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@xxxxxxxxxx>
---
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@xxxxxxxxxx>
+ *
+ * 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);
--
1.8.3.2
--
To unsubscribe from this list: send the line "unsubscribe linux-acpi" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
