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treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 500 Based on 2 normalized pattern(s): this program is free software you can redistribute it and or modify it under the terms of the gnu general public license version 2 as published by the free software foundation this program is free software you can redistribute it and or modify it under the terms of the gnu general public license version 2 as published by the free software foundation # extracted by the scancode license scanner the SPDX license identifier GPL-2.0-only has been chosen to replace the boilerplate/reference in 4122 file(s). Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Enrico Weigelt <info@metux.net> Reviewed-by: Kate Stewart <kstewart@linuxfoundation.org> Reviewed-by: Allison Randal <allison@lohutok.net> Cc: linux-spdx@vger.kernel.org Link: https://lkml.kernel.org/r/20190604081206.933168790@linutronix.de Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-06-04 16:11:33 +08:00
/* SPDX-License-Identifier: GPL-2.0-only */
ARC: Boot #1: low-level, setup_arch(), /proc/cpuinfo, mem init Signed-off-by: Vineet Gupta <vgupta@synopsys.com> Acked-by: Arnd Bergmann <arnd@arndb.de>
2013-01-18 17:42:20 +08:00
/*
* ARC CPU startup Code
*
* Copyright (C) 2004, 2007-2010, 2011-2012 Synopsys, Inc. (www.synopsys.com)
*
* Vineetg: Dec 2007
* -Check if we are running on Simulator or on real hardware
* to skip certain things during boot on simulator
*/
ARC: Disable caches in early boot if so configured Requested-by: Noam Camus <noamc@ezchip.com> Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
2014-03-07 20:38:11 +08:00
#include <linux/linkage.h>
ARC: Boot #1: low-level, setup_arch(), /proc/cpuinfo, mem init Signed-off-by: Vineet Gupta <vgupta@synopsys.com> Acked-by: Arnd Bergmann <arnd@arndb.de>
2013-01-18 17:42:20 +08:00
#include <asm/asm-offsets.h>
#include <asm/entry.h>
#include <asm/arcregs.h>
ARC: Disable caches in early boot if so configured Requested-by: Noam Camus <noamc@ezchip.com> Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
2014-03-07 20:38:11 +08:00
#include <asm/cache.h>
ARC: handle DSP presence in HW When DSP extensions are present, some of the regular integer instructions such as DIV, MACD etc are executed in the DSP unit with semantics alterable by flags in DSP_CTRL aux register. This register is writable by userspace and thus can potentially affect corresponding instructions in kernel code, intentionally or otherwise. So safegaurd kernel by effectively disabling DSP_CTRL upon bootup and every entry to kernel. Do note that for this config we simply zero out the DSP_CTRL reg assuming userspace doesn't really care about DSP. The next patch caters to the DSP aware userspace where this reg is saved/restored upon kernel entry/exit. Reviewed-by: Vineet Gupta <vgupta@synopsys.com> Signed-off-by: Eugeniy Paltsev <Eugeniy.Paltsev@synopsys.com> Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
2020-03-06 04:02:50 +08:00
#include <asm/dsp-impl.h>
ARCv2: Enable unaligned access in early ASM code It is currently done in arc_init_IRQ() which might be too late considering gcc 7.3.1 onwards (GNU 2018.03) generates unaligned memory accesses by default Cc: stable@vger.kernel.org #4.4+ Signed-off-by: Eugeniy Paltsev <Eugeniy.Paltsev@synopsys.com> Signed-off-by: Vineet Gupta <vgupta@synopsys.com> [vgupta: rewrote changelog]
2019-01-16 19:29:50 +08:00
#include <asm/irqflags.h>
ARC: Disable caches in early boot if so configured Requested-by: Noam Camus <noamc@ezchip.com> Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
2014-03-07 20:38:11 +08:00
.macro CPU_EARLY_SETUP
; Setting up Vectror Table (in case exception happens in early boot
sr @_int_vec_base_lds, [AUX_INTR_VEC_BASE]
; Disable I-cache/D-cache if kernel so configured
lr r5, [ARC_REG_IC_BCR]
breq r5, 0, 1f ; I$ doesn't exist
lr r5, [ARC_REG_IC_CTRL]
#ifdef CONFIG_ARC_HAS_ICACHE
bclr r5, r5, 0 ; 0 - Enable, 1 is Disable
#else
