diff options
Diffstat (limited to 'kernel/arch/arm/mach-tegra/flowctrl.c')
| -rw-r--r-- | kernel/arch/arm/mach-tegra/flowctrl.c | 171 |
1 files changed, 171 insertions, 0 deletions
diff --git a/kernel/arch/arm/mach-tegra/flowctrl.c b/kernel/arch/arm/mach-tegra/flowctrl.c new file mode 100644 index 000000000..475e78399 --- /dev/null +++ b/kernel/arch/arm/mach-tegra/flowctrl.c @@ -0,0 +1,171 @@ +/* + * arch/arm/mach-tegra/flowctrl.c + * + * functions and macros to control the flowcontroller + * + * Copyright (c) 2010-2012, NVIDIA Corporation. All rights reserved. + * + * This program is free software; you can redistribute it and/or modify it + * under the terms and conditions 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 <http://www.gnu.org/licenses/>. + */ + +#include <linux/cpumask.h> +#include <linux/init.h> +#include <linux/io.h> +#include <linux/kernel.h> +#include <linux/of.h> +#include <linux/of_address.h> + +#include <soc/tegra/fuse.h> + +#include "flowctrl.h" + +static u8 flowctrl_offset_halt_cpu[] = { + FLOW_CTRL_HALT_CPU0_EVENTS, + FLOW_CTRL_HALT_CPU1_EVENTS, + FLOW_CTRL_HALT_CPU1_EVENTS + 8, + FLOW_CTRL_HALT_CPU1_EVENTS + 16, +}; + +static u8 flowctrl_offset_cpu_csr[] = { + FLOW_CTRL_CPU0_CSR, + FLOW_CTRL_CPU1_CSR, + FLOW_CTRL_CPU1_CSR + 8, + FLOW_CTRL_CPU1_CSR + 16, +}; + +static void __iomem *tegra_flowctrl_base; + +static void flowctrl_update(u8 offset, u32 value) +{ + writel(value, tegra_flowctrl_base + offset); + + /* ensure the update has reached the flow controller */ + wmb(); + readl_relaxed(tegra_flowctrl_base + offset); +} + +u32 flowctrl_read_cpu_csr(unsigned int cpuid) +{ + u8 offset = flowctrl_offset_cpu_csr[cpuid]; + + return readl(tegra_flowctrl_base + offset); +} + +void flowctrl_write_cpu_csr(unsigned int cpuid, u32 value) +{ + return flowctrl_update(flowctrl_offset_cpu_csr[cpuid], value); +} + +void flowctrl_write_cpu_halt(unsigned int cpuid, u32 value) +{ + return flowctrl_update(flowctrl_offset_halt_cpu[cpuid], value); +} + +void flowctrl_cpu_suspend_enter(unsigned int cpuid) +{ + unsigned int reg; + int i; + + reg = flowctrl_read_cpu_csr(cpuid); + switch (tegra_get_chip_id()) { + case TEGRA20: + /* clear wfe bitmap */ + reg &= ~TEGRA20_FLOW_CTRL_CSR_WFE_BITMAP; + /* clear wfi bitmap */ + reg &= ~TEGRA20_FLOW_CTRL_CSR_WFI_BITMAP; + /* pwr gating on wfe */ + reg |= TEGRA20_FLOW_CTRL_CSR_WFE_CPU0 << cpuid; + break; + case TEGRA30: + case TEGRA114: + case TEGRA124: + /* clear wfe bitmap */ + reg &= ~TEGRA30_FLOW_CTRL_CSR_WFE_BITMAP; + /* clear wfi bitmap */ + reg &= ~TEGRA30_FLOW_CTRL_CSR_WFI_BITMAP; + /* pwr gating on wfi */ + reg |= TEGRA30_FLOW_CTRL_CSR_WFI_CPU0 << cpuid; + break; + } + reg |= FLOW_CTRL_CSR_INTR_FLAG; /* clear intr flag */ + reg |= FLOW_CTRL_CSR_EVENT_FLAG; /* clear event flag */ + reg |= FLOW_CTRL_CSR_ENABLE; /* pwr gating */ + flowctrl_write_cpu_csr(cpuid, reg); + + for (i = 0; i < num_possible_cpus(); i++) { + if (i == cpuid) + continue; + reg = flowctrl_read_cpu_csr(i); + reg |= FLOW_CTRL_CSR_EVENT_FLAG; + reg |= FLOW_CTRL_CSR_INTR_FLAG; + flowctrl_write_cpu_csr(i, reg); + } +} + +void flowctrl_cpu_suspend_exit(unsigned int cpuid) +{ + unsigned int reg; + + /* Disable powergating via flow controller for CPU0 */ + reg = flowctrl_read_cpu_csr(cpuid); + switch (tegra_get_chip_id()) { + case TEGRA20: + /* clear wfe bitmap */ + reg &= ~TEGRA20_FLOW_CTRL_CSR_WFE_BITMAP; + /* clear wfi bitmap */ + reg &= ~TEGRA20_FLOW_CTRL_CSR_WFI_BITMAP; + break; + case TEGRA30: + case TEGRA114: + case TEGRA124: + /* clear wfe bitmap */ + reg &= ~TEGRA30_FLOW_CTRL_CSR_WFE_BITMAP; + /* clear wfi bitmap */ + reg &= ~TEGRA30_FLOW_CTRL_CSR_WFI_BITMAP; + break; + } + reg &= ~FLOW_CTRL_CSR_ENABLE; /* clear enable */ + reg |= FLOW_CTRL_CSR_INTR_FLAG; /* clear intr */ + reg |= FLOW_CTRL_CSR_EVENT_FLAG; /* clear event */ + flowctrl_write_cpu_csr(cpuid, reg); +} + +static const struct of_device_id matches[] __initconst = { + { .compatible = "nvidia,tegra124-flowctrl" }, + { .compatible = "nvidia,tegra114-flowctrl" }, + { .compatible = "nvidia,tegra30-flowctrl" }, + { .compatible = "nvidia,tegra20-flowctrl" }, + { } +}; + +void __init tegra_flowctrl_init(void) +{ + /* hardcoded fallback if device tree node is missing */ + unsigned long base = 0x60007000; + unsigned long size = SZ_4K; + struct device_node *np; + + np = of_find_matching_node(NULL, matches); + if (np) { + struct resource res; + + if (of_address_to_resource(np, 0, &res) == 0) { + size = resource_size(&res); + base = res.start; + } + + of_node_put(np); + } + + tegra_flowctrl_base = ioremap_nocache(base, size); +} |