andrius
/
arm-trusted-firmware
1
0
Fork 0
Code Issues Pull Requests Releases Wiki Activity

plat/arm: Support direct Linux kernel boot in AArch32 

This option allows the Trusted Firmware to directly jump to Linux
kernel for aarch32 without the need of an intermediate loader such
as U-Boot.

Similar to AArch64 ARM_LINUX_KERNEL_AS_BL33 only available with
RESET_TO_SP_MIN=1 as well as BL33 and DTB are preloaded in memory.

Change-Id: I908bc1633696be1caad0ce2f099c34215c8e0633
Signed-off-by: Manish Pandey <manish.pandey2@arm.com>
This commit is contained in:
Manish Pandey 2018-11-02 13:28:25 +00:00
parent dd756c9895
commit ed2c4f4a44
4 changed files with 29 additions and 10 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

2
bl32/sp_min/sp_min_main.c
View File

@ -101,6 +101,8 @@ static void copy_cpu_ctx_to_smc_stx(const regs_t *cpu_reg_ctx,
smc_ctx_t *next_smc_ctx)
{
next_smc_ctx->r0 = read_ctx_reg(cpu_reg_ctx, CTX_GPREG_R0);
next_smc_ctx->r1 = read_ctx_reg(cpu_reg_ctx, CTX_GPREG_R1);
next_smc_ctx->r2 = read_ctx_reg(cpu_reg_ctx, CTX_GPREG_R2);
next_smc_ctx->lr_mon = read_ctx_reg(cpu_reg_ctx, CTX_LR);
next_smc_ctx->spsr_mon = read_ctx_reg(cpu_reg_ctx, CTX_SPSR);
next_smc_ctx->scr = read_ctx_reg(cpu_reg_ctx, CTX_SCR);

11
docs/user-guide.rst
View File

@ -728,11 +728,12 @@ Arm development platform specific build options
- ``ARM_LINUX_KERNEL_AS_BL33``: The Linux kernel expects registers x0-x3 to
have specific values at boot. This boolean option allows the Trusted Firmware
to have a Linux kernel image as BL33 by preparing the registers to these
values before jumping to BL33. This option defaults to 0 (disabled). For now,
it only supports AArch64 kernels. ``RESET_TO_BL31`` must be 1 when using it.
If this option is set to 1, ``ARM_PRELOADED_DTB_BASE`` must be set to the
location of a device tree blob (DTB) already loaded in memory. The Linux
Image address must be specified using the ``PRELOADED_BL33_BASE`` option.
values before jumping to BL33. This option defaults to 0 (disabled). For
AArch64 ``RESET_TO_BL31`` and for AArch32 ``RESET_TO_SP_MIN`` must be 1 when
using it. If this option is set to 1, ``ARM_PRELOADED_DTB_BASE`` must be set
to the location of a device tree blob (DTB) already loaded in memory. The
Linux Image address must be specified using the ``PRELOADED_BL33_BASE``
option.
- ``ARM_RECOM_STATE_ID_ENC``: The PSCI1.0 specification recommends an encoding
for the construction of composite state-ID in the power-state parameter.

13
plat/arm/common/arm_common.mk
View File

@ -86,11 +86,14 @@ $(eval $(call assert_boolean,ARM_LINUX_KERNEL_AS_BL33))
$(eval $(call add_define,ARM_LINUX_KERNEL_AS_BL33))
ifeq (${ARM_LINUX_KERNEL_AS_BL33},1)
ifneq (${ARCH},aarch64)
$(error "ARM_LINUX_KERNEL_AS_BL33 is only available in AArch64.")
endif
ifneq (${RESET_TO_BL31},1)
$(error "ARM_LINUX_KERNEL_AS_BL33 is only available if RESET_TO_BL31=1.")
ifeq (${ARCH},aarch64)
ifneq (${RESET_TO_BL31},1)
$(error "ARM_LINUX_KERNEL_AS_BL33 is only available if RESET_TO_BL31=1.")
endif
else
ifneq (${RESET_TO_SP_MIN},1)
$(error "ARM_LINUX_KERNEL_AS_BL33 is only available if RESET_TO_SP_MIN=1.")
endif
endif
ifndef PRELOADED_BL33_BASE
$(error "PRELOADED_BL33_BASE must be set if ARM_LINUX_KERNEL_AS_BL33 is used.")

13
plat/arm/common/sp_min/arm_sp_min_setup.c
View File

@ -82,6 +82,19 @@ void arm_sp_min_early_platform_setup(void *from_bl2, uintptr_t tos_fw_config,
bl33_image_ep_info.spsr = arm_get_spsr_for_bl33_entry();
SET_SECURITY_STATE(bl33_image_ep_info.h.attr, NON_SECURE);
# if ARM_LINUX_KERNEL_AS_BL33
/*
* According to the file ``Documentation/arm/Booting`` of the Linux
* kernel tree, Linux expects:
* r0 = 0
* r1 = machine type number, optional in DT-only platforms (~0 if so)
* r2 = Physical address of the device tree blob
*/
bl33_image_ep_info.args.arg0 = 0U;
bl33_image_ep_info.args.arg1 = ~0U;
bl33_image_ep_info.args.arg2 = (u_register_t)ARM_PRELOADED_DTB_BASE;
# endif
#else /* RESET_TO_SP_MIN */
/*