Re: [PATCH 4/4] usb: musb: Add support for MediaTek musb controller
From: Min Guo
Date: Wed Jan 09 2019 - 07:31:32 EST
Hi Bin,
On Tue, 2019-01-08 at 09:44 -0600, Bin Liu wrote:
> Hi,
>
> On Thu, Dec 27, 2018 at 03:34:26PM +0800, min.guo@xxxxxxxxxxxx wrote:
> > From: Min Guo <min.guo@xxxxxxxxxxxx>
> >
> > This adds support for MediaTek musb controller in
> > host, peripheral and otg mode
> >
> > Signed-off-by: Min Guo <min.guo@xxxxxxxxxxxx>
> > Signed-off-by: Yonglong Wu <yonglong.wu@xxxxxxxxxxxx>
> > ---
> > drivers/usb/musb/Kconfig | 8 +-
> > drivers/usb/musb/Makefile | 1 +
> > drivers/usb/musb/mediatek.c | 562 +++++++++++++++++++++++++++++++++++++++++++
> > drivers/usb/musb/musb_core.c | 10 +
> > drivers/usb/musb/musb_core.h | 1 +
> > drivers/usb/musb/musb_dma.h | 1 +
> > drivers/usb/musb/musb_host.c | 79 ++++--
> > drivers/usb/musb/musb_regs.h | 6 +
> > drivers/usb/musb/musbhsdma.c | 34 ++-
> > 9 files changed, 671 insertions(+), 31 deletions(-)
> > create mode 100644 drivers/usb/musb/mediatek.c
> >
> > diff --git a/drivers/usb/musb/Kconfig b/drivers/usb/musb/Kconfig
> > index ad08895..540fc9f 100644
> > --- a/drivers/usb/musb/Kconfig
> > +++ b/drivers/usb/musb/Kconfig
> > @@ -115,6 +115,12 @@ config USB_MUSB_JZ4740
> > depends on USB_MUSB_GADGET
> > depends on USB_OTG_BLACKLIST_HUB
> >
> > +config USB_MUSB_MEDIATEK
> > + tristate "MediaTek platforms"
> > + depends on ARCH_MEDIATEK
>
> Please also add '|| COMPILE_TEST' to make testing easier.
Ok
> > + depends on NOP_USB_XCEIV
> > + depends on GENERIC_PHY
> > +
> > config USB_MUSB_AM335X_CHILD
> > tristate
> >
> > @@ -141,7 +147,7 @@ config USB_UX500_DMA
> >
> > config USB_INVENTRA_DMA
> > bool 'Inventra'
> > - depends on USB_MUSB_OMAP2PLUS
> > + depends on USB_MUSB_OMAP2PLUS || USB_MUSB_MEDIATEK
> > help
> > Enable DMA transfers using Mentor's engine.
> >
> > diff --git a/drivers/usb/musb/Makefile b/drivers/usb/musb/Makefile
> > index 3a88c79..63d82d0 100644
> > --- a/drivers/usb/musb/Makefile
> > +++ b/drivers/usb/musb/Makefile
> > @@ -24,6 +24,7 @@ obj-$(CONFIG_USB_MUSB_DA8XX) += da8xx.o
> > obj-$(CONFIG_USB_MUSB_UX500) += ux500.o
> > obj-$(CONFIG_USB_MUSB_JZ4740) += jz4740.o
> > obj-$(CONFIG_USB_MUSB_SUNXI) += sunxi.o
> > +obj-$(CONFIG_USB_MUSB_MEDIATEK) += mediatek.o
> >
> >
> > obj-$(CONFIG_USB_MUSB_AM335X_CHILD) += musb_am335x.o
> > diff --git a/drivers/usb/musb/mediatek.c b/drivers/usb/musb/mediatek.c
> > new file mode 100644
> > index 0000000..15a6460
> > --- /dev/null
> > +++ b/drivers/usb/musb/mediatek.c
>
> [snip]
> I will review this section later after we sorted out other things.
