Re: [PATCHv7 2.6.34-rc5 4/5] mxc: Add generic USB HWinitialization for MX51

[Sascha Hauer]

On Wed, Apr 21, 2010 at 10:13:14AM -0500, Dinh.Nguyen@xxxxxxxxxxxxx wrote:
> From: Dinh Nguyen <Dinh.Nguyen@xxxxxxxxxxxxx>
> 
> This patch adds USB HW initializiation code to /plat-mxc/ehci.c.
> 	-Stops and resets USB HW
> 	-Sets some specific PHY settings
> 	-Stop and restart the USB HW.
> Renames mxc_set_usbcontrol to mxc_initialize_usb_hw.
> The placing of the mxc_initialize_usb_hw needs to be before setting
> the USBMODE register to host, since a reset and restart is done in
> mxc_initialize_usb_hw.
> Adds new register bit defines for the USB HW on Freescale
> SoCs.
> 
> This patch applies to 2.6.34-rc5.
> 
> Signed-off-by: Dinh Nguyen <Dinh.Nguyen@xxxxxxxxxxxxx>
> Reviewed-by: Daniel Mack <daniel@xxxxxxxx>
> ---
>  arch/arm/plat-mxc/ehci.c                  |  149 ++++++++++++++++++++++++++++-
>  arch/arm/plat-mxc/include/mach/mxc_ehci.h |   58 +++++++++++-
>  drivers/usb/host/ehci-mxc.c               |   10 +-
>  3 files changed, 209 insertions(+), 8 deletions(-)
> 
> diff --git a/arch/arm/plat-mxc/ehci.c b/arch/arm/plat-mxc/ehci.c
> index cb0b638..b52335d 100644
> --- a/arch/arm/plat-mxc/ehci.c
> +++ b/arch/arm/plat-mxc/ehci.c
> @@ -1,5 +1,6 @@
>  /*
>   * Copyright (c) 2009 Daniel Mack <daniel@xxxxxxxx>
> + * Copyright (C) 2010 Freescale Semiconductor, Inc.
>   *
>   * This program is free software; you can redistribute it and/or modify it
>   * under the terms of the GNU General Public License as published by the
> @@ -18,6 +19,7 @@
>  
>  #include <linux/platform_device.h>
>  #include <linux/io.h>
> +#include <linux/delay.h>
>  
>  #include <mach/hardware.h>
>  #include <mach/mxc_ehci.h>
> @@ -50,7 +52,29 @@
>  #define MX35_H1_TLL_BIT		(1 << 5)
>  #define MX35_H1_USBTE_BIT	(1 << 4)
>  
> -int mxc_set_usbcontrol(int port, unsigned int flags)
> +/* This function is a version of David Brownell's handshake function in
> + * ehci-hcd.c. This function uses cpu_relax instead of udelay().
> + *
> + * @addr: Address of register
> + * @mask: bits to look at in result of read
> + * @done: value of those bits when handshake succeeds
> + * @timeout: timeout in count
> + *
> + * This function waits for certain bits in the HW to stick before moving
> + * on and provides a timeout in the case where those bits do not stick.
> + */
> +static inline int hw_handshake(u32 addr, u32 mask, int done, int timeout)
> +{
> +	while (--timeout && ((__raw_readl(addr) & mask) != done))
> +			cpu_relax();
> +
> +	if (timeout)
> +		return 0;
> +	else
> +		return -ETIMEDOUT;
> +}
> +
> +int mxc_initialize_usb_hw(int port, unsigned int flags)
>  {
>  	unsigned int v;
>  #ifdef CONFIG_ARCH_MX3
> @@ -186,9 +210,130 @@ int mxc_set_usbcontrol(int port, unsigned int flags)
>  		return 0;
>  	}
>  #endif /* CONFIG_MACH_MX27 */
> +#ifdef CONFIG_ARCH_MX51
> +	if (cpu_is_mx51()) {
> +		void __iomem *usb_base;
> +		u32 usbotg_base;
> +		u32 usbother_base;
> +		int ret = 0;
> +
> +		usb_base = ioremap(MX51_OTG_BASE_ADDR, SZ_4K);
> +
> +		switch (port) {
> +		case 0:	/* OTG port */
> +			usbotg_base = usb_base + USBOTG_OFFSET;
> +			break;
> +		case 1:	/* Host 1 port */
> +			usbotg_base = usb_base + USBH1_OFFSET;
