--- /dev/null
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ * AMD Platform Management Framework Driver
+ *
+ * Copyright (c) 2022, Advanced Micro Devices, Inc.
+ * All Rights Reserved.
+ *
+ * Author: Shyam Sundar S K <Shyam-sundar.S-k@amd.com>
+ */
+
+#include <linux/iopoll.h>
+#include <linux/module.h>
+#include <linux/pci.h>
+#include <linux/platform_device.h>
+#include "pmf.h"
+
+/* PMF-SMU communication registers */
+#define AMD_PMF_REGISTER_MESSAGE 0xA18
+#define AMD_PMF_REGISTER_RESPONSE 0xA78
+#define AMD_PMF_REGISTER_ARGUMENT 0xA58
+
+/* Base address of SMU for mapping physical address to virtual address */
+#define AMD_PMF_SMU_INDEX_ADDRESS 0xB8
+#define AMD_PMF_SMU_INDEX_DATA 0xBC
+#define AMD_PMF_MAPPING_SIZE 0x01000
+#define AMD_PMF_BASE_ADDR_OFFSET 0x10000
+#define AMD_PMF_BASE_ADDR_LO 0x13B102E8
+#define AMD_PMF_BASE_ADDR_HI 0x13B102EC
+#define AMD_PMF_BASE_ADDR_LO_MASK GENMASK(15, 0)
+#define AMD_PMF_BASE_ADDR_HI_MASK GENMASK(31, 20)
+
+/* SMU Response Codes */
+#define AMD_PMF_RESULT_OK 0x01
+#define AMD_PMF_RESULT_CMD_REJECT_BUSY 0xFC
+#define AMD_PMF_RESULT_CMD_REJECT_PREREQ 0xFD
+#define AMD_PMF_RESULT_CMD_UNKNOWN 0xFE
+#define AMD_PMF_RESULT_FAILED 0xFF
+
+/* List of supported CPU ids */
+#define AMD_CPU_ID_PS 0x14e8
+
+#define PMF_MSG_DELAY_MIN_US 50
+#define RESPONSE_REGISTER_LOOP_MAX 20000
+
+#define DELAY_MIN_US 2000
+#define DELAY_MAX_US 3000
+
+static inline u32 amd_pmf_reg_read(struct amd_pmf_dev *dev, int reg_offset)
+{
+ return ioread32(dev->regbase + reg_offset);
+}
+
+static inline void amd_pmf_reg_write(struct amd_pmf_dev *dev, int reg_offset, u32 val)
+{
+ iowrite32(val, dev->regbase + reg_offset);
+}
+
+static void __maybe_unused amd_pmf_dump_registers(struct amd_pmf_dev *dev)
+{
+ u32 value;
+
+ value = amd_pmf_reg_read(dev, AMD_PMF_REGISTER_RESPONSE);
+ dev_dbg(dev->dev, "AMD_PMF_REGISTER_RESPONSE:%x\n", value);
+
+ value = amd_pmf_reg_read(dev, AMD_PMF_REGISTER_ARGUMENT);
+ dev_dbg(dev->dev, "AMD_PMF_REGISTER_ARGUMENT:%d\n", value);
+
+ value = amd_pmf_reg_read(dev, AMD_PMF_REGISTER_MESSAGE);
+ dev_dbg(dev->dev, "AMD_PMF_REGISTER_MESSAGE:%x\n", value);
+}
+
+int amd_pmf_send_cmd(struct amd_pmf_dev *dev, u8 message, bool get, u32 arg, u32 *data)
+{
+ int rc;
+ u32 val;
+
+ mutex_lock(&dev->lock);
+
+ /* Wait until we get a valid response */
+ rc = readx_poll_timeout(ioread32, dev->regbase + AMD_PMF_REGISTER_RESPONSE,
+ val, val != 0, PMF_MSG_DELAY_MIN_US,
+ PMF_MSG_DELAY_MIN_US * RESPONSE_REGISTER_LOOP_MAX);
+ if (rc) {
+ dev_err(dev->dev, "failed to talk to SMU\n");
+ goto out_unlock;
+ }
+
+ /* Write zero to response register */
+ amd_pmf_reg_write(dev, AMD_PMF_REGISTER_RESPONSE, 0);
+
+ /* Write argument into argument register */
+ amd_pmf_reg_write(dev, AMD_PMF_REGISTER_ARGUMENT, arg);
+
+ /* Write message ID to message ID register */
+ amd_pmf_reg_write(dev, AMD_PMF_REGISTER_MESSAGE, message);
+
+ /* Wait until we get a valid response */
+ rc = readx_poll_timeout(ioread32, dev->regbase + AMD_PMF_REGISTER_RESPONSE,
+ val, val != 0, PMF_MSG_DELAY_MIN_US,
+ PMF_MSG_DELAY_MIN_US * RESPONSE_REGISTER_LOOP_MAX);
+ if (rc) {
+ dev_err(dev->dev, "SMU response timed out\n");
+ goto out_unlock;
+ }
+
+ switch (val) {
+ case AMD_PMF_RESULT_OK:
+ if (get) {