>
> > diff --git a/drivers/usb/musb/musb_core.c b/drivers/usb/musb/musb_core.c
> > index b7d5627..d60f76f 100644
> > --- a/drivers/usb/musb/musb_core.c
> > +++ b/drivers/usb/musb/musb_core.c
> > @@ -1028,6 +1028,16 @@ static void musb_disable_interrupts(struct musb *musb)
> > temp = musb_readb(mbase, MUSB_INTRUSB);
> > temp = musb_readw(mbase, MUSB_INTRTX);
> > temp = musb_readw(mbase, MUSB_INTRRX);
> > +
> > + /* MediaTek controller interrupt status is W1C */
>
> This W1C doesn't match to the MUSB Programming Guide that I have. Those
> registers are read-only.
> Is the difference due to the IP intergration in the mtk platforms? or is
> it a new version of the MUSB controller? If latter, what is the version?
This is difference due to the IP intergration in mtk platforms. W1C is
easy for CpdeViser debug.
> > + if (musb->ops->quirks & MUSB_MTK_QUIRKS) {
>
> Basically we don't want to use this type of platform specific quirks if
> possible, so let's try to not use it.
I will try my best to avoid using it.
> > + musb_writeb(mbase, MUSB_INTRUSB,
> > + musb_readb(mbase, MUSB_INTRUSB));
>
> For this clearing register bit operation, please create platform hooks
> musb_clearb() and musb_clearw() in struct musb_platform_ops instead,
> then follow how musb_readb() pointer is assigned in
> musb_init_controller() to use the W1C version for mtk platform.
I have tried implementing musb_readb(), musb_readw() interface with
interrupt status W1C function in struct musb_platform_ops. But this
interface will require a global variable to hold MAC basic address for
judgment, and then special handling of the interrupt state. A global
variable will make the driver work with only a single instance, so it
can't work on some MTK platforms which have two instances.
How about creating musb_clearb/w() as following:
void (*clearb)(void __iomem *addr, unsigned offset, u8 data);
void (*clearw)(void __iomem *addr, unsigned offset, u16 data);
> > + musb_writew(mbase, MUSB_INTRRX,
> > + musb_readw(mbase, MUSB_INTRRX));
> > + musb_writew(mbase, MUSB_INTRTX,
> > + musb_readw(mbase, MUSB_INTRTX));
> > + }
> > }
> >
> > static void musb_enable_interrupts(struct musb *musb)
> > diff --git a/drivers/usb/musb/musb_core.h b/drivers/usb/musb/musb_core.h
> > index 04203b7..1bf4e9a 100644
> > --- a/drivers/usb/musb/musb_core.h
> > +++ b/drivers/usb/musb/musb_core.h
> > @@ -138,6 +138,7 @@ enum musb_g_ep0_state {
> > */
> > struct musb_platform_ops {
> >
> > +#define MUSB_MTK_QUIRKS BIT(10)
> > #define MUSB_G_NO_SKB_RESERVE BIT(9)
> > #define MUSB_DA8XX BIT(8)
> > #define MUSB_PRESERVE_SESSION BIT(7)
> > diff --git a/drivers/usb/musb/musb_dma.h b/drivers/usb/musb/musb_dma.h
> > index 281e75d3..b218210 100644
> > --- a/drivers/usb/musb/musb_dma.h
> > +++ b/drivers/usb/musb/musb_dma.h
> > @@ -197,6 +197,7 @@ static inline void musb_dma_controller_destroy(struct dma_controller *d) { }
> > extern struct dma_controller *
> > musbhs_dma_controller_create(struct musb *musb, void __iomem *base);
> > extern void musbhs_dma_controller_destroy(struct dma_controller *c);
> > +extern irqreturn_t dma_controller_irq(int irq, void *private_data);
> >
> > extern struct dma_controller *
> > tusb_dma_controller_create(struct musb *musb, void __iomem *base);
> > diff --git a/drivers/usb/musb/musb_host.c b/drivers/usb/musb/musb_host.c
> > index b59ce9a..b1b0216 100644
> > --- a/drivers/usb/musb/musb_host.c
> > +++ b/drivers/usb/musb/musb_host.c
> > @@ -292,20 +292,73 @@ static inline void musb_save_toggle(struct musb_qh *qh, int is_in,
> > {
> > void __iomem *epio = qh->hw_ep->regs;
> > u16 csr;
> > + struct musb *musb = qh->hw_ep->musb;
> >
> > /*
> > * FIXME: the current Mentor DMA code seems to have
> > * problems getting toggle correct.