> +			break;
> +		default:
> +			printk(KERN_ERR"%s no such port %d\n", __func__, port);
> +			ret = -ENOENT;
> +			goto error;
> +		}
> +		usbother_base = usb_base + USBOTHER_REGS_OFFSET;
> +
> +		/* Stop then Reset */
> +		v = __raw_readl(usbotg_base + USBCMD_OFFSET);
> +		v &= ~UCMD_RUN_STOP;
> +		__raw_writel(v, usbotg_base + USBCMD_OFFSET);
> +		ret = hw_handshake(usbotg_base + USBCMD_OFFSET, UCMD_RUN_STOP, 0, 500);
> +		if (ret) {
> +			printk(KERN_ERR "%s could not stop usb hardware\n", __func__);
> +			goto error;
> +		}
> +
> +		v = __raw_readl(usbotg_base + USBCMD_OFFSET);
> +		v |= UCMD_RESET;
> +		__raw_writel(v, usbotg_base + USBCMD_OFFSET);
> +		ret = hw_handshake(usbotg_base + USBCMD_OFFSET, UCMD_RESET, 0, 500);
> +		if (ret) {
> +			printk(KERN_ERR "%s could not reset usb hardware\n", __func__);
> +			goto error;
> +		}
> +
> +		switch (port) {
> +		case 0:	/*OTG port */
> +			if (flags & MXC_EHCI_INTERNAL_PHY) {
> +				v = __raw_readl(usbother_base + USB_PHY_CTR_FUNC_OFFSET);
> +
> +				if (flags & MXC_EHCI_POWER_PINS_ENABLED)
> +					v |= (USB_UTMI_PHYCTRL_OC_DIS | UCTRL_OPM); /* OC/USBPWR is not used */
> +				else
> +					v &= ~(USB_UTMI_PHYCTRL_OC_DIS | UCTRL_OPM); /* OC/USBPWR is used */
> +				__raw_writel(v, usbother_base + USB_PHY_CTR_FUNC_OFFSET);
> +
> +				v = __raw_readl(usbother_base + USBCTRL_OFFSET);
> +				if (flags & MXC_EHCI_WAKEUP_ENABLED)
> +					v |= UCTRL_OWIE;/* OTG wakeup enable */
> +				else
> +					v &= ~UCTRL_OWIE;/* OTG wakeup disable */
> +				__raw_writel(v, usbother_base + USBCTRL_OFFSET);
> +			}
> +			break;
> +		case 1:	/* Host 1 */
> +			/*Host ULPI */
> +			v = __raw_readl(usbother_base + USBCTRL_OFFSET);
> +			if (flags & MXC_EHCI_WAKEUP_ENABLED)
> +				v &= ~(UCTRL_H1WIE | UCTRL_H1UIE);/* HOST1 wakeup/ULPI intr disable */
> +			else
> +				v &= ~(UCTRL_H1WIE | UCTRL_H1UIE);/* HOST1 wakeup/ULPI intr disable */
> +
> +			if (flags & MXC_EHCI_POWER_PINS_ENABLED)
> +				v &= ~UCTRL_H1PM; /* HOST1 power mask used*/
> +			else
> +				v |= UCTRL_H1PM; /* HOST1 power mask used*/
> +			__raw_writel(v, usbother_base + USBCTRL_OFFSET);
> +
> +			v = __raw_readl(usbother_base + USB_PHY_CTR_FUNC_OFFSET);
> +			if (flags & MXC_EHCI_POWER_PINS_ENABLED)
> +				v &= ~USB_UH1_OC_DIS; /* OC is used */
> +			else
> +				v |= USB_UH1_OC_DIS; /* OC is not used */
> +			__raw_writel(v, usbother_base + USB_PHY_CTR_FUNC_OFFSET);
> +
> +			v = __raw_readl(usbotg_base + USBCMD_OFFSET);
> +			if (flags & MXC_EHCI_ITC_NO_THRESHOLD)
> +				/* Interrupt Threshold Control:Immediate (no threshold) */
> +				v &= UCMD_ITC_NO_THRESHOLD;
> +			__raw_writel(v, usbotg_base + USBCMD_OFFSET);
> +			break;
> +		}
> +
> +		/* need to reset the controller here so that the ID pin
> +		 * is correctly detected.
> +		 */
> +		/* Stop then Reset */
> +		v = __raw_readl(usbotg_base + USBCMD_OFFSET);
> +		v &= ~UCMD_RUN_STOP;
> +		__raw_writel(v, usbotg_base + USBCMD_OFFSET);
> +		ret = hw_handshake(usbotg_base + USBCMD_OFFSET, UCMD_RUN_STOP, 0, 500);
> +		if (ret) {
> +			printk(KERN_ERR "%s could not stop usb hardware\n", __func__);
> +			goto error;
> +		}
> +
> +		v = __raw_readl(usbotg_base + USBCMD_OFFSET);
> +		v |= UCMD_RESET;
> +		__raw_writel(v, usbotg_base + USBCMD_OFFSET);
