| /* Copyright (c) 2015-2016, The Linux Foundation. All rights reserved. |
| * |
| * This program is free software; you can redistribute it and/or modify |
| * it under the terms of the GNU General Public License version 2 and |
| * only version 2 as published by the Free Software Foundation. |
| * |
| * This program is distributed in the hope that it will be useful, |
| * but WITHOUT ANY WARRANTY; without even the implied warranty of |
| * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the |
| * GNU General Public License for more details. |
| */ |
| |
| /* Qualcomm Technologies, Inc. EMAC SGMII Controller driver. |
| */ |
| |
| #include <linux/iopoll.h> |
| #include <linux/acpi.h> |
| #include <linux/of_device.h> |
| #include "emac.h" |
| #include "emac-mac.h" |
| #include "emac-sgmii.h" |
| |
| /* EMAC_SGMII register offsets */ |
| #define EMAC_SGMII_PHY_AUTONEG_CFG2 0x0048 |
| #define EMAC_SGMII_PHY_SPEED_CFG1 0x0074 |
| #define EMAC_SGMII_PHY_IRQ_CMD 0x00ac |
| #define EMAC_SGMII_PHY_INTERRUPT_CLEAR 0x00b0 |
| #define EMAC_SGMII_PHY_INTERRUPT_MASK 0x00b4 |
| #define EMAC_SGMII_PHY_INTERRUPT_STATUS 0x00b8 |
| #define EMAC_SGMII_PHY_RX_CHK_STATUS 0x00d4 |
| |
| #define FORCE_AN_TX_CFG BIT(5) |
| #define FORCE_AN_RX_CFG BIT(4) |
| #define AN_ENABLE BIT(0) |
| |
| #define DUPLEX_MODE BIT(4) |
| #define SPDMODE_1000 BIT(1) |
| #define SPDMODE_100 BIT(0) |
| #define SPDMODE_10 0 |
| |
| #define CDR_ALIGN_DET BIT(6) |
| |
| #define IRQ_GLOBAL_CLEAR BIT(0) |
| |
| #define DECODE_CODE_ERR BIT(7) |
| #define DECODE_DISP_ERR BIT(6) |
| |
| #define SGMII_PHY_IRQ_CLR_WAIT_TIME 10 |
| |
| #define SGMII_PHY_INTERRUPT_ERR (DECODE_CODE_ERR | DECODE_DISP_ERR) |
| #define SGMII_ISR_MASK (SGMII_PHY_INTERRUPT_ERR) |
| |
| #define SERDES_START_WAIT_TIMES 100 |
| |
| /* Initialize the SGMII link between the internal and external PHYs. */ |
| static void emac_sgmii_link_init(struct emac_adapter *adpt) |
| { |
| struct emac_sgmii *phy = &adpt->phy; |
| u32 val; |
| |
| /* Always use autonegotiation. It works no matter how the external |
| * PHY is configured. |
| */ |
| val = readl(phy->base + EMAC_SGMII_PHY_AUTONEG_CFG2); |
| val &= ~(FORCE_AN_RX_CFG | FORCE_AN_TX_CFG); |
| val |= AN_ENABLE; |
| writel(val, phy->base + EMAC_SGMII_PHY_AUTONEG_CFG2); |
| } |
| |
| static int emac_sgmii_irq_clear(struct emac_adapter *adpt, u32 irq_bits) |
| { |
| struct emac_sgmii *phy = &adpt->phy; |
| u32 status; |
| |
| writel_relaxed(irq_bits, phy->base + EMAC_SGMII_PHY_INTERRUPT_CLEAR); |
| writel_relaxed(IRQ_GLOBAL_CLEAR, phy->base + EMAC_SGMII_PHY_IRQ_CMD); |
| /* Ensure interrupt clear command is written to HW */ |
| wmb(); |
| |
| /* After set the IRQ_GLOBAL_CLEAR bit, the status clearing must |
| * be confirmed before clearing the bits in other registers. |
| * It takes a few cycles for hw to clear the interrupt status. |
| */ |
| if (readl_poll_timeout_atomic(phy->base + |
| EMAC_SGMII_PHY_INTERRUPT_STATUS, |
| status, !(status & irq_bits), 1, |
| SGMII_PHY_IRQ_CLR_WAIT_TIME)) { |
| netdev_err(adpt->netdev, |
| "error: failed clear SGMII irq: status:0x%x bits:0x%x\n", |
| status, irq_bits); |
| return -EIO; |
| } |
| |
| /* Finalize clearing procedure */ |
| writel_relaxed(0, phy->base + EMAC_SGMII_PHY_IRQ_CMD); |
| writel_relaxed(0, phy->base + EMAC_SGMII_PHY_INTERRUPT_CLEAR); |
| |
| /* Ensure that clearing procedure finalization is written to HW */ |
| wmb(); |
| |
| return 0; |
| } |
| |
| /* The number of decode errors that triggers a reset */ |
| #define DECODE_ERROR_LIMIT 2 |
| |
| static irqreturn_t emac_sgmii_interrupt(int irq, void *data) |
| { |
| struct emac_adapter *adpt = data; |
| struct emac_sgmii *phy = &adpt->phy; |
| u32 status; |
