The implementation of show_stack will panic with wrong fp:

addr    = *fp++;

because the fp isn't checked properly.

The current implementations of show_stack, wchan and stack_trace
haven't been designed properly, so just deprecate them.

This patch is a reference to riscv's way, all codes are modified from
arm's. The patch is passed with:

 - cat /proc/<pid>/stack
 - cat /proc/<pid>/wchan
 - echo c > /proc/sysrq-trigger
Signed-off-by: NGuo Ren <guoren@linux.alibaba.com>

This patch adds support for uprobes on csky architecture.

Just like kprobe, it support single-step and simulate instructions.
Signed-off-by: NGuo Ren <guoren@linux.alibaba.com>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Steven Rostedt (VMware) <rostedt@goodmis.org>

This patch enable kprobes, kretprobes, ftrace interface. It utilized
software breakpoint and single step debug exceptions, instructions
simulation on csky.

We use USR_BKPT replace origin instruction, and the kprobe handler
prepares an excutable memory slot for out-of-line execution with a
copy of the original instruction being probed. Most of instructions
could be executed by single-step, but some instructions need origin
pc value to execute and we need software simulate these instructions.
Signed-off-by: NGuo Ren <guoren@linux.alibaba.com>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Steven Rostedt (VMware) <rostedt@goodmis.org>

Lockdep is needed by proving the spinlocks and rwlocks. Currently,
we only put trace_hardirqs_on/off with csky_irq and
ret_from_exception.
Signed-off-by: NGuo Ren <guoren@linux.alibaba.com>

Support the gcov function in csky architecture.
Signed-off-by: NMa Jun <majun258@linux.alibaba.com>
Signed-off-by: NGuo Ren <guoren@kernel.org>

This patch implements FTRACE_WITH_REGS for csky, which allows a traced
function's arguments (and some other registers) to be captured into a
struct pt_regs, allowing these to be inspected and/or modified.
Signed-off-by: NGuo Ren <guoren@linux.alibaba.com>

Copied and adapted from vincent's patch, but modified for csky.

ref:
https://lore.kernel.org/linux-riscv/1572919114-3886-3-git-send-email-vincent.chen@sifive.com/raw

Add calls to rseq_signal_deliver(), rseq_handle_notify_resume() and
rseq_syscall() to introduce RSEQ support.

1. Call the rseq_handle_notify_resume() function on return to userspace
   if TIF_NOTIFY_RESUME thread flag is set.

2. Call the rseq_signal_deliver() function to fixup on the pre-signal
   frame when a signal is delivered on top of a restartable sequence
   critical section.

3. Check that system calls are not invoked from within rseq critical
   sections by invoking rseq_signal() from ret_from_syscall(). With
   CONFIG_DEBUG_RSEQ, such behavior results in termination of the
   process with SIGSEGV.
Signed-off-by: NGuo Ren <guoren@linux.alibaba.com>

Needed for kprobes support. Copied and adapted from Patrick's patch,
but it has been modified for csky's pt_regs.

ref:
https://lore.kernel.org/linux-riscv/1572919114-3886-2-git-send-email-vincent.chen@sifive.com/rawSigned-off-by: NGuo Ren <ren_guo@c-sky.com>
Cc: Patrick Staehlin <me@packi.ch>

This is required for clone3 which passes the TLS value through a
struct rather than a register.

Cc: Amanieu d'Antras <amanieu@gmail.com>
Signed-off-by: NGuo Ren <guoren@linux.alibaba.com>

Add the pci related code for csky arch to support basic pci virtual
function, such as qemu virt-pci-9pfs.
Signed-off-by: NMaJun <majun258@linux.alibaba.com>
Signed-off-by: NGuo Ren <guoren@linux.alibaba.com>

CONFIG_CLKSRC_OF is gone since commit bb0eb050
("clocksource/drivers: Rename CLKSRC_OF to TIMER_OF").  The platform
already selects TIMER_OF.

CONFIG_HAVE_DMA_API_DEBUG is gone since commit 6e88628d ("dma-debug:
remove CONFIG_HAVE_DMA_API_DEBUG").

