104 lines
3.0 KiB
C
104 lines
3.0 KiB
C
|
/*
|
||
|
|
* Rockchip rk3288 resume code
|
||
|
|
*
|
||
|
|
* This code is intended to be linked into the embedded resume binary
|
||
|
|
* for the rk3288 SoC
|
||
|
|
*
|
||
|
|
* Copyright (c) 2014 Google, Inc
|
||
|
|
*
|
||
|
|
* 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.
|
||
|
|
*/
|
||
|
|
|
||
|
|
#include <linux/kernel.h>
|
||
|
|
|
||
|
|
#include "rk3288_resume.h"
|
||
|
|
#include "rk3288_resume_embedded.h"
|
||
|
|
|
||
|
|
#define INIT_CPSR (PSR_I_BIT | PSR_F_BIT | SVC_MODE)
|
||
|
|
|
||
|
|
static __noreturn void rk3288_resume(void);
|
||
|
|
|
||
|
|
/* Parameters of early board initialization in SPL */
|
||
|
|
struct rk3288_resume_params rk3288_resume_params
|
||
|
|
__attribute__((section(".resume_params"))) = {
|
||
|
|
.resume_loc = rk3288_resume,
|
||
|
|
};
|
||
|
|
|
||
|
|
/**
|
||
|
|
* rk3288_resume_c - Main C entry point for rk3288 at resume time
|
||
|
|
*
|
||
|
|
* This function is called by rk3288_resume() and does the brunt of
|
||
|
|
* any resume processing. After it's done it will call the kernel's
|
||
|
|
* cpu_resume() function (which it finds through its params structure).
|
||
|
|
*
|
||
|
|
* At the time this function is called:
|
||
|
|
* - We know we're on CPU0.
|
||
|
|
* - Interrupts are disabled.
|
||
|
|
* - We've got a stack.
|
||
|
|
* - The cache is turned off, so all addresses are physical.
|
||
|
|
* - SDRAM hasn't been restored yet (if it was off).
|
||
|
|
*
|
||
|
|
* WARNING: This code, the stack and the params structure are all sitting in
|
||
|
|
* PMU SRAM. If you try to write to that memory using an 8-bit access (or even
|
||
|
|
* 16-bit) you'll get an imprecise data abort and it will be very hard to debug.
|
||
|
|
* Keep everything in here as 32-bit wide and aligned. YOU'VE BEEN WARNED.
|
||
|
|
*/
|
||
|
|
static void __noreturn rk3288_resume_c(void)
|
||
|
|
{
|
||
|
|
#ifdef CONFIG_ARM_ERRATA_818325
|
||
|
|
u32 val = 0;
|
||
|
|
|
||
|
|
asm("mrc p15, 0, %0, c15, c0, 1" : "=r" (val));
|
||
|
|
val |= BIT(12);
|
||
|
|
asm("mcr p15, 0, %0, c15, c0, 1" : : "r" (val));
|
||
|
|
#endif
|
||
|
|
|
||
|
|
if (rk3288_resume_params.l2ctlr_f)
|
||
|
|
asm("mcr p15, 1, %0, c9, c0, 2" : :
|
||
|
|
"r" (rk3288_resume_params.l2ctlr));
|
||
|
|
|
||
|
|
if (rk3288_resume_params.ddr_resume_f)
|
||
|
|
rk3288_ddr_resume_early(&rk3288_resume_params.ddr_save_data);
|
||
|
|
|
||
|
|
rk3288_resume_params.cpu_resume();
|
||
|
|
}
|
||
|
|
|
||
|
|
/**
|
||
|
|
* rk3288_resume - First entry point for rk3288 at resume time
|
||
|
|
*
|
||
|
|
* A pointer to this function is stored in rk3288_resume_params. The
|
||
|
|
* kernel uses the pointer in that structure to find this function and
|
||
|
|
* to put its (physical) address in a location that it will get jumped
|
||
|
|
* to at resume time.
|
||
|
|
*
|
||
|
|
* There is no stack at the time this function is called, so this
|
||
|
|
* function is in charge of setting it up. We get to a function with
|
||
|
|
* a normal stack pointer ASAP.
|
||
|
|
*/
|
||
|
|
static void __naked __noreturn rk3288_resume(void)
|
||
|
|
{
|
||
|
|
/* Make sure we're on CPU0, no IRQs and get a stack setup */
|
||
|
|
asm volatile (
|
||
|
|
"msr cpsr_cxf, %0\n"
|
||
|
|
|
||
|
|
/* Only cpu0 continues to run, the others halt here */
|
||
|
|
"mrc p15, 0, r1, c0, c0, 5\n"
|
||
|
|
"and r1, r1, #0xf\n"
|
||
|
|
"cmp r1, #0\n"
|
||
|
|
"beq cpu0run\n"
|
||
|
|
"secondary_loop:\n"
|
||
|
|
"wfe\n"
|
||
|
|
"b secondary_loop\n"
|
||
|
|
|
||
|
|
"cpu0run:\n"
|
||
|
|
"mov sp, %1\n"
|
||
|
|
:
|
||
|
|
: "i" (INIT_CPSR), "r" (&__stack_start)
|
||
|
|
: "cc", "r1", "sp");
|
||
|
|
|
||
|
|
/* Now get into a normal function that can use a stack */
|
||
|
|
rk3288_resume_c();
|
||
|
|
}
|