| // SPDX-License-Identifier: ISC |
| /* Initialize Owl Emulation Devices |
| * |
| * Copyright (C) 2016 Christian Lamparter <chunkeey@gmail.com> |
| * Copyright (C) 2016 Martin Blumenstingl <martin.blumenstingl@googlemail.com> |
| * |
| * Some devices (like the Cisco Meraki Z1 Cloud Managed Teleworker Gateway) |
| * need to be able to initialize the PCIe wifi device. Normally, this is done |
| * during the early stages as a pci quirk. |
| * However, this isn't possible for devices which have the init code for the |
| * Atheros chip stored on UBI Volume on NAND. Hence, this module can be used to |
| * initialize the chip when the user-space is ready to extract the init code. |
| */ |
| #include <linux/module.h> |
| #include <linux/completion.h> |
| #include <linux/etherdevice.h> |
| #include <linux/firmware.h> |
| #include <linux/pci.h> |
| #include <linux/delay.h> |
| #include <linux/platform_device.h> |
| #include <linux/ath9k_platform.h> |
| #include <linux/nvmem-consumer.h> |
| #include <linux/workqueue.h> |
| |
| struct owl_ctx { |
| struct pci_dev *pdev; |
| struct completion eeprom_load; |
| struct work_struct work; |
| struct nvmem_cell *cell; |
| }; |
| |
| #define EEPROM_FILENAME_LEN 100 |
| |
| #define AR5416_EEPROM_MAGIC 0xa55a |
| |
| static int ath9k_pci_fixup(struct pci_dev *pdev, const u16 *cal_data, |
| size_t cal_len) |
| { |
| void __iomem *mem; |
| const void *cal_end = (void *)cal_data + cal_len; |
| const struct { |
| u16 reg; |
| u16 low_val; |
| u16 high_val; |
| } __packed * data; |
| u16 cmd; |
| u32 bar0; |
| bool swap_needed = false; |
| |
| /* also note that we are doing *u16 operations on the file */ |
| if (cal_len > 4096 || cal_len < 0x200 || (cal_len & 1) == 1) { |
| dev_err(&pdev->dev, "eeprom has an invalid size.\n"); |
| return -EINVAL; |
| } |
| |
| if (*cal_data != AR5416_EEPROM_MAGIC) { |
| if (*cal_data != swab16(AR5416_EEPROM_MAGIC)) { |
| dev_err(&pdev->dev, "invalid calibration data\n"); |
| return -EINVAL; |
| } |
| |
| dev_dbg(&pdev->dev, "calibration data needs swapping\n"); |
| swap_needed = true; |
| } |
| |
| dev_info(&pdev->dev, "fixup device configuration\n"); |
| |
| mem = pcim_iomap(pdev, 0, 0); |
| if (!mem) { |
| dev_err(&pdev->dev, "ioremap error\n"); |
| return -EINVAL; |
| } |
| |
| pci_read_config_dword(pdev, PCI_BASE_ADDRESS_0, &bar0); |
| pci_write_config_dword(pdev, PCI_BASE_ADDRESS_0, |
| pci_resource_start(pdev, 0)); |
| pci_read_config_word(pdev, PCI_COMMAND, &cmd); |
| cmd |= PCI_COMMAND_MASTER | PCI_COMMAND_MEMORY; |
| pci_write_config_word(pdev, PCI_COMMAND, cmd); |
| |
| /* set pointer to first reg address */ |
| for (data = (const void *)(cal_data + 3); |
| (const void *)data <= cal_end && data->reg != (u16)~0; |
| data++) { |
| u32 val; |
| u16 reg; |
| |
| reg = data->reg; |
| val = data->low_val; |
| val |= ((u32)data->high_val) << 16; |
| |
| if (swap_needed) { |
| reg = swab16(reg); |
| val = swahb32(val); |
| } |
| |
| iowrite32(val, mem + reg); |
| usleep_range(100, 120); |
| } |
| |
| pci_read_config_word(pdev, PCI_COMMAND, &cmd); |
| cmd &= ~(PCI_COMMAND_MASTER | PCI_COMMAND_MEMORY); |
| pci_write_config_word(pdev, PCI_COMMAND, cmd); |
| |
| pci_write_config_dword(pdev, PCI_BASE_ADDRESS_0, bar0); |
| pcim_iounmap(pdev, mem); |
| |
| pci_disable_device(pdev); |
| |
| return 0; |
| } |
| |
| static void owl_rescan(struct pci_dev *pdev) |
| { |
| struct pci_bus *bus = pdev->bus; |
| |
| pci_lock_rescan_remove(); |
| pci_stop_and_remove_bus_device(pdev); |
| /* the device should come back with the proper |
| * ProductId. But we have to initiate a rescan. |