CONFIG_DEFAULT_DEADLINE is gone since commit f382fb0b ("block:
remove legacy IO schedulers").
Signed-off-by: NKrzysztof Kozlowski <krzk@kernel.org>
Signed-off-by: NGuo Ren <guoren@linux.alibaba.com>

Fix wording in help text for the CPU_HAS_LDSTEX symbol.
Signed-off-by: NRandy Dunlap <rdunlap@infradead.org>
Signed-off-by: NGuo Ren <guoren@kernel.org>
Signed-off-by: NGuo Ren <guoren@linux.alibaba.com>

Some CPUs don't support icache specific instructions to flush icache
lines in broadcast way. We use cpu control registers to flush local
icache and use IPI to notify other cores.
Signed-off-by: NGuo Ren <guoren@linux.alibaba.com>

Such as snps,dw-apb-ictl
Signed-off-by: NGuo Ren <guoren@linux.alibaba.com>

After fixaddr_init is separated from highmem, we could use tcm
without highmem selected. (610 (abiv1) don't support highmem,
but it could use tcm now.)
Signed-off-by: NGuo Ren <guoren@linux.alibaba.com>

The implementation are not only used by TCM but also used by sram on
SOC bus. It follow existed linux tcm software interface, so that old
tcm application codes could be re-used directly.

Software interface list in asm/tcm.h:
 - Variables/Const: 	__tcmdata, __tcmconst
 - Functions:		__tcmfunc, __tcmlocalfunc
 - Malloc/Free:		tcm_alloc, tcm_free

In linux menuconfig:
 - Choose a TCM contain instrctions + data or separated in ITCM/DTCM.
 - Determine TCM_BASE (DTCM_BASE) in phyiscal address.
 - Determine size of TCM or ITCM(DTCM) in page counts.

Here is hello tcm example from Documentation/arm/tcm.rst which could
be directly used:

/* Uninitialized data */
static u32 __tcmdata tcmvar;
/* Initialized data */
static u32 __tcmdata tcmassigned = 0x2BADBABEU;
/* Constant */
static const u32 __tcmconst tcmconst = 0xCAFEBABEU;

static void __tcmlocalfunc tcm_to_tcm(void)
{
	int i;
	for (i = 0; i < 100; i++)
		tcmvar ++;
}

static void __tcmfunc hello_tcm(void)
{
	/* Some abstract code that runs in ITCM */
	int i;
	for (i = 0; i < 100; i++) {
		tcmvar ++;
	}
	tcm_to_tcm();
}

static void __init test_tcm(void)
{
	u32 *tcmem;
	int i;

	hello_tcm();
	printk("Hello TCM executed from ITCM RAM\n");

	printk("TCM variable from testrun: %u @ %p\n", tcmvar, &tcmvar);
	tcmvar = 0xDEADBEEFU;
	printk("TCM variable: 0x%x @ %p\n", tcmvar, &tcmvar);

	printk("TCM assigned variable: 0x%x @ %p\n", tcmassigned, &tcmassigned);

	printk("TCM constant: 0x%x @ %p\n", tcmconst, &tcmconst);

	/* Allocate some TCM memory from the pool */
	tcmem = tcm_alloc(20);
	if (tcmem) {
		printk("TCM Allocated 20 bytes of TCM @ %p\n", tcmem);
		tcmem[0] = 0xDEADBEEFU;
		tcmem[1] = 0x2BADBABEU;
		tcmem[2] = 0xCAFEBABEU;
		tcmem[3] = 0xDEADBEEFU;
		tcmem[4] = 0x2BADBABEU;
		for (i = 0; i < 5; i++)
			printk("TCM tcmem[%d] = %08x\n", i, tcmem[i]);
		tcm_free(tcmem, 20);
	}
}

TODO:
 - Separate fixup mapping from highmem
 - Support abiv1
Signed-off-by: NGuo Ren <guoren@linux.alibaba.com>

This is a basic -fstack-protector support without per-task canary
switching. The protector will report something like when stack
corruption is detected:

It's tested with strcpy local array overflow in sys_kill and get:
stack-protector: Kernel stack is corrupted in: sys_kill+0x23c/0x23c

TODO:
 - Support task switch for different cannary
Signed-off-by: NMao Han <han_mao@c-sky.com>
Signed-off-by: NGuo Ren <guoren@linux.alibaba.com>

Use the generic ioremap_prot and iounmap helpers.
Signed-off-by: NChristoph Hellwig <hch@lst.de>
Acked-by: NGuo Ren <guoren@kernel.org>

Let arch help to select interrupt controller's and timer's drivers
instead of people using menuconfig to select. This help the mini system
boot up.
Signed-off-by: NGuo Ren <ren_guo@c-sky.com>
Cc: Arnd Bergmann <arnd@arndb.de>

Add SPDX license identifiers to all Make/Kconfig files which:

 - Have no license information of any form

These files fall under the project license, GPL v2 only. The resulting SPDX
license identifier is:

  GPL-2.0-only
Signed-off-by: NThomas Gleixner <tglx@linutronix.de>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

Add a Kconfig symbol that indicates an architecture provides a
arch_dma_prep_coherent implementation, and provide a stub otherwise.

