From mboxrd@z Thu Jan 1 00:00:00 1970 From: Horms Date: Wed, 07 Feb 2007 06:24:23 +0000 Subject: Re: [PATCH 2/2] [IA64] Add phys_efi command line option Message-Id: <20070207062420.GB29959@verge.net.au> List-Id: MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit To: linux-ia64@vger.kernel.org Hi, I am resending this patch, which builds on the patch sent earlier in this thread to allow physical mode SAL/EFI to work. -- Simon Horman (Horms) horms@verge.net.au http://verge.net.au/~horms/ [IA64] Add phys_efi command line option This patch adds a command line option, phys_efi, which forces EFI calls to stay in physical mode. This is mainly for the purpose of being able to test the physical mode code path. I believe that it may also be needed in order to kexec between OS/hypervisors with different memory layouts, such as Linux->Xen and vice versa, which have 0xe000... and 0xf000... as their page offset respecively. However, I am still working on verifying this. Signed-Off-By: Simon Horman Documentation/kernel-parameters.txt | 4 ++++ arch/ia64/kernel/efi.c | 9 ++++++++- 2 files changed, 12 insertions(+), 1 deletion(-) Index: linux-2.6/arch/ia64/kernel/efi.c =================================--- linux-2.6.orig/arch/ia64/kernel/efi.c 2007-02-07 11:53:10.000000000 +0900 +++ linux-2.6/arch/ia64/kernel/efi.c 2007-02-07 13:14:15.000000000 +0900 @@ -414,6 +414,7 @@ u64 efi_desc_size; char *cp, vendor[100] = "unknown"; extern char saved_command_line[]; + int phys_efi = 0; int i; /* it's too early to be able to use the standard kernel command line support... */ @@ -424,6 +425,9 @@ max_addr = GRANULEROUNDDOWN(memparse(cp + 9, &cp)); } else if (memcmp(cp, "min_addr=", 9) = 0) { min_addr = GRANULEROUNDDOWN(memparse(cp + 9, &cp)); + } else if (memcmp(cp, "phys_efi", 8) = 0) { + phys_efi = 1; + cp+=8; } else { while (*cp != ' ' && *cp) ++cp; @@ -528,7 +532,10 @@ #endif efi_map_pal_code(); - efi_enter_virtual_mode(); + if (phys_efi) + printk("Forcing EFI to stay in physical mode\n"); + else + efi_enter_virtual_mode(); } void Index: linux-2.6/Documentation/kernel-parameters.txt =================================--- linux-2.6.orig/Documentation/kernel-parameters.txt 2007-02-07 11:52:41.000000000 +0900 +++ linux-2.6/Documentation/kernel-parameters.txt 2007-02-07 11:53:11.000000000 +0900 @@ -1276,6 +1276,10 @@ pg. [PARIDE] See Documentation/paride.txt. + phys_efi [IA-64] Force EFI, PAL and SAL calls to be made + in physical mode. Otherwise, if possible virtual mode + calls are made. + pirq= [SMP,APIC] Manual mp-table setup See Documentation/i386/IO-APIC.txt.