> > */
> >
> > - if (is_in)
> > - csr = musb_readw(epio, MUSB_RXCSR) & MUSB_RXCSR_H_DATATOGGLE;
> > - else
> > - csr = musb_readw(epio, MUSB_TXCSR) & MUSB_TXCSR_H_DATATOGGLE;
> > + /* MediaTek controller has private toggle register */
>
> only one toggle register for all endpoints? how does it handle
> difference toggle values for different endpoints?
MediaTek controller has separate registers to describe TX/RX toggle.
> > + if (musb->ops->quirks & MUSB_MTK_QUIRKS) {
> > + u16 toggle;
> > + u8 epnum = qh->hw_ep->epnum;
> > +
> > + if (is_in)
> > + toggle = musb_readl(musb->mregs, MUSB_RXTOG);
>
> should use musb_readw() instead? MUSB_RXTOG seems to be 16bit.
Ok
> > + else
> > + toggle = musb_readl(musb->mregs, MUSB_TXTOG);
> > +
> > + csr = toggle & (1 << epnum);
> > + } else {
> > + if (is_in)
> > + csr = musb_readw(epio, MUSB_RXCSR)
> > + & MUSB_RXCSR_H_DATATOGGLE;
> > + else
> > + csr = musb_readw(epio, MUSB_TXCSR)
> > + & MUSB_TXCSR_H_DATATOGGLE;
>
> Does this logic still work for the mtk platform even if it has its own
> private toggle register? If so, we don't need to change here.
Sorry, this logic can not work on mtk platform, bit
MUSB_RXCSR_H_DATATOGGLE and MUSB_TXCSR_H_DATATOGGLE are used for other
function.
> If not, let's try to not use this quirk flag. Please create a hook
> musb_platform_get_toggle() in struct musb_platform_ops.
Does the method of implement musb_platform_get_toggle() is prepare
musb_default_get_toggle with common function, then follow how
musb_readb() pointer is assigned in musb_init_controller()?
How about creating musb_platform_get_toggle() as following:
u16 (*get_toggle)(struct musb* musb, struct musb_qh *qh, int is_in);
> > + }
> >
> > usb_settoggle(urb->dev, qh->epnum, !is_in, csr ? 1 : 0);
> > }
> >
> > +static inline u16 musb_set_toggle(struct musb_qh *qh, int is_in,
> > + struct urb *urb)
> > +{
> > + u16 csr = 0;
> > + u16 toggle = 0;
> > + struct musb *musb = qh->hw_ep->musb;
> > + u8 epnum = qh->hw_ep->epnum;
> > +
> > + toggle = usb_gettoggle(urb->dev, qh->epnum, !is_in);
> > +
> > + /* MediaTek controller has private toggle register */
> > + if (musb->ops->quirks & MUSB_MTK_QUIRKS) {
> > + if (is_in) {
> > + musb_writel(musb->mregs, MUSB_RXTOGEN, (1 << epnum));
> > + musb_writel(musb->mregs, MUSB_RXTOG, (toggle << epnum));
> > + } else {
> > + musb_writel(musb->mregs, MUSB_TXTOGEN, (1 << epnum));
> > + musb_writel(musb->mregs, MUSB_TXTOG, (toggle << epnum));
> > + }
> > + } else {
> > + if (is_in) {
> > + if (toggle)
> > + csr = MUSB_RXCSR_H_WR_DATATOGGLE
> > + | MUSB_RXCSR_H_DATATOGGLE;
> > + else
> > + csr = 0;
> > + } else {
> > + if (toggle)
> > + csr |= MUSB_TXCSR_H_WR_DATATOGGLE
> > + | MUSB_TXCSR_H_DATATOGGLE;
> > + else
> > + csr |= MUSB_TXCSR_CLRDATATOG;
> > + }
> > + }
> > + return csr;
>
> Please create a seperate patch for this musb_set_toggle() without adding
> the mtk logic. It is a nice cleanup.