bset r5, r5, 0 ; I$ exists, but is not used
#endif
sr r5, [ARC_REG_IC_CTRL]
1:
lr r5, [ARC_REG_DC_BCR]
breq r5, 0, 1f ; D$ doesn't exist
lr r5, [ARC_REG_DC_CTRL]
bclr r5, r5, 6 ; Invalidate (discard w/o wback)
#ifdef CONFIG_ARC_HAS_DCACHE
bclr r5, r5, 0 ; Enable (+Inv)
#else
bset r5, r5, 0 ; Disable (+Inv)
#endif
sr r5, [ARC_REG_DC_CTRL]
1:
ARCv2: Enable unaligned access in early ASM code It is currently done in arc_init_IRQ() which might be too late considering gcc 7.3.1 onwards (GNU 2018.03) generates unaligned memory accesses by default Cc: stable@vger.kernel.org #4.4+ Signed-off-by: Eugeniy Paltsev <Eugeniy.Paltsev@synopsys.com> Signed-off-by: Vineet Gupta <vgupta@synopsys.com> [vgupta: rewrote changelog]
2019-01-16 19:29:50 +08:00
#ifdef CONFIG_ISA_ARCV2
; Unaligned access is disabled at reset, so re-enable early as
; gcc 7.3.1 (ARC GNU 2018.03) onwards generates unaligned access
; by default
lr r5, [status32]
ARCv2: Add explcit unaligned access support (and ability to disable too) As of today we enable unaligned access unconditionally on ARCv2. Do this under a Kconfig option to allow disable it for test, benchmarking etc. Also while at it - Select HAVE_EFFICIENT_UNALIGNED_ACCESS - Although gcc defaults to unaligned access (since GNU 2018.03), add the right toggles for enabling or disabling as appropriate - update bootlog to prints both HW feature status (exists, enabled/disabled) and SW status (used / not used). - wire up the relaxed memcpy for unaligned access Signed-off-by: Eugeniy Paltsev <Eugeniy.Paltsev@synopsys.com> Signed-off-by: Vineet Gupta <vgupta@synopsys.com> [vgupta: squashed patches, handle gcc -mno-unaligned-access quick]
2019-01-31 00:32:41 +08:00
#ifdef CONFIG_ARC_USE_UNALIGNED_MEM_ACCESS
ARCv2: Enable unaligned access in early ASM code It is currently done in arc_init_IRQ() which might be too late considering gcc 7.3.1 onwards (GNU 2018.03) generates unaligned memory accesses by default Cc: stable@vger.kernel.org #4.4+ Signed-off-by: Eugeniy Paltsev <Eugeniy.Paltsev@synopsys.com> Signed-off-by: Vineet Gupta <vgupta@synopsys.com> [vgupta: rewrote changelog]
2019-01-16 19:29:50 +08:00
bset r5, r5, STATUS_AD_BIT
ARCv2: Add explcit unaligned access support (and ability to disable too) As of today we enable unaligned access unconditionally on ARCv2. Do this under a Kconfig option to allow disable it for test, benchmarking etc. Also while at it - Select HAVE_EFFICIENT_UNALIGNED_ACCESS - Although gcc defaults to unaligned access (since GNU 2018.03), add the right toggles for enabling or disabling as appropriate - update bootlog to prints both HW feature status (exists, enabled/disabled) and SW status (used / not used). - wire up the relaxed memcpy for unaligned access Signed-off-by: Eugeniy Paltsev <Eugeniy.Paltsev@synopsys.com> Signed-off-by: Vineet Gupta <vgupta@synopsys.com> [vgupta: squashed patches, handle gcc -mno-unaligned-access quick]
2019-01-31 00:32:41 +08:00
#else
; Although disabled at reset, bootloader might have enabled it
bclr r5, r5, STATUS_AD_BIT
#endif
ARCv2: Enable unaligned access in early ASM code It is currently done in arc_init_IRQ() which might be too late considering gcc 7.3.1 onwards (GNU 2018.03) generates unaligned memory accesses by default Cc: stable@vger.kernel.org #4.4+ Signed-off-by: Eugeniy Paltsev <Eugeniy.Paltsev@synopsys.com> Signed-off-by: Vineet Gupta <vgupta@synopsys.com> [vgupta: rewrote changelog]
2019-01-16 19:29:50 +08:00
kflag r5
#endif
ARC: handle DSP presence in HW When DSP extensions are present, some of the regular integer instructions such as DIV, MACD etc are executed in the DSP unit with semantics alterable by flags in DSP_CTRL aux register. This register is writable by userspace and thus can potentially affect corresponding instructions in kernel code, intentionally or otherwise. So safegaurd kernel by effectively disabling DSP_CTRL upon bootup and every entry to kernel. Do note that for this config we simply zero out the DSP_CTRL reg assuming userspace doesn't really care about DSP. The next patch caters to the DSP aware userspace where this reg is saved/restored upon kernel entry/exit. Reviewed-by: Vineet Gupta <vgupta@synopsys.com> Signed-off-by: Eugeniy Paltsev <Eugeniy.Paltsev@synopsys.com> Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
