[PATCH] Reserve only needed regions for PC timers on i386 and x86_64

[Charles-Edouard Ruault <ce@idtect.com>]

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Alan Cox wrote:

>On Llu, 2005-02-07 at 09:29, Charles-Edouard Ruault wrote:
>  
>
>>- Why is the generic timer using this address ? isn't it reserving a too 
>>wide portion of IO ports ? Should it be modified for this board ?
>>    
>>
>
>It just reserved the entire chip space since way back when.
>
>  
>
>>-  If there's a good reason for the timer to request this address, is  
>>there a clean way to share it with the timer ?
>>    
>>
>
>Submit a small patch to Linus/Andrew to make the generic code only
>reserve the ports it should. It's just a historical oversight
>
>  
>
Linus, Andrew,
As suggested by Alan, here's a small patch against kernel 2.4.29 to 
split the IO addresses reserved for the  PC timer into two regions 
instead of a large one.
It mimics what has been done in kernel 2.6.
Instead of reserving 0x40 through 0x5f it reserves only what the two 
timers need, i.e 0x40-0x43 and 0x50-0x53.
It patches both i386 and x86_64 architecture.

Please CC me in replies since i did not subscribe to the list.

-- 
Charles-Edouard Ruault
Idtect SA
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--- linux/arch/i386/kernel/setup.c.orig	Fri Feb 18 18:46:55 2005
+++ linux/arch/i386/kernel/setup.c	Mon Feb 21 11:19:45 2005
@@ -354,7 +354,8 @@
 struct resource standard_io_resources[] = {
 	{ "dma1", 0x00, 0x1f, IORESOURCE_BUSY },
 	{ "pic1", 0x20, 0x3f, IORESOURCE_BUSY },
-	{ "timer", 0x40, 0x5f, IORESOURCE_BUSY },
+	{ "timer0", 0x40, 0x43, IORESOURCE_BUSY },
+	{ "timer1", 0x50, 0x53, IORESOURCE_BUSY },
 	{ "keyboard", 0x60, 0x6f, IORESOURCE_BUSY },
 	{ "dma page reg", 0x80, 0x8f, IORESOURCE_BUSY },
 	{ "pic2", 0xa0, 0xbf, IORESOURCE_BUSY },
--- linux/arch/x86_64/kernel/setup.c.orig	Mon Feb 21 11:56:11 2005
+++ linux/arch/x86_64/kernel/setup.c	Mon Feb 21 11:54:41 2005
@@ -93,7 +93,8 @@
 struct resource standard_io_resources[] = {
 	{ "dma1", 0x00, 0x1f, IORESOURCE_BUSY },
 	{ "pic1", 0x20, 0x3f, IORESOURCE_BUSY },
-	{ "timer", 0x40, 0x5f, IORESOURCE_BUSY },
+	{ "timer0", 0x40, 0x43, IORESOURCE_BUSY },
+	{ "timer1", 0x50, 0x53, IORESOURCE_BUSY },
 	{ "keyboard", 0x60, 0x6f, IORESOURCE_BUSY },
 	{ "dma page reg", 0x80, 0x8f, IORESOURCE_BUSY },
 	{ "pic2", 0xa0, 0xbf, IORESOURCE_BUSY },