Does this like get toggle implementation, create a hook
musb_platform_set_toggle() in struct musb_platform_ops?
> > +}
> > +
> > /*
> > * Advance this hardware endpoint's queue, completing the specified URB and
> > * advancing to either the next URB queued to that qh, or else invalidating
> > @@ -772,13 +825,8 @@ static void musb_ep_program(struct musb *musb, u8 epnum,
> > );
> > csr |= MUSB_TXCSR_MODE;
> >
> > - if (!hw_ep->tx_double_buffered) {
> > - if (usb_gettoggle(urb->dev, qh->epnum, 1))
> > - csr |= MUSB_TXCSR_H_WR_DATATOGGLE
> > - | MUSB_TXCSR_H_DATATOGGLE;
> > - else
> > - csr |= MUSB_TXCSR_CLRDATATOG;
> > - }
> > + if (!hw_ep->tx_double_buffered)
> > + csr |= musb_set_toggle(qh, !is_out, urb);
> >
> > musb_writew(epio, MUSB_TXCSR, csr);
> > /* REVISIT may need to clear FLUSHFIFO ... */
> > @@ -860,17 +908,12 @@ static void musb_ep_program(struct musb *musb, u8 epnum,
> >
> > /* IN/receive */
> > } else {
> > - u16 csr;
> > + u16 csr = 0;
> >
> > if (hw_ep->rx_reinit) {
> > musb_rx_reinit(musb, qh, epnum);
> > + csr |= musb_set_toggle(qh, !is_out, urb);
> >
> > - /* init new state: toggle and NYET, maybe DMA later */
> > - if (usb_gettoggle(urb->dev, qh->epnum, 0))
> > - csr = MUSB_RXCSR_H_WR_DATATOGGLE
> > - | MUSB_RXCSR_H_DATATOGGLE;
> > - else
> > - csr = 0;
> > if (qh->type == USB_ENDPOINT_XFER_INT)
> > csr |= MUSB_RXCSR_DISNYET;
> >
> > diff --git a/drivers/usb/musb/musb_regs.h b/drivers/usb/musb/musb_regs.h
> > index 5cd7264..ffbe267 100644
> > --- a/drivers/usb/musb/musb_regs.h
> > +++ b/drivers/usb/musb/musb_regs.h
> > @@ -273,6 +273,12 @@
> > #define MUSB_RXHUBADDR 0x06
> > #define MUSB_RXHUBPORT 0x07
> >
> > +/* MediaTek controller toggle enable and status reg */
> > +#define MUSB_RXTOG 0x80
> > +#define MUSB_RXTOGEN 0x82
> > +#define MUSB_TXTOG 0x84
> > +#define MUSB_TXTOGEN 0x86
>
> Again, these offsets are for different registers in the MUSB version I
> have, please let me know if you have different version of the MUSB IP.
Sorry, these are MediaTek controller private registers used for control
toggle.