| |
| status = readl(phy->base + EMAC_SGMII_PHY_INTERRUPT_STATUS); |
| status &= SGMII_ISR_MASK; |
| if (!status) |
| return IRQ_HANDLED; |
| |
| /* If we get a decoding error and CDR is not locked, then try |
| * resetting the internal PHY. The internal PHY uses an embedded |
| * clock with Clock and Data Recovery (CDR) to recover the |
| * clock and data. |
| */ |
| if (status & SGMII_PHY_INTERRUPT_ERR) { |
| int count; |
| |
| /* The SGMII is capable of recovering from some decode |
| * errors automatically. However, if we get multiple |
| * decode errors in a row, then assume that something |
| * is wrong and reset the interface. |
| */ |
| count = atomic_inc_return(&phy->decode_error_count); |
| if (count == DECODE_ERROR_LIMIT) { |
| schedule_work(&adpt->work_thread); |
| atomic_set(&phy->decode_error_count, 0); |
| } |
| } else { |
| /* We only care about consecutive decode errors. */ |
| atomic_set(&phy->decode_error_count, 0); |
| } |
| |
| if (emac_sgmii_irq_clear(adpt, status)) { |
| netdev_warn(adpt->netdev, "failed to clear SGMII interrupt\n"); |
| schedule_work(&adpt->work_thread); |
| } |
| |
| return IRQ_HANDLED; |
| } |
| |
| static void emac_sgmii_reset_prepare(struct emac_adapter *adpt) |
| { |
| struct emac_sgmii *phy = &adpt->phy; |
| u32 val; |
| |
| /* Reset PHY */ |
| val = readl(phy->base + EMAC_EMAC_WRAPPER_CSR2); |
| writel(((val & ~PHY_RESET) | PHY_RESET), phy->base + |
| EMAC_EMAC_WRAPPER_CSR2); |
| /* Ensure phy-reset command is written to HW before the release cmd */ |
| msleep(50); |
| val = readl(phy->base + EMAC_EMAC_WRAPPER_CSR2); |
| writel((val & ~PHY_RESET), phy->base + EMAC_EMAC_WRAPPER_CSR2); |
| /* Ensure phy-reset release command is written to HW before initializing |
| * SGMII |
| */ |
| msleep(50); |
| } |
| |
| void emac_sgmii_reset(struct emac_adapter *adpt) |
| { |
| int ret; |
| |
| emac_sgmii_reset_prepare(adpt); |
| emac_sgmii_link_init(adpt); |
| |
| ret = adpt->phy.initialize(adpt); |
| if (ret) |
| netdev_err(adpt->netdev, |
| "could not reinitialize internal PHY (error=%i)\n", |
| ret); |
| } |
| |
| static int emac_sgmii_open(struct emac_adapter *adpt) |
| { |
| struct emac_sgmii *sgmii = &adpt->phy; |
| int ret; |
| |
| if (sgmii->irq) { |
| /* Make sure interrupts are cleared and disabled first */ |
| ret = emac_sgmii_irq_clear(adpt, 0xff); |
| if (ret) |
| return ret; |
| writel(0, sgmii->base + EMAC_SGMII_PHY_INTERRUPT_MASK); |
| |
| ret = request_irq(sgmii->irq, emac_sgmii_interrupt, 0, |
| "emac-sgmii", adpt); |
| if (ret) { |
| netdev_err(adpt->netdev, |
| "could not register handler for internal PHY\n"); |
| return ret; |
| } |
| } |
| |
| return 0; |
| } |
| |
| static int emac_sgmii_close(struct emac_adapter *adpt) |
| { |
| struct emac_sgmii *sgmii = &adpt->phy; |
| |
| /* Make sure interrupts are disabled */ |
| writel(0, sgmii->base + EMAC_SGMII_PHY_INTERRUPT_MASK); |
| free_irq(sgmii->irq, adpt); |
| |
| return 0; |
| } |
| |
| /* The error interrupts are only valid after the link is up */ |
| static int emac_sgmii_link_up(struct emac_adapter *adpt) |
| { |
| struct emac_sgmii *sgmii = &adpt->phy; |
| int ret; |
| |
| /* Clear and enable interrupts */ |
| ret = emac_sgmii_irq_clear(adpt, 0xff); |
| if (ret) |
| return ret; |
| |
| writel(SGMII_ISR_MASK, sgmii->base + EMAC_SGMII_PHY_INTERRUPT_MASK); |
| |
| return 0; |
| } |
| |
| static int emac_sgmii_link_down(struct emac_adapter *adpt) |
| { |
| struct emac_sgmii *sgmii = &adpt->phy; |
| |
| /* Disable interrupts */ |
| writel(0, sgmii->base + EMAC_SGMII_PHY_INTERRUPT_MASK); |
| synchronize_irq(sgmii->irq); |
| |
| return 0; |
| } |
| |
| static int emac_sgmii_acpi_match(struct device *dev, void *data) |
