diff options
Diffstat (limited to 'drivers/soc/bcm/brcmstb/biuctrl.c')
-rw-r--r-- | drivers/soc/bcm/brcmstb/biuctrl.c | 117 |
1 files changed, 117 insertions, 0 deletions
diff --git a/drivers/soc/bcm/brcmstb/biuctrl.c b/drivers/soc/bcm/brcmstb/biuctrl.c new file mode 100644 index 0000000..3c39415 --- /dev/null +++ b/drivers/soc/bcm/brcmstb/biuctrl.c @@ -0,0 +1,117 @@ +/* + * Broadcom STB SoCs Bus Unit Interface controls + * + * Copyright (C) 2015, Broadcom Corporation + * + * 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. + */ + +#define pr_fmt(fmt) "brcmstb: " KBUILD_MODNAME ": " fmt + +#include <linux/kernel.h> +#include <linux/io.h> +#include <linux/of_address.h> +#include <linux/syscore_ops.h> +#include <linux/soc/brcmstb/brcmstb.h> + +#define CPU_CREDIT_REG_OFFSET 0x184 +#define CPU_CREDIT_REG_MCPx_WR_PAIRING_EN_MASK 0x70000000 + +static void __iomem *cpubiuctrl_base; +static bool mcp_wr_pairing_en; + +static int __init mcp_write_pairing_set(void) +{ + u32 creds = 0; + + if (!cpubiuctrl_base) + return -1; + + creds = readl_relaxed(cpubiuctrl_base + CPU_CREDIT_REG_OFFSET); + if (mcp_wr_pairing_en) { + pr_info("MCP: Enabling write pairing\n"); + writel_relaxed(creds | CPU_CREDIT_REG_MCPx_WR_PAIRING_EN_MASK, + cpubiuctrl_base + CPU_CREDIT_REG_OFFSET); + } else if (creds & CPU_CREDIT_REG_MCPx_WR_PAIRING_EN_MASK) { + pr_info("MCP: Disabling write pairing\n"); + writel_relaxed(creds & ~CPU_CREDIT_REG_MCPx_WR_PAIRING_EN_MASK, + cpubiuctrl_base + CPU_CREDIT_REG_OFFSET); + } else { + pr_info("MCP: Write pairing already disabled\n"); + } + + return 0; +} + +static int __init setup_hifcpubiuctrl_regs(void) +{ + struct device_node *np; + int ret = 0; + + np = of_find_compatible_node(NULL, NULL, "brcm,brcmstb-cpu-biu-ctrl"); + if (!np) { + pr_err("missing BIU control node\n"); + return -ENODEV; + } + + cpubiuctrl_base = of_iomap(np, 0); + if (!cpubiuctrl_base) { + pr_err("failed to remap BIU control base\n"); + ret = -ENOMEM; + goto out; + } + + mcp_wr_pairing_en = of_property_read_bool(np, "brcm,write-pairing"); +out: + of_node_put(np); + return ret; +} + +#ifdef CONFIG_PM_SLEEP +static u32 cpu_credit_reg_dump; /* for save/restore */ + +static int brcmstb_cpu_credit_reg_suspend(void) +{ + if (cpubiuctrl_base) + cpu_credit_reg_dump = + readl_relaxed(cpubiuctrl_base + CPU_CREDIT_REG_OFFSET); + return 0; +} + +static void brcmstb_cpu_credit_reg_resume(void) +{ + if (cpubiuctrl_base) + writel_relaxed(cpu_credit_reg_dump, + cpubiuctrl_base + CPU_CREDIT_REG_OFFSET); +} + +static struct syscore_ops brcmstb_cpu_credit_syscore_ops = { + .suspend = brcmstb_cpu_credit_reg_suspend, + .resume = brcmstb_cpu_credit_reg_resume, +}; +#endif + + +void __init brcmstb_biuctrl_init(void) +{ + int ret; + + setup_hifcpubiuctrl_regs(); + + ret = mcp_write_pairing_set(); + if (ret) { + pr_err("MCP: Unable to disable write pairing!\n"); + return; + } + +#ifdef CONFIG_PM_SLEEP + register_syscore_ops(&brcmstb_cpu_credit_syscore_ops); +#endif +} |