/* * Stack tracing support * * Copyright (C) 2012 ARM Ltd. * * 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 distributed in the hope that it will be useful, * but WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the * GNU General Public License for more details. * * You should have received a copy of the GNU General Public License * along with this program. If not, see . */ #include #include #include #include #include #include #include /* * AArch64 PCS assigns the frame pointer to x29. * * A simple function prologue looks like this: * sub sp, sp, #0x10 * stp x29, x30, [sp] * mov x29, sp * * A simple function epilogue looks like this: * mov sp, x29 * ldp x29, x30, [sp] * add sp, sp, #0x10 */ int notrace unwind_frame(struct task_struct *tsk, struct stackframe *frame) { unsigned long high, low; unsigned long fp = frame->fp; unsigned long irq_stack_ptr; /* * Switching between stacks is valid when tracing current and in * non-preemptible context. */ if (tsk == current && !preemptible()) irq_stack_ptr = IRQ_STACK_PTR(smp_processor_id()); else irq_stack_ptr = 0; low = frame->sp; /* irq stacks are not THREAD_SIZE aligned */ if (on_irq_stack(frame->sp, raw_smp_processor_id())) high = irq_stack_ptr; else high = ALIGN(low, THREAD_SIZE) - 0x20; if (fp < low || fp > high || fp & 0xf) return -EINVAL; frame->sp = fp + 0x10; frame->fp = READ_ONCE_NOCHECK(*(unsigned long *)(fp)); frame->pc = READ_ONCE_NOCHECK(*(unsigned long *)(fp + 8)); #ifdef CONFIG_FUNCTION_GRAPH_TRACER if (tsk && tsk->ret_stack && (frame->pc == (unsigned long)return_to_handler)) { /* * This is a case where function graph tracer has * modified a return address (LR) in a stack frame * to hook a function return. * So replace it to an original value. */ frame->pc = tsk->ret_stack[frame->graph--].ret; } #endif /* CONFIG_FUNCTION_GRAPH_TRACER */ /* * Check whether we are going to walk through from interrupt stack * to task stack. * If we reach the end of the stack - and its an interrupt stack, * unpack the dummy frame to find the original elr. * * Check the frame->fp we read from the bottom of the irq_stack, * and the original task stack pointer are both in current->stack. */ if (frame->sp == irq_stack_ptr) { struct pt_regs *irq_args; unsigned long orig_sp = IRQ_STACK_TO_TASK_STACK(irq_stack_ptr); if (object_is_on_stack((void *)orig_sp) && object_is_on_stack((void *)frame->fp)) { frame->sp = orig_sp; /* orig_sp is the saved pt_regs, find the elr */ irq_args = (struct pt_regs *)orig_sp; frame->pc = irq_args->pc; } else { /* * This frame has a non-standard format, and we * didn't fix it, because the data looked wrong. * Refuse to output this frame. */ return -EINVAL; } } return 0; } void notrace walk_stackframe(struct task_struct *tsk, struct stackframe *frame, int (*fn)(struct stackframe *, void *), void *data) { while (1) { int ret; if (fn(frame, data)) break; ret = unwind_frame(tsk, frame); if (ret < 0) break; } } EXPORT_SYMBOL(walk_stackframe); #ifdef CONFIG_STACKTRACE struct stack_trace_data { struct stack_trace *trace; unsigned int no_sched_functions; unsigned int skip; }; static int save_trace(struct stackframe *frame, void *d) { struct stack_trace_data *data = d; struct stack_trace *trace = data->trace; unsigned long addr = frame->pc; if (data->no_sched_functions && in_sched_functions(addr)) return 0; if (data->skip) { data->skip--; return 0; } trace->entries[trace->nr_entries++] = addr; return trace->nr_entries >= trace->max_entries; } void save_stack_trace_tsk(struct task_struct *tsk, struct stack_trace *trace) { struct stack_trace_data data; struct stackframe frame; data.trace = trace; data.skip = trace->skip; if (tsk != current) { data.no_sched_functions = 1; frame.fp = thread_saved_fp(tsk); frame.sp = thread_saved_sp(tsk); frame.pc = thread_saved_pc(tsk); } else { data.no_sched_functions = 0; frame.fp = (unsigned long)__builtin_frame_address(0); frame.sp = current_stack_pointer; frame.pc = (unsigned long)save_stack_trace_tsk; } #ifdef CONFIG_FUNCTION_GRAPH_TRACER frame.graph = tsk->curr_ret_stack; #endif walk_stackframe(tsk, &frame, save_trace, &data); if (trace->nr_entries < trace->max_entries) trace->entries[trace->nr_entries++] = ULONG_MAX; } void save_stack_trace(struct stack_trace *trace) { save_stack_trace_tsk(current, trace); } EXPORT_SYMBOL_GPL(save_stack_trace); #endif >2016-11-17 23:24:35 +0530 committerMark Brown <broonie@kernel.org>2016-11-23 16:27:24 +0000 commit383d0fca7035a12f1201277d33e8fc87c9d60c9a (patch) treebb12c78d91ab8d69ae18fbbf4033277481b277ad /drivers/usb/gadget/udc/udc-xilinx.c parent9a40cb0cb8b55ecfdcd3cec1381bcc46ec488588 (diff)
regulator: max77620: add support to configure MPOK
Adding support to configure regulator POK mapping bit to control nRST_IO and GPIO1 POK function. In tegra based platform which uses MAX20024 pmic, when some of regulators are configured FPS_NONE(flexible power sequencer) causes PMIC GPIO1 to go low which lead to various other rails turning off, to avoid this MPOK bit of those regulators need to be set to 0 so that PMIC GPIO1 will not go low. Signed-off-by: Venkat Reddy Talla <vreddytalla@nvidia.com> Acked-by: Lee Jones <lee.jones@linaro.org> Signed-off-by: Mark Brown <broonie@kernel.org>
Diffstat (limited to 'drivers/usb/gadget/udc/udc-xilinx.c')