This will allow the generic dma-iommu code to use it while still
allowing to be built for cache coherent architectures.
Signed-off-by: NChristoph Hellwig <hch@lst.de>
Reviewed-by: NRobin Murphy <robin.murphy@arm.com>

This patch implements the perf registers sampling and validation API
for csky arch. The valid registers and their register ID are defined in
perf_regs.h. Perf tool can backtrace in userspace with unwind library
and the registers/user stack dump support.
Signed-off-by: NMao Han <han_mao@c-sky.com>
Signed-off-by: NGuo Ren <ren_guo@c-sky.com>

Previous syscall_trace implementation couldn't support AUDITSYSCALL and
SYSCALL_TRACEPOINTS. Now we redesign it to support audit_syscall
and syscall_tracepoints just like other archs'.
Signed-off-by: NGuo Ren <ren_guo@c-sky.com>
Cc: Dmitry V. Levin <ldv@altlinux.org>
Cc: Arnd Bergmann <arnd@arndb.de>

Support dynamic ftrace including dynamic graph tracer. Gcc-csky with -pg
will produce call site in every function prologue and we can use these
call site to hook trace function.

gcc with -pg origin call site:
	push	lr
	jbsr	_mcount
	nop32
	nop32

If the (callee - caller)'s offset is in range of bsr instruction, we'll
modify code with:
	push	lr
	bsr	_mcount
	nop32
	nop32
Else if the (callee - caller)'s offset is out of bsr instrunction, we'll
modify code with:
	push	lr
	movih	r26, ...
	ori	r26, ...
	jsr	r26

(r26 is reserved for jsr link reg in csky abiv2 spec.)
Signed-off-by: NGuo Ren <ren_guo@c-sky.com>

Currently, we have two different implementation of rwsem:

 1) CONFIG_RWSEM_GENERIC_SPINLOCK (rwsem-spinlock.c)
 2) CONFIG_RWSEM_XCHGADD_ALGORITHM (rwsem-xadd.c)

As we are going to use a single generic implementation for rwsem-xadd.c
and no architecture-specific code will be needed, there is no point
in keeping two different implementations of rwsem. In most cases, the
performance of rwsem-spinlock.c will be worse. It also doesn't get all
the performance tuning and optimizations that had been implemented in
rwsem-xadd.c over the years.

For simplication, we are going to remove rwsem-spinlock.c and make all
architectures use a single implementation of rwsem - rwsem-xadd.c.

All references to RWSEM_GENERIC_SPINLOCK and RWSEM_XCHGADD_ALGORITHM
in the code are removed.
Suggested-by: NPeter Zijlstra <peterz@infradead.org>
Signed-off-by: NWaiman Long <longman@redhat.com>
Signed-off-by: NPeter Zijlstra (Intel) <peterz@infradead.org>
Acked-by: NLinus Torvalds <torvalds@linux-foundation.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Davidlohr Bueso <dave@stgolabs.net>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Tim Chen <tim.c.chen@linux.intel.com>
Cc: Will Deacon <will.deacon@arm.com>
Cc: linux-arm-kernel@lists.infradead.org
Cc: linux-c6x-dev@linux-c6x.org
Cc: linux-m68k@lists.linux-m68k.org
Cc: linux-riscv@lists.infradead.org
Cc: linux-um@lists.infradead.org
Cc: linux-xtensa@linux-xtensa.org
Cc: linuxppc-dev@lists.ozlabs.org
Cc: nios2-dev@lists.rocketboards.org
Cc: openrisc@lists.librecores.org
Cc: uclinux-h8-devel@lists.sourceforge.jp
Link: https://lkml.kernel.org/r/20190322143008.21313-3-longman@redhat.comSigned-off-by: NIngo Molnar <mingo@kernel.org>

This API is primarily used through DT entries, but two architectures
and two drivers call it directly.  So instead of selecting the config
symbol for random architectures pull it in implicitly for the actual
users.  Also rename the Kconfig option to describe the feature better.
Signed-off-by: NChristoph Hellwig <hch@lst.de>
Acked-by: Paul Burton <paul.burton@mips.com> # MIPS
Acked-by: NLee Jones <lee.jones@linaro.org>
Reviewed-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

All new 32-bit architectures should have 64-bit userspace off_t type, but
existing architectures has 32-bit ones.

