diff options
Diffstat (limited to 'drivers/usb/host/ehci-brcm.c')
| -rw-r--r-- | drivers/usb/host/ehci-brcm.c | 281 |
1 files changed, 281 insertions, 0 deletions
diff --git a/drivers/usb/host/ehci-brcm.c b/drivers/usb/host/ehci-brcm.c new file mode 100644 index 000000000..6a0f64c9e --- /dev/null +++ b/drivers/usb/host/ehci-brcm.c @@ -0,0 +1,281 @@ +// SPDX-License-Identifier: GPL-2.0 +/* Copyright (c) 2020, Broadcom */ + +#include <linux/clk.h> +#include <linux/dma-mapping.h> +#include <linux/err.h> +#include <linux/kernel.h> +#include <linux/io.h> +#include <linux/module.h> +#include <linux/platform_device.h> +#include <linux/usb.h> +#include <linux/usb/hcd.h> +#include <linux/iopoll.h> + +#include "ehci.h" + +#define hcd_to_ehci_priv(h) ((struct brcm_priv *)hcd_to_ehci(h)->priv) + +struct brcm_priv { + struct clk *clk; +}; + +/* + * ehci_brcm_wait_for_sof + * Wait for start of next microframe, then wait extra delay microseconds + */ +static inline void ehci_brcm_wait_for_sof(struct ehci_hcd *ehci, u32 delay) +{ + u32 frame_idx = ehci_readl(ehci, &ehci->regs->frame_index); + u32 val; + int res; + + /* Wait for next microframe (every 125 usecs) */ + res = readl_relaxed_poll_timeout(&ehci->regs->frame_index, val, + val != frame_idx, 1, 130); + if (res) + ehci_err(ehci, "Error waiting for SOF\n"); + udelay(delay); +} + +/* + * ehci_brcm_hub_control + * The EHCI controller has a bug where it can violate the SOF + * interval between the first two SOF's transmitted after resume + * if the resume occurs near the end of the microframe. This causees + * the controller to detect babble on the suspended port and + * will eventually cause the controller to reset the port. + * The fix is to Intercept the echi-hcd request to complete RESUME and + * align it to the start of the next microframe. + * See SWLINUX-1909 for more details + */ +static int ehci_brcm_hub_control( + struct usb_hcd *hcd, + u16 typeReq, + u16 wValue, + u16 wIndex, + char *buf, + u16 wLength) +{ + struct ehci_hcd *ehci = hcd_to_ehci(hcd); + int ports = HCS_N_PORTS(ehci->hcs_params); + u32 __iomem *status_reg; + unsigned long flags; + int retval, irq_disabled = 0; + u32 temp; + + temp = (wIndex & 0xff) - 1; + if (temp >= HCS_N_PORTS_MAX) /* Avoid index-out-of-bounds warning */ + temp = 0; + status_reg = &ehci->regs->port_status[temp]; + + /* + * RESUME is cleared when GetPortStatus() is called 20ms after start + * of RESUME + */ + if ((typeReq == GetPortStatus) && + (wIndex && wIndex <= ports) && + ehci->reset_done[wIndex-1] && + time_after_eq(jiffies, ehci->reset_done[wIndex-1]) && + (ehci_readl(ehci, status_reg) & PORT_RESUME)) { + + /* + * to make sure we are not interrupted until RESUME bit + * is cleared, disable interrupts on current CPU + */ + ehci_dbg(ehci, "SOF alignment workaround\n"); + irq_disabled = 1; + local_irq_save(flags); + ehci_brcm_wait_for_sof(ehci, 5); + } + retval = ehci_hub_control(hcd, typeReq, wValue, wIndex, buf, wLength); + if (irq_disabled) + local_irq_restore(flags); + return retval; +} + +static int ehci_brcm_reset(struct usb_hcd *hcd) +{ + struct ehci_hcd *ehci = hcd_to_ehci(hcd); + int len; + + ehci->big_endian_mmio = 1; + + ehci->caps = (void __iomem *)hcd->regs; + len = HC_LENGTH(ehci, ehci_readl(ehci, &ehci->caps->hc_capbase)); + ehci->regs = (void __iomem *)(hcd->regs + len); + + /* This fixes the lockup during reboot due to prior interrupts */ + ehci_writel(ehci, CMD_RESET, &ehci->regs->command); + mdelay(10); + + /* + * SWLINUX-1705: Avoid OUT packet underflows during high memory + * bus usage + */ + ehci_writel(ehci, 0x00800040, &ehci->regs->brcm_insnreg[1]); + ehci_writel(ehci, 0x00000001, &ehci->regs->brcm_insnreg[3]); + + return ehci_setup(hcd); +} + +static struct hc_driver __read_mostly ehci_brcm_hc_driver; + +static