1 files changed, 261 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 000000000..708c8969b
--- /dev/null
+++ b/drivers/net/wireless/ath/ath9k/ath9k_pci_owl_loader.c
@@ -0,0 +1,261 @@
+// 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");