diff options
Diffstat (limited to 'drivers/net/wireless/ath/ath9k/ath9k_pci_owl_loader.c')
| -rw-r--r-- | drivers/net/wireless/ath/ath9k/ath9k_pci_owl_loader.c | 215 |
1 files changed, 215 insertions, 0 deletions
diff --git a/drivers/net/wireless/ath/ath9k/ath9k_pci_owl_loader.c b/drivers/net/wireless/ath/ath9k/ath9k_pci_owl_loader.c new file mode 100644 index 0000000..60731e0 --- /dev/null +++ b/drivers/net/wireless/ath/ath9k/ath9k_pci_owl_loader.c @@ -0,0 +1,215 @@ +// 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/version.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> + +struct owl_ctx { + struct completion eeprom_load; +}; + +#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; + + 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_fw_cb(const struct firmware *fw, void *context) +{ + struct pci_dev *pdev = (struct pci_dev *)context; + struct owl_ctx *ctx = (struct owl_ctx *)pci_get_drvdata(pdev); + struct pci_bus *bus; + + complete(&ctx->eeprom_load); + + if (!fw) { + dev_err(&pdev->dev, "no eeprom data received.\n"); + goto release; + } + + /* also note that we are doing *u16 operations on the file */ + if (fw->size > 4096 || fw->size < 0x200 || (fw->size & 1) == 1) { + dev_err(&pdev->dev, "eeprom file has an invalid size.\n"); + goto release; + } + + if (ath9k_pci_fixup(pdev, (const u16 *)fw->data, fw->size)) + goto release; + + pci_lock_rescan_remove(); + bus = pdev->bus; + 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(); + +release: + 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 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); + + eeprom_name = owl_get_eeprom_name(pdev); + if (!eeprom_name) { + dev_err(&pdev->dev, "no eeprom filename found.\n"); + return -ENODEV; + } + + ctx = devm_kzalloc(&pdev->dev, sizeof(*ctx), GFP_KERNEL); + if (!ctx) + return -ENOMEM; + + init_completion(&ctx->eeprom_load); + + pci_set_drvdata(pdev, ctx); + err = request_firmware_nowait(THIS_MODULE, true, eeprom_name, + &pdev->dev, GFP_KERNEL, pdev, 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"); |