| { |
| #ifdef CONFIG_ACPI |
| static const struct acpi_device_id match_table[] = { |
| { |
| .id = "QCOM8071", |
| }, |
| {} |
| }; |
| const struct acpi_device_id *id = acpi_match_device(match_table, dev); |
| emac_sgmii_function *initialize = data; |
| |
| if (id) { |
| acpi_handle handle = ACPI_HANDLE(dev); |
| unsigned long long hrv; |
| acpi_status status; |
| |
| status = acpi_evaluate_integer(handle, "_HRV", NULL, &hrv); |
| if (status) { |
| if (status == AE_NOT_FOUND) |
| /* Older versions of the QDF2432 ACPI tables do |
| * not have an _HRV property. |
| */ |
| hrv = 1; |
| else |
| /* Something is wrong with the tables */ |
| return 0; |
| } |
| |
| switch (hrv) { |
| case 1: |
| *initialize = emac_sgmii_init_qdf2432; |
| return 1; |
| case 2: |
| *initialize = emac_sgmii_init_qdf2400; |
| return 1; |
| } |
| } |
| #endif |
| |
| return 0; |
| } |
| |
| static const struct of_device_id emac_sgmii_dt_match[] = { |
| { |
| .compatible = "qcom,fsm9900-emac-sgmii", |
| .data = emac_sgmii_init_fsm9900, |
| }, |
| { |
| .compatible = "qcom,qdf2432-emac-sgmii", |
| .data = emac_sgmii_init_qdf2432, |
| }, |
| {} |
| }; |
| |
| int emac_sgmii_config(struct platform_device *pdev, struct emac_adapter *adpt) |
| { |
| struct platform_device *sgmii_pdev = NULL; |
| struct emac_sgmii *phy = &adpt->phy; |
| struct resource *res; |
| int ret; |
| |
| if (has_acpi_companion(&pdev->dev)) { |
| struct device *dev; |
| |
| dev = device_find_child(&pdev->dev, &phy->initialize, |
| emac_sgmii_acpi_match); |
| |
| if (!dev) { |
| dev_err(&pdev->dev, "cannot find internal phy node\n"); |
| return -ENODEV; |
| } |
| |
| sgmii_pdev = to_platform_device(dev); |
| } else { |
| const struct of_device_id *match; |
| struct device_node *np; |
| |
| np = of_parse_phandle(pdev->dev.of_node, "internal-phy", 0); |
| if (!np) { |
| dev_err(&pdev->dev, "missing internal-phy property\n"); |
| return -ENODEV; |
| } |
| |
| sgmii_pdev = of_find_device_by_node(np); |
| if (!sgmii_pdev) { |
| dev_err(&pdev->dev, "invalid internal-phy property\n"); |
| return -ENODEV; |
| } |
| |
| match = of_match_device(emac_sgmii_dt_match, &sgmii_pdev->dev); |
| if (!match) { |
| dev_err(&pdev->dev, "unrecognized internal phy node\n"); |
| ret = -ENODEV; |
| goto error_put_device; |
| } |
| |
| phy->initialize = (emac_sgmii_function)match->data; |
| } |
| |
| phy->open = emac_sgmii_open; |
| phy->close = emac_sgmii_close; |
| phy->link_up = emac_sgmii_link_up; |
| phy->link_down = emac_sgmii_link_down; |
| |
| /* Base address is the first address */ |
| res = platform_get_resource(sgmii_pdev, IORESOURCE_MEM, 0); |
| if (!res) { |
| ret = -EINVAL; |
| goto error_put_device; |
| } |
| |
| phy->base = ioremap(res->start, resource_size(res)); |
| if (!phy->base) { |
| ret = -ENOMEM; |
| goto error_put_device; |
| } |
| |
| /* v2 SGMII has a per-lane digital digital, so parse it if it exists */ |
| res = platform_get_resource(sgmii_pdev, IORESOURCE_MEM, 1); |
| if (res) { |
| phy->digital = ioremap(res->start, resource_size(res)); |
| if (!phy->digital) { |
| ret = -ENOMEM; |
| goto error_unmap_base; |
| } |
| } |
| |
| ret = phy->initialize(adpt); |
| if (ret) |
| goto error; |
| |
| emac_sgmii_link_init(adpt); |
| |
| ret = platform_get_irq(sgmii_pdev, 0); |
| if (ret > 0) |
| phy->irq = ret; |
| |
| /* We've remapped the addresses, so we don't need the device any |
| * more. of_find_device_by_node() says we should release it. |
| */ |
| put_device(&sgmii_pdev->dev); |
| |
| return 0; |
| |
| error: |
| if (phy->digital) |
| iounmap(phy->digital); |
| error_unmap_base: |
| iounmap(phy->base); |
| error_put_device: |
| put_device(&sgmii_pdev->dev); |
| |
| return ret; |
| } |