2020-03-06 04:02:50 +08:00
; Config DSP_CTRL properly, so kernel may use integer multiply,
; multiply-accumulate, and divide operations
DSP_EARLY_INIT
ARC: Disable caches in early boot if so configured Requested-by: Noam Camus <noamc@ezchip.com> Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
2014-03-07 20:38:11 +08:00
.endm
ARC: Boot #1: low-level, setup_arch(), /proc/cpuinfo, mem init Signed-off-by: Vineet Gupta <vgupta@synopsys.com> Acked-by: Arnd Bergmann <arnd@arndb.de>
2013-01-18 17:42:20 +08:00
.section .init.text, "ax",@progbits
ARC: boot: Support Halt-on-reset and Run-on-reset SMP booting modes For Run-on-reset, non masters need to spin wait. For Halt-on-reset they can jump to entry point directly. Also while at it, made reset vector handler as "the" entry point for kernel including host debugger based boot (which uses the ELF header entry point) Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
2015-10-09 13:56:12 +08:00
;----------------------------------------------------------------
; Default Reset Handler (jumped into from Reset vector)
; - Don't clobber r0,r1,r2 as they might have u-boot provided args
; - Platforms can override this weak version if needed
;----------------------------------------------------------------
WEAK(res_service)
j stext
END(res_service)
;----------------------------------------------------------------
; Kernel Entry point
;----------------------------------------------------------------
ENTRY(stext)
ARC: Boot #1: low-level, setup_arch(), /proc/cpuinfo, mem init Signed-off-by: Vineet Gupta <vgupta@synopsys.com> Acked-by: Arnd Bergmann <arnd@arndb.de>
2013-01-18 17:42:20 +08:00
ARC: Disable caches in early boot if so configured Requested-by: Noam Camus <noamc@ezchip.com> Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
2014-03-07 20:38:11 +08:00
CPU_EARLY_SETUP
ARC: Setup Vector Table Base in early boot Otherwise early boot exceptions such as instructions errors due to configuration mismatch between kernel and hardware go off to la-la land, as opposed to hitting the handler and panic()'ing properly. Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
2013-06-17 20:57:23 +08:00
ARC: SMP support ARC common code to enable a SMP system + ISS provided SMP extensions. ARC700 natively lacks SMP support, hence some of the core features are are only enabled if SoCs have the necessary h/w pixie-dust. This includes: -Inter Processor Interrupts (IPI) -Cache coherency -load-locked/store-conditional ... The low level exception handling would be completely broken in SMP because we don't have hardware assisted stack switching. Thus a fair bit of this code is repurposing the MMU_SCRATCH reg for event handler prologues to keep them re-entrant. Many thanks to Rajeshwar Ranga for his initial "major" contributions to SMP Port (back in 2008), and to Noam Camus and Gilad Ben-Yossef for help with resurrecting that in 3.2 kernel (2012). Note that this platform code is again singleton design pattern - so multiple SMP platforms won't build at the moment - this deficiency is addressed in subsequent patches within this series. Signed-off-by: Vineet Gupta <vgupta@synopsys.com> Cc: Arnd Bergmann <arnd@arndb.de> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Rajeshwar Ranga <rajeshwar.ranga@gmail.com> Cc: Noam Camus <noamc@ezchip.com> Cc: Gilad Ben-Yossef <gilad@benyossef.com>
2013-01-18 17:42:23 +08:00
#ifdef CONFIG_SMP
GET_CPU_ID r5
cmp r5, 0
ARC: boot: Support Halt-on-reset and Run-on-reset SMP booting modes For Run-on-reset, non masters need to spin wait. For Halt-on-reset they can jump to entry point directly. Also while at it, made reset vector handler as "the" entry point for kernel including host debugger based boot (which uses the ELF header entry point) Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