const struct ehci_driver_overrides brcm_overrides __initconst = { + .reset = ehci_brcm_reset, + .extra_priv_size = sizeof(struct brcm_priv), +}; + +static int ehci_brcm_probe(struct platform_device *pdev) +{ + struct device *dev = &pdev->dev; + struct resource *res_mem; + struct brcm_priv *priv; + struct usb_hcd *hcd; + int irq; + int err; + + err = dma_set_mask_and_coherent(dev, DMA_BIT_MASK(32)); + if (err) + return err; + + irq = platform_get_irq(pdev, 0); + if (irq <= 0) + return irq ? irq : -EINVAL; + + /* Hook the hub control routine to work around a bug */ + ehci_brcm_hc_driver.hub_control = ehci_brcm_hub_control; + + /* initialize hcd */ + hcd = usb_create_hcd(&ehci_brcm_hc_driver, dev, dev_name(dev)); + if (!hcd) + return -ENOMEM; + + platform_set_drvdata(pdev, hcd); + priv = hcd_to_ehci_priv(hcd); + + priv->clk = devm_clk_get_optional(dev, NULL); + if (IS_ERR(priv->clk)) { + err = PTR_ERR(priv->clk); + goto err_hcd; + } + + err = clk_prepare_enable(priv->clk); + if (err) + goto err_hcd; + + hcd->regs = devm_platform_get_and_ioremap_resource(pdev, 0, &res_mem); + if (IS_ERR(hcd->regs)) { + err = PTR_ERR(hcd->regs); + goto err_clk; + } + hcd->rsrc_start = res_mem->start; + hcd->rsrc_len = resource_size(res_mem); + err = usb_add_hcd(hcd, irq, IRQF_SHARED); + if (err) + goto err_clk; + + device_wakeup_enable(hcd->self.controller); + device_enable_async_suspend(hcd->self.controller); + + return 0; + +err_clk: + clk_disable_unprepare(priv->clk); +err_hcd: + usb_put_hcd(hcd); + + return err; +} + +static int ehci_brcm_remove(struct platform_device *dev) +{ + struct usb_hcd *hcd = platform_get_drvdata(dev); + struct brcm_priv *priv = hcd_to_ehci_priv(hcd); + + usb_remove_hcd(hcd); + clk_disable_unprepare(priv->clk); + usb_put_hcd(hcd); + return 0; +} + +static int __maybe_unused ehci_brcm_suspend(struct device *dev) +{ + int ret; + struct usb_hcd *hcd = dev_get_drvdata(dev); + struct brcm_priv *priv = hcd_to_ehci_priv(hcd); + bool do_wakeup = device_may_wakeup(dev); + + ret = ehci_suspend(hcd, do_wakeup); + if (ret) + return ret; + clk_disable_unprepare(priv->clk); + return 0; +} + +static int __maybe_unused ehci_brcm_resume(struct device *dev) +{ + struct usb_hcd *hcd = dev_get_drvdata(dev); + struct ehci_hcd *ehci = hcd_to_ehci(hcd); + struct brcm_priv *priv = hcd_to_ehci_priv(hcd); + int err; + + err = clk_prepare_enable(priv->clk); + if (err) + return err; + /* + * SWLINUX-1705: Avoid OUT packet underflows during high memory + * bus usage + */ + ehci_writel(ehci, 0x00800040, &ehci->regs->brcm_insnreg[1]); + ehci_writel(ehci, 0x00000001, &ehci->regs->brcm_insnreg[3]); + + ehci_resume(hcd, false); + + pm_runtime_disable(dev); + pm_runtime_set_active(dev); + pm_runtime_enable(dev); + + return 0; +} + +static SIMPLE_DEV_PM_OPS(ehci_brcm_pm_ops, ehci_brcm_suspend, + ehci_brcm_resume); + +static const struct of_device_id brcm_ehci_of_match[] = { + { .compatible = "brcm,ehci-brcm-v2", }, + { .compatible = "brcm,bcm7445-ehci", }, + {} +}; + +static struct platform_driver ehci_brcm_driver = { + .probe = ehci_brcm_probe, + .remove = ehci_brcm_remove, + .shutdown = usb_hcd_platform_shutdown, + .driver = { + .name = "ehci-brcm", + .pm = &ehci_brcm_pm_ops, + .of_match_table = brcm_ehci_of_match, + } +}; + +static int __init ehci_brcm_init(void) +{ + if (usb_disabled()) + return -ENODEV; + + ehci_init_driver(&ehci_brcm_hc_driver, &brcm_overrides); + return platform_driver_register(&ehci_brcm_driver); +} +module_init(ehci_brcm_init); + +static void __exit ehci_brcm_exit(void) +{ + platform_driver_unregister(&ehci_brcm_driver); +} +module_exit(ehci_brcm_exit); + +MODULE_ALIAS("platform:ehci-brcm"); +MODULE_DESCRIPTION("EHCI Broadcom STB driver"); +MODULE_AUTHOR("Al Cooper"); +MODULE_LICENSE("GPL"); |