From mboxrd@z Thu Jan 1 00:00:00 1970 From: msalter@redhat.com (Mark Salter) Date: Thu, 13 Feb 2014 09:56:15 -0500 Subject: [PATCH 03/22] efi: add helper function to get UEFI params from FDT In-Reply-To: <20140213111637.GE20717@console-pimps.org> References: <1391619853-10601-1-git-send-email-leif.lindholm@linaro.org> <1391619853-10601-4-git-send-email-leif.lindholm@linaro.org> <20140213111637.GE20717@console-pimps.org> Message-ID: <1392303375.2771.28.camel@deneb.redhat.com> To: linux-arm-kernel@lists.infradead.org List-Id: linux-arm-kernel.lists.infradead.org On Thu, 2014-02-13 at 11:17 +0000, Matt Fleming wrote: > On Wed, 05 Feb, at 05:03:54PM, Leif Lindholm wrote: > > From: Mark Salter > > > > ARM and ARM64 architectures use the device tree to pass UEFI parameters > > from stub to kernel. These parameters are things known to the stub but > > not discoverable by the kernel after the stub calls ExitBootSerives(). > > There is a helper function in: > > > > drivers/firmware/efi/fdt.c > > > > which the stub uses to add the UEFI parameters to the device tree. > > This patch adds a complimentary helper function which UEFI runtime > > support may use to retrieve the parameters from the device tree. > > If an architecture wants to use this helper, it should select > > CONFIG_UEFI_PARAMS_FROM_FDT. > > > > Signed-off-by: Mark Salter > > Signed-off-by: Leif Lindholm > > --- > > drivers/firmware/efi/Kconfig | 7 ++++ > > drivers/firmware/efi/efi.c | 79 ++++++++++++++++++++++++++++++++++++++++++ > > include/linux/efi.h | 9 +++++ > > 3 files changed, 95 insertions(+) > > Is there a particular reason this change is being added to > drivers/firmware/efi/efi.c and not drivers/firmware/efi/fdt.c? > drivers/firmware/efi/fdt.c is included by the stub which may or may not be linked into kernel image. This helper is used by runtime services and needs to be built into kernel. --Mark