diff options
Diffstat (limited to 'drivers/platform/x86/intel_speed_select_if/isst_if_mmio.c')
| -rw-r--r-- | drivers/platform/x86/intel_speed_select_if/isst_if_mmio.c | 180 |
1 files changed, 180 insertions, 0 deletions
diff --git a/drivers/platform/x86/intel_speed_select_if/isst_if_mmio.c b/drivers/platform/x86/intel_speed_select_if/isst_if_mmio.c new file mode 100644 index 000000000000..f7266a115a08 --- /dev/null +++ b/drivers/platform/x86/intel_speed_select_if/isst_if_mmio.c @@ -0,0 +1,180 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * Intel Speed Select Interface: MMIO Interface + * Copyright (c) 2019, Intel Corporation. + * All rights reserved. + * + * Author: Srinivas Pandruvada <srinivas.pandruvada@linux.intel.com> + */ + +#include <linux/module.h> +#include <linux/pci.h> +#include <linux/sched/signal.h> +#include <linux/uaccess.h> +#include <uapi/linux/isst_if.h> + +#include "isst_if_common.h" + +struct isst_mmio_range { + int beg; + int end; +}; + +struct isst_mmio_range mmio_range[] = { + {0x04, 0x14}, + {0x20, 0xD0}, +}; + +struct isst_if_device { + void __iomem *punit_mmio; + u32 range_0[5]; + u32 range_1[45]; + struct mutex mutex; +}; + +static long isst_if_mmio_rd_wr(u8 *cmd_ptr, int *write_only, int resume) +{ + struct isst_if_device *punit_dev; + struct isst_if_io_reg *io_reg; + struct pci_dev *pdev; + + io_reg = (struct isst_if_io_reg *)cmd_ptr; + if (io_reg->reg < 0x04 || io_reg->reg > 0xD0) + return -EINVAL; + + if (io_reg->read_write && !capable(CAP_SYS_ADMIN)) + return -EPERM; + + pdev = isst_if_get_pci_dev(io_reg->logical_cpu, 0, 0, 1); + if (!pdev) + return -EINVAL; + + punit_dev = pci_get_drvdata(pdev); + if (!punit_dev) + return -EINVAL; + + /* + * Ensure that operation is complete on a PCI device to avoid read + * write race by using per PCI device mutex. + */ + mutex_lock(&punit_dev->mutex); + if (io_reg->read_write) { + writel(io_reg->value, punit_dev->punit_mmio+io_reg->reg); + *write_only = 1; + } else { + io_reg->value = readl(punit_dev->punit_mmio+io_reg->reg); + *write_only = 0; + } + mutex_unlock(&punit_dev->mutex); + + return 0; +} + +static const struct pci_device_id isst_if_ids[] = { + { PCI_DEVICE(PCI_VENDOR_ID_INTEL, INTEL_RAPL_PRIO_DEVID_0)}, + { 0 }, +}; +MODULE_DEVICE_TABLE(pci, isst_if_ids); + +static int isst_if_probe(struct pci_dev *pdev, const struct pci_device_id *ent) +{ + struct isst_if_device *punit_dev; + struct isst_if_cmd_cb cb; + u32 mmio_base, pcu_base; + u64 base_addr; + int ret; + + punit_dev = devm_kzalloc(&pdev->dev, sizeof(*punit_dev), GFP_KERNEL); + if (!punit_dev) + return -ENOMEM; + + ret = pcim_enable_device(pdev); + if (ret) + return ret; + + ret = pci_read_config_dword(pdev, 0xD0, &mmio_base); + if (ret) + return ret; + + ret = pci_read_config_dword(pdev, 0xFC, &pcu_base); + if (ret) + return ret; + + pcu_base &= GENMASK(10, 0); + base_addr = (u64)mmio_base << 23 | (u64) pcu_base << 12; + punit_dev->punit_mmio = devm_ioremap(&pdev->dev, base_addr, 256); + if (!punit_dev->punit_mmio) + return -ENOMEM; + + mutex_init(&punit_dev->mutex); + pci_set_drvdata(pdev, punit_dev); + + memset(&cb, 0, sizeof(cb)); + cb.cmd_size = sizeof(struct isst_if_io_reg); + cb.offset = offsetof(struct isst_if_io_regs, io_reg); + cb.cmd_callback = isst_if_mmio_rd_wr; + cb.owner = THIS_MODULE; + ret = isst_if_cdev_register(ISST_IF_DEV_MMIO, &cb); + if (ret) + mutex_destroy(&punit_dev->mutex); + + return ret; +} + +static void isst_if_remove(struct pci_dev *pdev) +{ + struct isst_if_device *punit_dev; + + punit_dev = pci_get_drvdata(pdev); + isst_if_cdev_unregister(ISST_IF_DEV_MBOX); + mutex_destroy(&punit_dev->mutex); +} + +static int __maybe_unused isst_if_suspend(struct device *device) +{ + struct pci_dev *pdev = to_pci_dev(device); + struct isst_if_device *punit_dev; + int i; + + punit_dev = pci_get_drvdata(pdev); + for (i = 0; i < ARRAY_SIZE(punit_dev->range_0); ++i) + punit_dev->range_0[i] = readl(punit_dev->punit_mmio + + mmio_range[0].beg + 4 * i); + for (i = 0; i < ARRAY_SIZE(punit_dev->range_1); ++i) + punit_dev->range_1[i] = readl(punit_dev->punit_mmio + + mmio_range[1].beg + 4 * i); + + return 0; +} + +static int __maybe_unused isst_if_resume(struct device *device) +{ + struct pci_dev *pdev = to_pci_dev(device); + struct isst_if_device *punit_dev; + int i; + + punit_dev = pci_get_drvdata(pdev); + for (i = 0; i < ARRAY_SIZE(punit_dev->range_0); ++i) + writel(punit_dev->range_0[i], punit_dev->punit_mmio + + mmio_range[0].beg + 4 * i); + for (i = 0; i < ARRAY_SIZE(punit_dev->range_1); ++i) + writel(punit_dev->range_1[i], punit_dev->punit_mmio + + mmio_range[1].beg + 4 * i); + + return 0; +} + +static SIMPLE_DEV_PM_OPS(isst_if_pm_ops, isst_if_suspend, isst_if_resume); + +static struct pci_driver isst_if_pci_driver = { + .name = "isst_if_pci", + .id_table = isst_if_ids, + .probe = isst_if_probe, + .remove = isst_if_remove, + .driver.pm = &isst_if_pm_ops, +}; + +module_pci_driver(isst_if_pci_driver); + +MODULE_LICENSE("GPL v2"); +MODULE_DESCRIPTION("Intel speed select interface mmio driver"); |