Opens a node in /proc/pcc_test.
Echo 0 for PCC read Echo 1 for PCC write Echo 2 for read base addr of PCC channel
Signed-off-by: Ashwin Chaugule ashwin.chaugule@linaro.org --- drivers/acpi/Makefile | 2 +- drivers/acpi/pcc-test.c | 172 ++++++++++++++++++++++++++++++++++++++++++++++++ 2 files changed, 173 insertions(+), 1 deletion(-) create mode 100644 drivers/acpi/pcc-test.c
diff --git a/drivers/acpi/Makefile b/drivers/acpi/Makefile index d8aa613..f7bbbe9 100644 --- a/drivers/acpi/Makefile +++ b/drivers/acpi/Makefile @@ -74,7 +74,7 @@ obj-$(CONFIG_ACPI_HED) += hed.o obj-$(CONFIG_ACPI_EC_DEBUGFS) += ec_sys.o obj-$(CONFIG_ACPI_CUSTOM_METHOD)+= custom_method.o obj-$(CONFIG_ACPI_BGRT) += bgrt.o -obj-$(CONFIG_ACPI_PCC) += pcc.o +obj-$(CONFIG_ACPI_PCC) += pcc.o pcc-test.o # processor has its own "processor." module_param namespace processor-y := processor_driver.o processor_throttling.o processor-y += processor_idle.o processor_thermal.o diff --git a/drivers/acpi/pcc-test.c b/drivers/acpi/pcc-test.c new file mode 100644 index 0000000..cb6ee10 --- /dev/null +++ b/drivers/acpi/pcc-test.c @@ -0,0 +1,172 @@ +/* + * Copyright (C) 2014 Linaro Ltd. + * Author: Ashwin Chaugule ashwin.chaugule@linaro.org + * + * 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. + * + * 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. + * + */ + +#include <linux/acpi.h> +#include <linux/io.h> +#include <linux/uaccess.h> +#include <linux/init.h> +#include <linux/cpufreq.h> +#include <linux/proc_fs.h> +#include <linux/seq_file.h> +#include <asm/uaccess.h> + +#include <acpi/actbl.h> + +static u64 pcc_comm_base_addr; /* Returned by the Subspace structure */ +static u64 *comm_base_addr; /* For use after ioremap */ + +extern int get_pcc_comm_channel(u32 ss_idx, u64* addr, int *len); +extern u16 send_pcc_cmd(u8 cmd, u8 sci, u32 ss_idx, u64 * __iomem base_addr); + +/* XXX: The PCC Subspace id is hard coded here only for test purposes. + * In reality it should be parsed from the PCC package as described + * in the PCC client table. e.g. CPC for CPPC + */ +#define PCC_SUBSPACE_IDX 0 +#define CMD_COMPLETE 1 + +enum ppc_cmds { + CMD_READ, + CMD_WRITE, + RESERVED, +}; + +static u64 reg1, reg2; + +static void run_pcc_test_read(void) +{ + u16 pcc_status; + u64 reg1_addr = comm_base_addr + 8; + u64 reg2_addr = comm_base_addr + 16; + + /* READ part of the test */ + pr_info("Sending PCC read req from Channel base addr: %llx\n", pcc_comm_base_addr); + pcc_status = send_pcc_cmd(CMD_READ, 0, PCC_SUBSPACE_IDX, &pcc_comm_base_addr); + if (pcc_status & CMD_COMPLETE) { + pr_info("Read updated values from Platform.\n"); + reg1 = iorea32(®1_addr); + reg2 = ioread32(®2_addr); + pr_info("updated value of reg1:%llx\n", reg1); + pr_info("updated value of reg2:%llx\n", reg2); + } else + pr_err("Failed to read PCC parameters\n"); +} + +static void run_pcc_test_write(void) +{ + u16 pcc_status; + u64 reg1_addr = comm_base_addr + 8; + u64 reg2_addr = comm_base_addr + 16; + + /* WRITE part of the test */ + reg1++; + reg2++; + + iowrite32(reg1, ®1_addr); + iowrite32(reg2, ®2_addr); + + pr_info("Sending PCC write req from Channel base addr: %p\n", comm_base_addr); + pcc_status = send_pcc_cmd(CMD_WRITE, 0, PCC_SUBSPACE_IDX, comm_base_addr); + if (pcc_status & CMD_COMPLETE) + pr_info("OSPM successfully sent PCC read cmd to platform\n"); + else + pr_err("Failed to write PCC parameters. \n"); +} + +void get_pcc_comm(void) +{ + int ret, len; + + ret = get_pcc_comm_channel(PCC_SUBSPACE_IDX, &pcc_comm_base_addr, &len); + + if (ret) { + pr_err("No PCC Communication channel found\n"); + goto out_err; + } + + comm_base_addr = ioremap_nocache(pcc_comm_base_addr, len); + + if (!comm_base_addr) + pr_err("Could not map PCC communicate channel\n"); + + pr_info("Acquired PCC comm channel base addr: %llx\n", pcc_comm_base_addr); + +out_err: + return; +} + +static ssize_t pcc_test_write(struct file *file, const char __user *buf, + size_t count, loff_t *offs) +{ + char ctl[2]; + + if (count != 2 || *offs) + return -EINVAL; + + if (copy_from_user(ctl, buf, count)) + return -EFAULT; + + switch (ctl[0]) { + case '0': + /* PCC read */ + run_pcc_test_read(); + break; + case '1': + /* PCC write */ + run_pcc_test_write(); + break; + case '2': + /* Get PCC channel */ + get_pcc_comm(); + break; + default: + pr_err("Unknown val\n"); + break; + } + + return count; +} + +static int pcc_test_open(struct inode *inode, struct file *filp) +{ + return 0; +} + +static int pcc_test_release(struct inode *inode, struct file *filp) +{ + return 0; +} + +static const struct file_operations pcc_test_fops = { + .open = pcc_test_open, +// .read = seq_read, + .write = pcc_test_write, + .release = pcc_test_release, +}; + +static int __init pcc_test(void) +{ + struct proc_dir_entry *pe; + + pe = proc_create("pcc_test", 0644, NULL, &pcc_test_fops); + + if (!pe) + return -ENOMEM; + + return 0; +} + +late_initcall(pcc_test);