| */ |
| pci_rescan_bus(bus); |
| pci_unlock_rescan_remove(); |
| } |
| |
| static void owl_fw_cb(const struct firmware *fw, void *context) |
| { |
| struct owl_ctx *ctx = (struct owl_ctx *)context; |
| |
| complete(&ctx->eeprom_load); |
| |
| if (fw) { |
| ath9k_pci_fixup(ctx->pdev, (const u16 *)fw->data, fw->size); |
| owl_rescan(ctx->pdev); |
| } else { |
| dev_err(&ctx->pdev->dev, "no eeprom data received.\n"); |
| } |
| release_firmware(fw); |
| } |
| |
| static const char *owl_get_eeprom_name(struct pci_dev *pdev) |
| { |
| struct device *dev = &pdev->dev; |
| char *eeprom_name; |
| |
| dev_dbg(dev, "using auto-generated eeprom filename\n"); |
| |
| eeprom_name = devm_kzalloc(dev, EEPROM_FILENAME_LEN, GFP_KERNEL); |
| if (!eeprom_name) |
| return NULL; |
| |
| /* this should match the pattern used in ath9k/init.c */ |
| scnprintf(eeprom_name, EEPROM_FILENAME_LEN, "ath9k-eeprom-pci-%s.bin", |
| dev_name(dev)); |
| |
| return eeprom_name; |
| } |
| |
| static void owl_nvmem_work(struct work_struct *work) |
| { |
| struct owl_ctx *ctx = container_of(work, struct owl_ctx, work); |
| void *buf; |
| size_t len; |
| |
| complete(&ctx->eeprom_load); |
| |
| buf = nvmem_cell_read(ctx->cell, &len); |
| if (!IS_ERR(buf)) { |
| ath9k_pci_fixup(ctx->pdev, buf, len); |
| kfree(buf); |
| owl_rescan(ctx->pdev); |
| } else { |
| dev_err(&ctx->pdev->dev, "no nvmem data received.\n"); |
| } |
| } |
| |
| static int owl_nvmem_probe(struct owl_ctx *ctx) |
| { |
| int err; |
| |
| ctx->cell = devm_nvmem_cell_get(&ctx->pdev->dev, "calibration"); |
| if (IS_ERR(ctx->cell)) { |
| err = PTR_ERR(ctx->cell); |
| if (err == -ENOENT || err == -EOPNOTSUPP) |
| return 1; /* not present, try firmware_request */ |
| |
| return err; |
| } |
| |
| INIT_WORK(&ctx->work, owl_nvmem_work); |
| schedule_work(&ctx->work); |
| |
| return 0; |
| } |
| |
| static int owl_probe(struct pci_dev *pdev, |
| const struct pci_device_id *id) |
| { |
| struct owl_ctx *ctx; |
| const char *eeprom_name; |
| int err = 0; |
| |
| if (pcim_enable_device(pdev)) |
| return -EIO; |
| |
| pcim_pin_device(pdev); |
| |
| ctx = devm_kzalloc(&pdev->dev, sizeof(*ctx), GFP_KERNEL); |
| if (!ctx) |
| return -ENOMEM; |
| |
| init_completion(&ctx->eeprom_load); |
| ctx->pdev = pdev; |
| |
| pci_set_drvdata(pdev, ctx); |
| |
| err = owl_nvmem_probe(ctx); |
| if (err <= 0) |
| return err; |
| |
| eeprom_name = owl_get_eeprom_name(pdev); |
| if (!eeprom_name) { |
| dev_err(&pdev->dev, "no eeprom filename found.\n"); |
| return -ENODEV; |
| } |
| |
| err = request_firmware_nowait(THIS_MODULE, true, eeprom_name, |
| &pdev->dev, GFP_KERNEL, ctx, owl_fw_cb); |
| if (err) |
| dev_err(&pdev->dev, "failed to request caldata (%d).\n", err); |
| |
| return err; |
| } |
| |
| static void owl_remove(struct pci_dev *pdev) |
| { |
| struct owl_ctx *ctx = pci_get_drvdata(pdev); |
| |
| if (ctx) { |
| wait_for_completion(&ctx->eeprom_load); |
| pci_set_drvdata(pdev, NULL); |
| } |
| } |
| |
| static const struct pci_device_id owl_pci_table[] = { |
| { PCI_VDEVICE(ATHEROS, 0xff1c) }, /* PCIe */ |
| { PCI_VDEVICE(ATHEROS, 0xff1d) }, /* PCI */ |
| { }, |
| }; |
| MODULE_DEVICE_TABLE(pci, owl_pci_table); |
| |
| static struct pci_driver owl_driver = { |
| .name = KBUILD_MODNAME, |
| .id_table = owl_pci_table, |
| .probe = owl_probe, |
| .remove = owl_remove, |
| }; |
| module_pci_driver(owl_driver); |
| MODULE_AUTHOR("Christian Lamparter <chunkeey@gmail.com>"); |
| MODULE_DESCRIPTION("External EEPROM data loader for Atheros AR500X to AR92XX"); |
| MODULE_LICENSE("Dual BSD/GPL"); |