Re: HPET regression in 2.6.26 versus 2.6.25 -- found another user with the same regression

[Yinghai Lu]

On Sun, Aug 24, 2008 at 7:00 PM, David Witbrodt <dawitbro@xxxxxxxxxxxxx> wrote:
>
>
>> after discussing with Ingo, we have one more generic way to detect the
>> same situation.
>>
>> please help to verify the attached patch. ( don't apply previous patch)
>
> Geez, a guy tries to leave so he doesn't get banned because of his stupid
> webmail client, and...  oh, never mind...  ;)
>
>
> Results:
>
> 1) patch applied perfectly to tip/master.
>
> 2) patched file compiles without warning or error.
> (I thought there would be a type mismatch -- the "base" variable in your
> patch is unsigned long, while "res->start" is resource_size_t ==>
> u64 ==> unsigned long long, but I must have been mistaken.)
>
> 3) kernel builds fine
>
> 4) reboot hangs at the familiar call of inet_init()
>

this one should work. please apply this one only.

YH
[PATCH] x86: check hpet with BAR v2

insert some resources to resource tree forcily, so could avoid kernel update the
resources in pci device.

should check in device too.

Signed-off-by: Yinghai Lu <yhlu.kernel@xxxxxxxxx>

---
 arch/x86/pci/i386.c |   43 +++++++++++++++++++++++++++++++++++++++++++
 1 file changed, 43 insertions(+)

Index: linux-2.6/arch/x86/pci/i386.c
===================================================================
--- linux-2.6.orig/arch/x86/pci/i386.c
+++ linux-2.6/arch/x86/pci/i386.c
@@ -33,6 +33,7 @@
 #include <linux/bootmem.h>
 
 #include <asm/pat.h>
+#include <asm/hpet.h>
 
 #include "pci.h"
 
@@ -77,6 +78,30 @@ pcibios_align_resource(void *data, struc
 }
 EXPORT_SYMBOL(pcibios_align_resource);
 
+static int check_res_with_valid(struct pci_dev *dev, struct resource *res)
+{
+	unsigned long base;
+	unsigned long size;
+
+	base = res->start;
+	size = (res->start == 0 && res->end == res->start) ? 0 :
+		 (res->end - res->start + 1);
+
+	if (!base || !size)
+		return 0;
+
+#ifdef CONFIG_HPET_TIMER
+	/* for hpet */
+	if (base == hpet_address && (res->flags & IORESOURCE_MEM)) {
+		dev_info(&dev->dev, "BAR has HPET at %08lx-%08lx\n",
+				 base, base + size - 1);
+		return 1;
+	}
+#endif
+
+	return 0;
+}
+
 /*
  *  Handle resources of PCI devices.  If the world were perfect, we could
  *  just allocate all the resource regions and do nothing more.  It isn't.
@@ -171,6 +196,22 @@ static void __init pcibios_allocate_reso
 					r->flags, disabled, pass);
 				pr = pci_find_parent_resource(dev, r);
 				if (!pr || request_resource(pr, r) < 0) {
+					if (check_res_with_valid(dev, r)) {
+						struct resource *root = NULL;
+
+						/*
+						 * forcibly insert it into the
+						 * resource tree
+						 */
+						if (r->flags & IORESOURCE_MEM)
+							root = &iomem_resource;
+						else if (r->flags & IORESOURCE_IO)
+							root = &ioport_resource;
+
+						if (root)
+							insert_resource(root, r);
+						continue;
+					}
 					dev_err(&dev->dev, "BAR %d: can't "
 						"allocate resource\n", idx);
 					/* We'll assign a new address later */