> +		ret = hw_handshake(usbotg_base + USBCMD_OFFSET, UCMD_RESET, 0, 500);
> +		if (ret) {
> +			printk(KERN_ERR "%s could not reset usb hardware\n", __func__);
> +			goto error;
> +		}
> +
> +		/* allow controller to reset, and leave time for
> +		 * the ULPI transceiver to reset too.
> +		 */
> +		msleep(100);
> +error:
> +		iounmap(usb_base);
> +		return ret;
> +	}
> +#endif
>  	printk(KERN_WARNING
>  		"%s() unable to setup USBCONTROL for this CPU\n", __func__);
>  	return -EINVAL;
>  }
> -EXPORT_SYMBOL(mxc_set_usbcontrol);
> +EXPORT_SYMBOL(mxc_initialize_usb_hw);
>  
> diff --git a/arch/arm/plat-mxc/include/mach/mxc_ehci.h b/arch/arm/plat-mxc/include/mach/mxc_ehci.h
> index 4b9b836..0ec88bb 100644
> --- a/arch/arm/plat-mxc/include/mach/mxc_ehci.h
> +++ b/arch/arm/plat-mxc/include/mach/mxc_ehci.h
> @@ -1,6 +1,30 @@
>  #ifndef __INCLUDE_ASM_ARCH_MXC_EHCI_H
>  #define __INCLUDE_ASM_ARCH_MXC_EHCI_H
>  
> +#define USBOTG_OFFSET			0
> +#define USBH1_OFFSET			0x200
> +#define USBH2_OFFSET			0x400
> +#define USBH3_OFFSET			0x600
> +#define USBOTHER_REGS_OFFSET	0x800
> +
> +#define USBCMD_OFFSET			0x140
> +
> +#define ULPI_VIEWPORT_OFFSET	0x170
> +#define PORTSC_OFFSET		0x184
> +#define USBMODE_OFFSET		0x1a8
> +#define USBMODE_CM_HOST		3
> +
> +#define USBCTRL_OFFSET					0
> +#define USB_PHY_CTR_FUNC_OFFSET		0x8
> +#define USB_PHY_CTR_FUNC2_OFFSET		0xc
> +#define USB_CTRL_1_OFFSET				0x10
> +
> +
> +/* USBCMD */
> +#define UCMD_RUN_STOP           (1 << 0)        /* controller run/stop */
> +#define UCMD_RESET		(1 << 1)	/* controller reset */
> +#define UCMD_ITC_NO_THRESHOLD		(~(0xff << 16))	/* Interrupt Threshold Control */
> +
>  /* values for portsc field */
>  #define MXC_EHCI_PHY_LOW_POWER_SUSPEND	(1 << 23)
>  #define MXC_EHCI_FORCE_FS		(1 << 24)
> @@ -25,6 +49,38 @@
>  #define MXC_EHCI_INTERNAL_PHY		(1 << 7)
>  #define MXC_EHCI_IPPUE_DOWN		(1 << 8)
>  #define MXC_EHCI_IPPUE_UP		(1 << 9)
> +#define MXC_EHCI_WAKEUP_ENABLED	(1 << 10)
> +#define MXC_EHCI_ITC_NO_THRESHOLD	(1 << 11)
> +
> +/* USB_CTRL */
> +#define UCTRL_OUIE		(1 << 28)	/* OTG ULPI intr enable */
> +#define UCTRL_OWIE		(1 << 27)	/* OTG wakeup intr enable */
> +#define UCTRL_OBPVAL_RXDP	(1 << 26)	/* OTG RxDp status in bypass mode */
> +#define UCTRL_OBPVAL_RXDM	(1 << 25)	/* OTG RxDm status in bypass mode */
> +#define UCTRL_OPM		(1 << 24)	/* OTG power mask */
> +#define UCTRL_H1UIE		(1 << 12)	/* Host1 ULPI interrupt enable */
> +#define UCTRL_H1WIE		(1 << 11)	/* HOST1 wakeup intr enable */
> +#define UCTRL_H1PM		(1 <<  8)		/* HOST1 power mask */
> +
> +/* USB_PHY_CTRL_FUNC */
> +#define USB_UTMI_PHYCTRL_OC_DIS	(1 << 8)	/* OTG Disable Overcurrent Event */
> +#define USB_UH1_OC_DIS	(1 << 5)		/* UH1 Disable Overcurrent Event */
> +
> +/* USB_CTRL_1 */
> +#define USB_CTRL_UH1_EXT_CLK_EN			(1 << 25)
> +#define USB_CTRL_UH2_EXT_CLK_EN			(1 << 26)
> +
> +/* USB_PHY_CTRL_FUNC2*/
> +#define USB_UTMI_PHYCTRL2_PLLDIV_MASK		0x3
> +#define USB_UTMI_PHYCTRL2_PLLDIV_SHIFT		0
> +#define USB_UTMI_PHYCTRL2_HSDEVSEL_MASK		0x3
> +#define USB_UTMI_PHYCTRL2_HSDEVSEL_SHIFT	19
> +
> +#ifdef CONFIG_ARCH_MX51
> +#define	USB_PLLDIV_12_MHZ		0x00
> +#define	USB_PLL_DIV_19_2_MHZ	0x01
> +#define	USB_PLL_DIV_24_MHZ	0x02
> +#endif