2015-10-09 13:56:12 +08:00
mov.nz r0, r5
ARC: smp-boot: Decouple Non masters waiting API from jump to entry point For run-on-reset SMP configs, non master cores call a routine which waits until Master gives it a "go" signal (currently using a shared mem flag). The same routine then jumps off the well known entry point of all non Master cores i.e. @first_lines_of_secondary This patch moves out the last part into one single place in early boot code. This is better in terms of absraction (the wait API only waits) and returns, leaving out the "jump off to" part. In actual implementation this requires some restructuring of the early boot code as well as Master now jumps to BSS setup explicitly, vs. falling thru into it before. Technically this patch doesn't cause any functional change, it just moves the ugly #ifdef'ry from assembly code to "C" Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
2017-01-13 06:30:29 +08:00
bz .Lmaster_proceed
ARC: boot: Support Halt-on-reset and Run-on-reset SMP booting modes For Run-on-reset, non masters need to spin wait. For Halt-on-reset they can jump to entry point directly. Also while at it, made reset vector handler as "the" entry point for kernel including host debugger based boot (which uses the ELF header entry point) Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
2015-10-09 13:56:12 +08:00
; Non-Masters wait for Master to boot enough and bring them up
ARC: smp-boot: Decouple Non masters waiting API from jump to entry point For run-on-reset SMP configs, non master cores call a routine which waits until Master gives it a "go" signal (currently using a shared mem flag). The same routine then jumps off the well known entry point of all non Master cores i.e. @first_lines_of_secondary This patch moves out the last part into one single place in early boot code. This is better in terms of absraction (the wait API only waits) and returns, leaving out the "jump off to" part. In actual implementation this requires some restructuring of the early boot code as well as Master now jumps to BSS setup explicitly, vs. falling thru into it before. Technically this patch doesn't cause any functional change, it just moves the ugly #ifdef'ry from assembly code to "C" Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
2017-01-13 06:30:29 +08:00
; when they resume, tail-call to entry point
mov blink, @first_lines_of_secondary
j arc_platform_smp_wait_to_boot
.Lmaster_proceed:
ARC: SMP support ARC common code to enable a SMP system + ISS provided SMP extensions. ARC700 natively lacks SMP support, hence some of the core features are are only enabled if SoCs have the necessary h/w pixie-dust. This includes: -Inter Processor Interrupts (IPI) -Cache coherency -load-locked/store-conditional ... The low level exception handling would be completely broken in SMP because we don't have hardware assisted stack switching. Thus a fair bit of this code is repurposing the MMU_SCRATCH reg for event handler prologues to keep them re-entrant. Many thanks to Rajeshwar Ranga for his initial "major" contributions to SMP Port (back in 2008), and to Noam Camus and Gilad Ben-Yossef for help with resurrecting that in 3.2 kernel (2012). Note that this platform code is again singleton design pattern - so multiple SMP platforms won't build at the moment - this deficiency is addressed in subsequent patches within this series. Signed-off-by: Vineet Gupta <vgupta@synopsys.com> Cc: Arnd Bergmann <arnd@arndb.de> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Rajeshwar Ranga <rajeshwar.ranga@gmail.com> Cc: Noam Camus <noamc@ezchip.com> Cc: Gilad Ben-Yossef <gilad@benyossef.com>
2013-01-18 17:42:23 +08:00
#endif