> > +
> > static inline u8 musb_read_configdata(void __iomem *mbase)
> > {
> > musb_writeb(mbase, MUSB_INDEX, 0);
> > diff --git a/drivers/usb/musb/musbhsdma.c b/drivers/usb/musb/musbhsdma.c
> > index 824adcb..c545475 100644
> > --- a/drivers/usb/musb/musbhsdma.c
> > +++ b/drivers/usb/musb/musbhsdma.c
> > @@ -263,7 +263,7 @@ static int dma_channel_abort(struct dma_channel *channel)
> > return 0;
> > }
> >
> > -static irqreturn_t dma_controller_irq(int irq, void *private_data)
> > +irqreturn_t dma_controller_irq(int irq, void *private_data)
> > {
> > struct musb_dma_controller *controller = private_data;
> > struct musb *musb = controller->private_data;
> > @@ -285,6 +285,8 @@ static irqreturn_t dma_controller_irq(int irq, void *private_data)
> > spin_lock_irqsave(&musb->lock, flags);
> >
> > int_hsdma = musb_readb(mbase, MUSB_HSDMA_INTR);
> > + if (musb->ops->quirks & MUSB_MTK_QUIRKS)
> > + musb_writeb(musb->mregs, MUSB_HSDMA_INTR, int_hsdma);
>
> you can use musb_clearb() defined above to get rid of this quirk.
OK.
> >
> > if (!int_hsdma) {
> > musb_dbg(musb, "spurious DMA irq");
> > @@ -377,15 +379,17 @@ static irqreturn_t dma_controller_irq(int irq, void *private_data)
> > spin_unlock_irqrestore(&musb->lock, flags);
> > return retval;
> > }
> > +EXPORT_SYMBOL_GPL(dma_controller_irq);
> >
> > void musbhs_dma_controller_destroy(struct dma_controller *c)
> > {
> > struct musb_dma_controller *controller = container_of(c,
> > struct musb_dma_controller, controller);
> > + struct musb *musb = controller->private_data;
> >
> > dma_controller_stop(controller);
> >
> > - if (controller->irq)
> > + if (!(musb->ops->quirks & MUSB_MTK_QUIRKS) && controller->irq)
> > free_irq(controller->irq, c);
> >
> > kfree(controller);
> > @@ -398,11 +402,15 @@ struct dma_controller *musbhs_dma_controller_create(struct musb *musb,
> > struct musb_dma_controller *controller;
> > struct device *dev = musb->controller;
> > struct platform_device *pdev = to_platform_device(dev);
> > - int irq = platform_get_irq_byname(pdev, "dma");
> > + int irq = -1;
> >
> > - if (irq <= 0) {
> > - dev_err(dev, "No DMA interrupt line!\n");
> > - return NULL;
> > + if (!(musb->ops->quirks & MUSB_MTK_QUIRKS)) {
> > + irq = platform_get_irq_byname(pdev, "dma");
> > +
> > + if (irq < 0) {
> > + dev_err(dev, "No DMA interrupt line!\n");
> > + return NULL;
> > + }
> > }
>
> Please create musbhs_dma_controller_destroy_noirq() for your platform to
> not use the quirk.
OK.
> >
> > controller = kzalloc(sizeof(*controller), GFP_KERNEL);
> > @@ -418,15 +426,17 @@ struct dma_controller *musbhs_dma_controller_create(struct musb *musb,
> > controller->controller.channel_program = dma_channel_program;
> > controller->controller.channel_abort = dma_channel_abort;
> >
> > - if (request_irq(irq, dma_controller_irq, 0,
> > + if (!(musb->ops->quirks & MUSB_MTK_QUIRKS)) {
> > + if (request_irq(irq, dma_controller_irq, 0,
> > dev_name(musb->controller), &controller->controller)) {
> > - dev_err(dev, "request_irq %d failed!\n", irq);
> > - musb_dma_controller_destroy(&controller->controller);
> > + dev_err(dev, "request_irq %d failed!\n", irq);
> > + musb_dma_controller_destroy(&controller->controller);
> >
> > - return NULL;
> > - }
> > + return NULL;
> > + }
> >
> > - controller->irq = irq;
> > + controller->irq = irq;
> > + }
> >
> > return &controller->controller;
> > }
>
> Same here, create musbhs_dma_controller_create_noirq(). Then use both
> new API for the mtk glue driver.
OK.
> Regards,
> -Bin.