

Re: [PATCH] tidy AMD 768MPX fix

[Alan Cox]

On Gwe, 2004-09-03 at 17:13, Andy Whitcroft wrote:
> Convert the AMD 768MPX errata #56 fix to use PAGE_SIZE instead of using
> 4096 in line with other declarations in this file.  Also take the
> oppotunity to match indentation.

Even if we use a different software page size in some future x86 release
the workaround is to reserve 4096 bytes. I don't think this change makes
sense therefore.

Re: [PATCH] tidy AMD 768MPX fix

[Andy Whitcroft]

> Even if we use a different software page size in some future x86 release
> the workaround is to reserve 4096 bytes. I don't think this change makes
> sense therefore.

I have always assumed that PAGE_SIZE in the bootmem allocator was
hardware page size; such that if software PAGE_SIZE was to change that
it would necessarily be replaced with two different constants.  But fair
enough.  In that case perhaps we should at least fix the code indent
etc.  Revised patch below.

-apw

=== 8< ===
Fix indentation and layout of AMD 768MPX errata #56 fix.

Revision: $Rev: 620 $

Signed-off-by: Andy Whitcroft <apw@shadowen.org>

diffstat 020-tidy-AMD-768MPX-fix
---
 setup.c |   10 ++++++----
 1 files changed, 6 insertions(+), 4 deletions(-)

diff -X /home/apw/brief/lib/vdiff.excl -rupN reference/arch/i386/kernel/setup.c current/arch/i386/kernel/setup.c
--- reference/arch/i386/kernel/setup.c	2004-09-02 18:05:57.000000000 +0100
+++ current/arch/i386/kernel/setup.c	2004-09-03 17:34:58.000000000 +0100
@@ -1052,12 +1052,14 @@ static unsigned long __init setup_memory
 	/* reserve EBDA region, it's a 4K region */
 	reserve_ebda_region();
 
-    /* could be an AMD 768MPX chipset. Reserve a page  before VGA to prevent
-       PCI prefetch into it (errata #56). Usually the page is reserved anyways,
-       unless you have no PS/2 mouse plugged in. */
+	/*
+	 * could be an AMD 768MPX chipset. Reserve a page before VGA to
+	 * prevent PCI prefetch into it (errata #56). Usually the page is
+	 * reserved anyways, unless you have no PS/2 mouse plugged in.
+	 */
 	if (boot_cpu_data.x86_vendor == X86_VENDOR_AMD &&
 	    boot_cpu_data.x86 == 6)
-	     reserve_bootmem(0xa0000 - 4096, 4096);
+		reserve_bootmem(0xa0000 - 4096, 4096);
 
 #ifdef CONFIG_SMP
 	/*

Re: [PATCH] tidy AMD 768MPX fix

[David Woodhouse]

On Fri, 2004-09-03 at 17:46 +0100, Andy Whitcroft wrote:
>   In that case perhaps we should at least fix the code indent
> etc.  Revised patch below.

If it's only a cosmetic patch anyway, it seems silly to do it without
also fixing the misspelling of 'erratum' :)

-- 
dwmw2