ARC: boot: Support Halt-on-reset and Run-on-reset SMP booting modes For Run-on-reset, non masters need to spin wait. For Halt-on-reset they can jump to entry point directly. Also while at it, made reset vector handler as "the" entry point for kernel including host debugger based boot (which uses the ELF header entry point) Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
2015-10-09 13:56:12 +08:00
ARC: Boot #1: low-level, setup_arch(), /proc/cpuinfo, mem init Signed-off-by: Vineet Gupta <vgupta@synopsys.com> Acked-by: Arnd Bergmann <arnd@arndb.de>
2013-01-18 17:42:20 +08:00
; Clear BSS before updating any globals
; XXX: use ZOL here
mov r5, __bss_start
ARC: optimize kernel bss clearing in early boot code using ARC ZOL which reduces tot num of instructions by half Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
2014-04-17 19:43:26 +08:00
sub r6, __bss_stop, r5
lsr.f lp_count, r6, 2
lpnz 1f
st.ab 0, [r5, 4]
ARC: Boot #1: low-level, setup_arch(), /proc/cpuinfo, mem init Signed-off-by: Vineet Gupta <vgupta@synopsys.com> Acked-by: Arnd Bergmann <arnd@arndb.de>
2013-01-18 17:42:20 +08:00
1:
ARC: [cmdline] uboot cmdline handling rework * Moved cmdline copy from asm to "C" - allows for more robust checking of pointer validity etc. * Remove the Kconfig option to do so, base it on a runtime value passed by u-boot Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
2014-01-16 17:31:24 +08:00
; Uboot - kernel ABI
; r0 = [0] No uboot interaction, [1] cmdline in r2, [2] DTB in r2
ARC: U-boot: check arguments paranoidly Handle U-boot arguments paranoidly: * don't allow to pass unknown tag. * try to use external device tree blob only if corresponding tag (TAG_DTB) is set. * don't check uboot_tag if kernel build with no ARC_UBOOT_SUPPORT. NOTE: If U-boot args are invalid we skip them and try to use embedded device tree blob. We can't panic on invalid U-boot args as we really pass invalid args due to bug in U-boot code. This happens if we don't provide external DTB to U-boot and don't set 'bootargs' U-boot environment variable (which is default case at least for HSDK board) In that case we will pass {r0 = 1 (bootargs in r2); r1 = 0; r2 = 0;} to linux which is invalid. While I'm at it refactor U-boot arguments handling code. Cc: stable@vger.kernel.org Tested-by: Corentin LABBE <clabbe@baylibre.com> Signed-off-by: Eugeniy Paltsev <Eugeniy.Paltsev@synopsys.com> Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
2019-02-14 23:07:44 +08:00
; r1 = magic number (always zero as of now)
ARC: [cmdline] uboot cmdline handling rework * Moved cmdline copy from asm to "C" - allows for more robust checking of pointer validity etc. * Remove the Kconfig option to do so, base it on a runtime value passed by u-boot Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
2014-01-16 17:31:24 +08:00
; r2 = pointer to uboot provided cmdline or external DTB in mem
ARC: U-boot: check arguments paranoidly Handle U-boot arguments paranoidly: * don't allow to pass unknown tag. * try to use external device tree blob only if corresponding tag (TAG_DTB) is set. * don't check uboot_tag if kernel build with no ARC_UBOOT_SUPPORT. NOTE: If U-boot args are invalid we skip them and try to use embedded device tree blob. We can't panic on invalid U-boot args as we really pass invalid args due to bug in U-boot code. This happens if we don't provide external DTB to U-boot and don't set 'bootargs' U-boot environment variable (which is default case at least for HSDK board) In that case we will pass {r0 = 1 (bootargs in r2); r1 = 0; r2 = 0;} to linux which is invalid. While I'm at it refactor U-boot arguments handling code. Cc: stable@vger.kernel.org Tested-by: Corentin LABBE <clabbe@baylibre.com> Signed-off-by: Eugeniy Paltsev <Eugeniy.Paltsev@synopsys.com> Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
2019-02-14 23:07:44 +08:00
; These are handled later in handle_uboot_args()
ARC: [cmdline] uboot cmdline handling rework * Moved cmdline copy from asm to "C" - allows for more robust checking of pointer validity etc. * Remove the Kconfig option to do so, base it on a runtime value passed by u-boot Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