Please have a general look over these defines. All defines in
include/mach should at least have a MXC_ prefix. Most of these are
i.MX51 specific and thus should have a MX51_ prefix.
I think many of these do not have to be here anyway since they are
already in drivers/usb/host/ehci-mxc.c, are unused, or are only used
in plat-mxc/ehci.c.

> @@ -191,6 +191,11 @@ static int ehci_mxc_drv_probe(struct platform_device *pdev)
>  		clk_enable(priv->ahbclk);
>  	}
>  
> +	/* setup specific usb hw */
> +	ret = mxc_initialize_usb_hw(pdev->id, pdata->flags);
> +	if (ret < 0)
> +		goto err_init;
> +
>  	/* set USBMODE to host mode */
>  	temp = readl(hcd->regs + USBMODE_OFFSET);
>  	writel(temp | USBMODE_CM_HOST, hcd->regs + USBMODE_OFFSET);
> @@ -199,11 +204,6 @@ static int ehci_mxc_drv_probe(struct platform_device *pdev)
>  	writel(pdata->portsc, hcd->regs + PORTSC_OFFSET);
>  	mdelay(10);
>  
> -	/* setup USBCONTROL. */
> -	ret = mxc_set_usbcontrol(pdev->id, pdata->flags);
> -	if (ret < 0)
> -		goto err_init;

Has somebody tested if this works on other i.MXs? I remember it was quite
difficult to get the correct order of initialization. I don't want to
break this.
We should at least make a seperate patch from it so that anybody
bisecting this only finds this change and not the i.MX51 support also
added in this patch.

Sascha


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