To enforce the rule, new config option is added to arch/Kconfig that defaults
ARCH_32BIT_OFF_T to be disabled for new 32-bit architectures. All existing
32-bit architectures enable it explicitly.

New option affects force_o_largefile() behaviour. Namely, if userspace
off_t is 64-bits long, we have no reason to reject user to open big files.

Note that even if architectures has only 64-bit off_t in the kernel
(arc, c6x, h8300, hexagon, nios2, openrisc, and unicore32),
a libc may use 32-bit off_t, and therefore want to limit the file size
to 4GB unless specified differently in the open flags.
Signed-off-by: NYury Norov <ynorov@caviumnetworks.com>
Acked-by: NArnd Bergmann <arnd@arndb.de>
Signed-off-by: NYury Norov <ynorov@marvell.com>
Signed-off-by: NArnd Bergmann <arnd@arndb.de>

The OF_RESERVED_MEM can be used if we have either CMA or the generic
declare coherent code built and we support the early flattened DT.

So don't bother making it a user visible options that is selected
by most configs that fit the above category, but just select it when
the requirements are met.
Signed-off-by: NChristoph Hellwig <hch@lst.de>
Reviewed-by: NRob Herring <robh@kernel.org>

This adds basic perf support for all C-SKY CPUs. Hardware events are
only supported by 807/810/860.
Signed-off-by: NGuo Ren <ren_guo@c-sky.com>

With csky-gcc -pg -mbacktrace, ftrace call graph supported.
Signed-off-by: NGuo Ren <ren_guo@c-sky.com>

When gcc with -pg, it'll add _mcount stub in every function. We need
implement the _mcount in kernel and ftrace depends on stackstrace.

To do: call-graph, dynamic ftrace
Signed-off-by: NGuo Ren <ren_guo@c-sky.com>

The gcc option "-mbacktrace" will push fp(r8),lr into stack and we could
unwind the stack with:
	fp = *fp
	lr = (unsigned int *)fp[1]
Signed-off-by: NGuo Ren <ren_guo@c-sky.com>

This is a simple implement of CPU-hotplug for power saving. CPU use
wait instruction to enter power saving mode and waiting for IPI wakeup
signal.
Signed-off-by: NGuo Ren <ren_guo@c-sky.com>

All architectures except for sparc64 use the dma-direct code in some
form, and even for sparc64 we had the discussion of a direct mapping
mode a while ago.  In preparation for directly calling the direct
mapping code don't bother having it optionally but always build the
code in.  This is a minor hardship for some powerpc and arm configs
that don't pull it in yet (although they should in a relase ot two),
and sparc64 which currently doesn't need it at all, but it will
reduce the ifdef mess we'd otherwise need significantly.
Signed-off-by: NChristoph Hellwig <hch@lst.de>
Acked-by: NJesper Dangaard Brouer <brouer@redhat.com>
Tested-by: NJesper Dangaard Brouer <brouer@redhat.com>
Tested-by: NTony Luck <tony.luck@intel.com>

The csky code was largely copied from arm/arm64, so switch to the
generic arm64-based implementation instead.
Signed-off-by: NChristoph Hellwig <hch@lst.de>
Acked-by: NGuo Ren <ren_guo@c-sky.com>

This option is gone past Linux 4.19.
Signed-off-by: NChristoph Hellwig <hch@lst.de>
Acked-by: NGuo Ren <ren_guo@c-sky.com>

The dma remap code only makes sense for not cache coherent architectures
(or possibly the corner case of highmem CMA allocations) and currently
is only used by arm, arm64, csky and xtensa.  Split it out into a
separate file with a separate Kconfig symbol, which gets the right
copyright notice given that this code was written by Laura Abbott
working for Code Aurora at that point.
Signed-off-by: NChristoph Hellwig <hch@lst.de>
Acked-by: NLaura Abbott <labbott@redhat.com>
Reviewed-by: NRobin Murphy <robin.murphy@arm.com>

All architecures use memblock for early memory management. There is no need
for the CONFIG_HAVE_MEMBLOCK configuration option.