+ /* PMFW may take longer time to return back the data */
+ usleep_range(DELAY_MIN_US, 10 * DELAY_MAX_US);
+ *data = amd_pmf_reg_read(dev, AMD_PMF_REGISTER_ARGUMENT);
+ }
+ break;
+ case AMD_PMF_RESULT_CMD_REJECT_BUSY:
+ dev_err(dev->dev, "SMU not ready. err: 0x%x\n", val);
+ rc = -EBUSY;
+ goto out_unlock;
+ case AMD_PMF_RESULT_CMD_UNKNOWN:
+ dev_err(dev->dev, "SMU cmd unknown. err: 0x%x\n", val);
+ rc = -EINVAL;
+ goto out_unlock;
+ case AMD_PMF_RESULT_CMD_REJECT_PREREQ:
+ case AMD_PMF_RESULT_FAILED:
+ default:
+ dev_err(dev->dev, "SMU cmd failed. err: 0x%x\n", val);
+ rc = -EIO;
+ goto out_unlock;
+ }
+
+out_unlock:
+ mutex_unlock(&dev->lock);
+ amd_pmf_dump_registers(dev);
+ return rc;
+}
+
+static const struct pci_device_id pmf_pci_ids[] = {
+ { PCI_DEVICE(PCI_VENDOR_ID_AMD, AMD_CPU_ID_PS) },
+ { }
+};
+
+static const struct acpi_device_id amd_pmf_acpi_ids[] = {
+ {"AMDI0102", 0},
+ { }
+};
+MODULE_DEVICE_TABLE(acpi, amd_pmf_acpi_ids);
+
+static int amd_pmf_probe(struct platform_device *pdev)
+{
+ struct amd_pmf_dev *dev;
+ struct pci_dev *rdev;
+ u32 base_addr_lo;
+ u32 base_addr_hi;
+ u64 base_addr;
+ u32 val;
+ int err;
+
+ dev = devm_kzalloc(&pdev->dev, sizeof(*dev), GFP_KERNEL);
+ if (!dev)
+ return -ENOMEM;
+
+ dev->dev = &pdev->dev;
+
+ rdev = pci_get_domain_bus_and_slot(0, 0, PCI_DEVFN(0, 0));
+ if (!rdev || !pci_match_id(pmf_pci_ids, rdev)) {
+ pci_dev_put(rdev);
+ return -ENODEV;
+ }
+
+ dev->cpu_id = rdev->device;
+ err = pci_write_config_dword(rdev, AMD_PMF_SMU_INDEX_ADDRESS, AMD_PMF_BASE_ADDR_LO);
+ if (err) {
+ dev_err(dev->dev, "error writing to 0x%x\n", AMD_PMF_SMU_INDEX_ADDRESS);
+ pci_dev_put(rdev);
+ return pcibios_err_to_errno(err);
+ }
+
+ err = pci_read_config_dword(rdev, AMD_PMF_SMU_INDEX_DATA, &val);
+ if (err) {
+ pci_dev_put(rdev);
+ return pcibios_err_to_errno(err);
+ }
+
+ base_addr_lo = val & AMD_PMF_BASE_ADDR_HI_MASK;
+
+ err = pci_write_config_dword(rdev, AMD_PMF_SMU_INDEX_ADDRESS, AMD_PMF_BASE_ADDR_HI);
+ if (err) {
+ dev_err(dev->dev, "error writing to 0x%x\n", AMD_PMF_SMU_INDEX_ADDRESS);
+ pci_dev_put(rdev);
+ return pcibios_err_to_errno(err);
+ }
+
+ err = pci_read_config_dword(rdev, AMD_PMF_SMU_INDEX_DATA, &val);
+ if (err) {
+ pci_dev_put(rdev);
+ return pcibios_err_to_errno(err);
+ }
+
+ base_addr_hi = val & AMD_PMF_BASE_ADDR_LO_MASK;
+ pci_dev_put(rdev);
+ base_addr = ((u64)base_addr_hi << 32 | base_addr_lo);
+
+ dev->regbase = devm_ioremap(dev->dev, base_addr + AMD_PMF_BASE_ADDR_OFFSET,
+ AMD_PMF_MAPPING_SIZE);
+ if (!dev->regbase)
+ return -ENOMEM;
+
+ platform_set_drvdata(pdev, dev);
+
+ mutex_init(&dev->lock);
+ dev_info(dev->dev, "registered PMF device successfully\n");
+
+ return 0;
+}
+
+static int amd_pmf_remove(struct platform_device *pdev)
+{
+ struct amd_pmf_dev *dev = platform_get_drvdata(pdev);
+
+ mutex_destroy(&dev->lock);
+ kfree(dev->buf);
+ return 0;
+}
+
+static struct platform_driver amd_pmf_driver = {
+ .driver = {
+ .name = "amd-pmf",
+ .acpi_match_table = amd_pmf_acpi_ids,
+ },
+ .probe = amd_pmf_probe,
+ .remove = amd_pmf_remove,
+};
+module_platform_driver(amd_pmf_driver);
+
+MODULE_LICENSE("GPL");
+MODULE_DESCRIPTION("AMD Platform Management Framework Driver");
projects / platform / kernel / linux-rpi.git / commitdiff