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Release 4.11 arch/arm/mach-bcm/bcm63xx_pmb.c

/*
 * Broadcom BCM63138 PMB initialization for secondary CPU(s)
 *
 * Copyright (C) 2015 Broadcom Corporation
 * Author: Florian Fainelli <f.fainelli@gmail.com>
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation; either version 2 of the License, or
 * (at your option) any later version.
 */
#include <linux/kernel.h>
#include <linux/io.h>
#include <linux/spinlock.h>
#include <linux/reset/bcm63xx_pmb.h>
#include <linux/of.h>
#include <linux/of_address.h>

#include "bcm63xx_smp.h"

/* ARM Control register definitions */

#define CORE_PWR_CTRL_SHIFT	0

#define CORE_PWR_CTRL_MASK	0x3

#define PLL_PWR_ON		BIT(8)

#define PLL_LDO_PWR_ON		BIT(9)

#define PLL_CLAMP_ON		BIT(10)

#define CPU_RESET_N(x)		BIT(13 + (x))

#define NEON_RESET_N		BIT(15)

#define PWR_CTRL_STATUS_SHIFT	28

#define PWR_CTRL_STATUS_MASK	0x3

#define PWR_DOWN_SHIFT		30

#define PWR_DOWN_MASK		0x3

/* CPU Power control register definitions */

#define MEM_PWR_OK		BIT(0)

#define MEM_PWR_ON		BIT(1)

#define MEM_CLAMP_ON		BIT(2)

#define MEM_PWR_OK_STATUS	BIT(4)

#define MEM_PWR_ON_STATUS	BIT(5)

#define MEM_PDA_SHIFT		8

#define MEM_PDA_MASK		0xf

#define  MEM_PDA_CPU_MASK	0x1

#define  MEM_PDA_NEON_MASK	0xf

#define CLAMP_ON		BIT(15)

#define PWR_OK_SHIFT		16

#define PWR_OK_MASK		0xf

#define PWR_ON_SHIFT		20

#define  PWR_CPU_MASK		0x03

#define  PWR_NEON_MASK		0x01

#define PWR_ON_MASK		0xf

#define PWR_OK_STATUS_SHIFT	24

#define PWR_OK_STATUS_MASK	0xf

#define PWR_ON_STATUS_SHIFT	28

#define PWR_ON_STATUS_MASK	0xf


#define ARM_CONTROL		0x30

#define ARM_PWR_CONTROL_BASE	0x34

#define ARM_PWR_CONTROL(x)	(ARM_PWR_CONTROL_BASE + (x) * 0x4)

#define ARM_NEON_L2		0x3c

/* Perform a value write, then spin until the value shifted by
 * shift is seen, masked with mask and is different from cond.
 */

static int bpcm_wr_rd_mask(void __iomem *master, unsigned int addr, u32 off, u32 *val, u32 shift, u32 mask, u32 cond) { int ret; ret = bpcm_wr(master, addr, off, *val); if (ret) return ret; do { ret = bpcm_rd(master, addr, off, val); if (ret) return ret; cpu_relax(); } while (((*val >> shift) & mask) != cond); return ret; }

Contributors

PersonTokensPropCommitsCommitProp
Florian Fainelli100100.00%1100.00%
Total100100.00%1100.00%

/* Global lock to serialize accesses to the PMB registers while we * are bringing up the secondary CPU */ static DEFINE_SPINLOCK(pmb_lock);
static int bcm63xx_pmb_get_resources(struct device_node *dn, void __iomem **base, unsigned int *cpu, unsigned int *addr) { struct of_phandle_args args; int ret; ret = of_property_read_u32(dn, "reg", cpu); if (ret) { pr_err("CPU is missing a reg node\n"); return ret; } ret = of_parse_phandle_with_args(dn, "resets", "#reset-cells", 0, &args); if (ret) { pr_err("CPU is missing a resets phandle\n"); return ret; } if (args.args_count != 2) { pr_err("reset-controller does not conform to reset-cells\n"); return -EINVAL; } *base = of_iomap(args.np, 0); if (!*base) { pr_err("failed remapping PMB register\n"); return -ENOMEM; } /* We do not need the number of zones */ *addr = args.args[0]; return 0; }

Contributors

PersonTokensPropCommitsCommitProp
Florian Fainelli151100.00%1100.00%
Total151100.00%1100.00%


int bcm63xx_pmb_power_on_cpu(struct device_node *dn) { void __iomem *base; unsigned int cpu, addr; unsigned long flags; u32 val, ctrl; int ret; ret = bcm63xx_pmb_get_resources(dn, &base, &cpu, &addr); if (ret) return ret; /* We would not know how to enable a third and greater CPU */ WARN_ON(cpu > 1); spin_lock_irqsave(&pmb_lock, flags); /* Check if the CPU is already on and save the ARM_CONTROL register * value since we will use it later for CPU de-assert once done with * the CPU-specific power sequence */ ret = bpcm_rd(base, addr, ARM_CONTROL, &ctrl); if (ret) goto out; if (ctrl & CPU_RESET_N(cpu)) { pr_info("PMB: CPU%d is already powered on\n", cpu); ret = 0; goto out; } /* Power on PLL */ ret = bpcm_rd(base, addr, ARM_PWR_CONTROL(cpu), &val); if (ret) goto out; val |= (PWR_CPU_MASK << PWR_ON_SHIFT); ret = bpcm_wr_rd_mask(base, addr, ARM_PWR_CONTROL(cpu), &val, PWR_ON_STATUS_SHIFT, PWR_CPU_MASK, PWR_CPU_MASK); if (ret) goto out; val |= (PWR_CPU_MASK << PWR_OK_SHIFT); ret = bpcm_wr_rd_mask(base, addr, ARM_PWR_CONTROL(cpu), &val, PWR_OK_STATUS_SHIFT, PWR_CPU_MASK, PWR_CPU_MASK); if (ret) goto out; val &= ~CLAMP_ON; ret = bpcm_wr(base, addr, ARM_PWR_CONTROL(cpu), val); if (ret) goto out; /* Power on CPU<N> RAM */ val &= ~(MEM_PDA_MASK << MEM_PDA_SHIFT); ret = bpcm_wr(base, addr, ARM_PWR_CONTROL(cpu), val); if (ret) goto out; val |= MEM_PWR_ON; ret = bpcm_wr_rd_mask(base, addr, ARM_PWR_CONTROL(cpu), &val, 0, MEM_PWR_ON_STATUS, MEM_PWR_ON_STATUS); if (ret) goto out; val |= MEM_PWR_OK; ret = bpcm_wr_rd_mask(base, addr, ARM_PWR_CONTROL(cpu), &val, 0, MEM_PWR_OK_STATUS, MEM_PWR_OK_STATUS); if (ret) goto out; val &= ~MEM_CLAMP_ON; ret = bpcm_wr(base, addr, ARM_PWR_CONTROL(cpu), val); if (ret) goto out; /* De-assert CPU reset */ ctrl |= CPU_RESET_N(cpu); ret = bpcm_wr(base, addr, ARM_CONTROL, ctrl); out: spin_unlock_irqrestore(&pmb_lock, flags); iounmap(base); return ret; }

Contributors

PersonTokensPropCommitsCommitProp
Florian Fainelli41399.28%150.00%
Dan Carpenter30.72%150.00%
Total416100.00%2100.00%


Overall Contributors

PersonTokensPropCommitsCommitProp
Florian Fainelli84299.64%150.00%
Dan Carpenter30.36%150.00%
Total845100.00%2100.00%
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