Revert HPET resource reservation

Matthias Lenk reports that the PCI subsystem would move the HPET on
SB400/SB600-based systems, where the HPET is in BAR1 of the SMbus
controller.

The reason? The ACPI layer registered the PCI MMIO range as being busy
too early, before PCI enumeration had happened, causing the PCI layer to
decide that it should relocate the resources somewhere else.

Firmware resources should be marked busy _after_ the PCI enumeration and
probing has happened, not before.

Remove the too-early reservation, we'll fix it up to do it properly
later.  In the meantime, this solves the regression.

Tested-by: Matthias Lenk <matthias.lenk@amd.com>
Cc: Aaron Durbin <adurbin@google.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

1 files changed, 0 insertions, 19 deletions

diff --git a/arch/i386/kernel/acpi/boot.c b/arch/i386/kernel/acpi/boot.c
index 280898b045b2..3e497fd028e4 100644
--- a/arch/i386/kernel/acpi/boot.c
+++ b/arch/i386/kernel/acpi/boot.c
@@ -636,29 +636,10 @@ static int __init acpi_parse_hpet(struct acpi_table_header *table)
                 return -1;
         }
 
-#define HPET_RESOURCE_NAME_SIZE 9
-        hpet_res = alloc_bootmem(sizeof(*hpet_res) + HPET_RESOURCE_NAME_SIZE);
-        if (hpet_res) {
-                memset(hpet_res, 0, sizeof(*hpet_res));
-                hpet_res->name = (void *)&hpet_res[1];
-                hpet_res->flags = IORESOURCE_MEM | IORESOURCE_BUSY;
-                snprintf((char *)hpet_res->name, HPET_RESOURCE_NAME_SIZE,
-                         "HPET %u", hpet_tbl->sequence);
-                hpet_res->end = (1 * 1024) - 1;
-        }
-
         hpet_address = hpet_tbl->address.address;
         printk(KERN_INFO PREFIX "HPET id: %#x base: %#lx\n",
                hpet_tbl->id, hpet_address);
 
-        res_start = hpet_address;
-
-        if (hpet_res) {
-                hpet_res->start = res_start;
-                hpet_res->end += res_start;
-                insert_resource(&iomem_resource, hpet_res);
-        }
-
         return 0;
 }
 #else