2014-01-16 17:31:24 +08:00
st r0, [@uboot_tag]
ARC: u-boot args: check that magic number is correct In case of devboards we really often disable bootloader and load Linux image in memory via JTAG. Even if kernel tries to verify uboot_tag and uboot_arg there is sill a chance that we treat some garbage in registers as valid u-boot arguments in JTAG case. E.g. it is enough to have '1' in r0 to treat any value in r2 as a boot command line. So check that magic number passed from u-boot is correct and drop u-boot arguments otherwise. That helps to reduce the possibility of using garbage as u-boot arguments in JTAG case. We can safely check U-boot magic value (0x0) in linux passed via r1 register as U-boot pass it from the beginning. So there is no backward-compatibility issues. Signed-off-by: Eugeniy Paltsev <Eugeniy.Paltsev@synopsys.com> Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
2019-02-26 01:16:01 +08:00
st r1, [@uboot_magic]
ARC: [cmdline] uboot cmdline handling rework * Moved cmdline copy from asm to "C" - allows for more robust checking of pointer validity etc. * Remove the Kconfig option to do so, base it on a runtime value passed by u-boot Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
2014-01-16 17:31:24 +08:00
st r2, [@uboot_arg]
ARC: Boot #1: low-level, setup_arch(), /proc/cpuinfo, mem init Signed-off-by: Vineet Gupta <vgupta@synopsys.com> Acked-by: Arnd Bergmann <arnd@arndb.de>
2013-01-18 17:42:20 +08:00
; setup "current" tsk and optionally cache it in dedicated r25
mov r9, @init_task
SET_CURR_TASK_ON_CPU r9, r0 ; r9 = tsk, r0 = scratch
; setup stack (fp, sp)
mov fp, 0
; tsk->thread_info is really a PAGE, whose bottom hoists stack
GET_TSK_STACK_BASE r9, sp ; r9 = tsk, sp = stack base(output)
j start_kernel ; "C" entry point
ARC: boot: Support Halt-on-reset and Run-on-reset SMP booting modes For Run-on-reset, non masters need to spin wait. For Halt-on-reset they can jump to entry point directly. Also while at it, made reset vector handler as "the" entry point for kernel including host debugger based boot (which uses the ELF header entry point) Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
2015-10-09 13:56:12 +08:00
END(stext)
ARC: SMP support ARC common code to enable a SMP system + ISS provided SMP extensions. ARC700 natively lacks SMP support, hence some of the core features are are only enabled if SoCs have the necessary h/w pixie-dust. This includes: -Inter Processor Interrupts (IPI) -Cache coherency -load-locked/store-conditional ... The low level exception handling would be completely broken in SMP because we don't have hardware assisted stack switching. Thus a fair bit of this code is repurposing the MMU_SCRATCH reg for event handler prologues to keep them re-entrant. Many thanks to Rajeshwar Ranga for his initial "major" contributions to SMP Port (back in 2008), and to Noam Camus and Gilad Ben-Yossef for help with resurrecting that in 3.2 kernel (2012). Note that this platform code is again singleton design pattern - so multiple SMP platforms won't build at the moment - this deficiency is addressed in subsequent patches within this series. Signed-off-by: Vineet Gupta <vgupta@synopsys.com> Cc: Arnd Bergmann <arnd@arndb.de> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Rajeshwar Ranga <rajeshwar.ranga@gmail.com> Cc: Noam Camus <noamc@ezchip.com> Cc: Gilad Ben-Yossef <gilad@benyossef.com>
2013-01-18 17:42:23 +08:00
#ifdef CONFIG_SMP
;----------------------------------------------------------------
; First lines of code run by secondary before jumping to 'C'
;----------------------------------------------------------------