[rppt@linux.vnet.ibm.com: of/fdt: fixup #ifdefs]
  Link: http://lkml.kernel.org/r/20180919103457.GA20545@rapoport-lnx
[rppt@linux.vnet.ibm.com: csky: fixups after bootmem removal]
  Link: http://lkml.kernel.org/r/20180926112744.GC4628@rapoport-lnx
[rppt@linux.vnet.ibm.com: remove stale #else and the code it protects]
  Link: http://lkml.kernel.org/r/1538067825-24835-1-git-send-email-rppt@linux.vnet.ibm.com
Link: http://lkml.kernel.org/r/1536927045-23536-4-git-send-email-rppt@linux.vnet.ibm.comSigned-off-by: NMike Rapoport <rppt@linux.vnet.ibm.com>
Acked-by: NMichal Hocko <mhocko@suse.com>
Tested-by: NJonathan Cameron <jonathan.cameron@huawei.com>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Chris Zankel <chris@zankel.net>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Geert Uytterhoeven <geert@linux-m68k.org>
Cc: Greentime Hu <green.hu@gmail.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Guan Xuetao <gxt@pku.edu.cn>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: "James E.J. Bottomley" <jejb@parisc-linux.org>
Cc: Jonas Bonn <jonas@southpole.se>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Ley Foon Tan <lftan@altera.com>
Cc: Mark Salter <msalter@redhat.com>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Matt Turner <mattst88@gmail.com>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Michal Simek <monstr@monstr.eu>
Cc: Palmer Dabbelt <palmer@sifive.com>
Cc: Paul Burton <paul.burton@mips.com>
Cc: Richard Kuo <rkuo@codeaurora.org>
Cc: Richard Weinberger <richard@nod.at>
Cc: Rich Felker <dalias@libc.org>
Cc: Russell King <linux@armlinux.org.uk>
Cc: Serge Semin <fancer.lancer@gmail.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Tony Luck <tony.luck@intel.com>
Cc: Vineet Gupta <vgupta@synopsys.com>
Cc: Yoshinori Sato <ysato@users.sourceforge.jp>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

All achitectures select NO_BOOTMEM which essentially becomes 'Y' for any
kernel configuration and therefore it can be removed.

[alexander.h.duyck@linux.intel.com: remove now defunct NO_BOOTMEM from depends list for deferred init]
  Link: http://lkml.kernel.org/r/20180925201814.3576.15105.stgit@localhost.localdomain
Link: http://lkml.kernel.org/r/1536927045-23536-3-git-send-email-rppt@linux.vnet.ibm.comSigned-off-by: NMike Rapoport <rppt@linux.vnet.ibm.com>
Signed-off-by: NAlexander Duyck <alexander.h.duyck@linux.intel.com>
Acked-by: NMichal Hocko <mhocko@suse.com>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Chris Zankel <chris@zankel.net>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Geert Uytterhoeven <geert@linux-m68k.org>
Cc: Greentime Hu <green.hu@gmail.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Guan Xuetao <gxt@pku.edu.cn>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: "James E.J. Bottomley" <jejb@parisc-linux.org>
Cc: Jonas Bonn <jonas@southpole.se>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Ley Foon Tan <lftan@altera.com>
Cc: Mark Salter <msalter@redhat.com>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Matt Turner <mattst88@gmail.com>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Michal Simek <monstr@monstr.eu>
Cc: Palmer Dabbelt <palmer@sifive.com>
Cc: Paul Burton <paul.burton@mips.com>
Cc: Richard Kuo <rkuo@codeaurora.org>
Cc: Richard Weinberger <richard@nod.at>
Cc: Rich Felker <dalias@libc.org>
Cc: Russell King <linux@armlinux.org.uk>
Cc: Serge Semin <fancer.lancer@gmail.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Tony Luck <tony.luck@intel.com>
Cc: Vineet Gupta <vgupta@synopsys.com>
Cc: Yoshinori Sato <ysato@users.sourceforge.jp>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

This patch adds Makefile, Kconfig for build infrastructure.
Signed-off-by: NGuo Ren <ren_guo@c-sky.com>
Acked-by: NArnd Bergmann <arnd@arndb.de>