arc: remove '__init' for first_lines_of_secondary() first_lines_of_secondary() is a '__init' function, but it may be called by __cpu_up() by _cpu_up() by cpu_up() which is a normal export symbol function. So recommend to remove '__init'. The related warning (with allmodconfig): MODPOST vmlinux.o WARNING: vmlinux.o(.text+0x315c): Section mismatch in reference from the function __cpu_up() to the function .init.text:first_lines_of_secondary() The function __cpu_up() references the function __init first_lines_of_secondary(). This is often because __cpu_up lacks a __init annotation or the annotation of first_lines_of_secondary is wrong. Signed-off-by: Chen Gang <gang.chen@asianux.com>
2013-10-23 10:16:38 +08:00
.section .text, "ax",@progbits
ARC: boot: Support Halt-on-reset and Run-on-reset SMP booting modes For Run-on-reset, non masters need to spin wait. For Halt-on-reset they can jump to entry point directly. Also while at it, made reset vector handler as "the" entry point for kernel including host debugger based boot (which uses the ELF header entry point) Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
2015-10-09 13:56:12 +08:00
ENTRY(first_lines_of_secondary)
ARC: SMP support ARC common code to enable a SMP system + ISS provided SMP extensions. ARC700 natively lacks SMP support, hence some of the core features are are only enabled if SoCs have the necessary h/w pixie-dust. This includes: -Inter Processor Interrupts (IPI) -Cache coherency -load-locked/store-conditional ... The low level exception handling would be completely broken in SMP because we don't have hardware assisted stack switching. Thus a fair bit of this code is repurposing the MMU_SCRATCH reg for event handler prologues to keep them re-entrant. Many thanks to Rajeshwar Ranga for his initial "major" contributions to SMP Port (back in 2008), and to Noam Camus and Gilad Ben-Yossef for help with resurrecting that in 3.2 kernel (2012). Note that this platform code is again singleton design pattern - so multiple SMP platforms won't build at the moment - this deficiency is addressed in subsequent patches within this series. Signed-off-by: Vineet Gupta <vgupta@synopsys.com> Cc: Arnd Bergmann <arnd@arndb.de> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Rajeshwar Ranga <rajeshwar.ranga@gmail.com> Cc: Noam Camus <noamc@ezchip.com> Cc: Gilad Ben-Yossef <gilad@benyossef.com>
2013-01-18 17:42:23 +08:00
; setup per-cpu idle task as "current" on this CPU
ld r0, [@secondary_idle_tsk]
SET_CURR_TASK_ON_CPU r0, r1
; setup stack (fp, sp)
mov fp, 0
; set it's stack base to tsk->thread_info bottom
GET_TSK_STACK_BASE r0, sp
j start_kernel_secondary
ARC: boot: Support Halt-on-reset and Run-on-reset SMP booting modes For Run-on-reset, non masters need to spin wait. For Halt-on-reset they can jump to entry point directly. Also while at it, made reset vector handler as "the" entry point for kernel including host debugger based boot (which uses the ELF header entry point) Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
2015-10-09 13:56:12 +08:00
END(first_lines_of_secondary)
ARC: SMP support ARC common code to enable a SMP system + ISS provided SMP extensions. ARC700 natively lacks SMP support, hence some of the core features are are only enabled if SoCs have the necessary h/w pixie-dust. This includes: -Inter Processor Interrupts (IPI) -Cache coherency -load-locked/store-conditional ... The low level exception handling would be completely broken in SMP because we don't have hardware assisted stack switching. Thus a fair bit of this code is repurposing the MMU_SCRATCH reg for event handler prologues to keep them re-entrant. Many thanks to Rajeshwar Ranga for his initial "major" contributions to SMP Port (back in 2008), and to Noam Camus and Gilad Ben-Yossef for help with resurrecting that in 3.2 kernel (2012). Note that this platform code is again singleton design pattern - so multiple SMP platforms won't build at the moment - this deficiency is addressed in subsequent patches within this series. Signed-off-by: Vineet Gupta <vgupta@synopsys.com> Cc: Arnd Bergmann <arnd@arndb.de> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Rajeshwar Ranga <rajeshwar.ranga@gmail.com> Cc: Noam Camus <noamc@ezchip.com> Cc: Gilad Ben-Yossef <gilad@benyossef.com>
2013-01-18 17:42:23 +08:00
#endif