This is part of the workaround for AM35x advisory Advisory 1.1.20.
The advisory says that the IPSS bridge can't handle 8 & 16 bit read
access. An 16bit read access to MUSB_INTRTXE results in an 32bit read
access which also reads INTRRX and therefore may lose interrupts.
This patch uses a shadow register of MUSB_INTRTXE so we only perform
write access to it.
Signed-off-by: Sebastian Andrzej Siewior <bigeasy@xxxxxxxxxxxxx>
---
drivers/usb/musb/musb_core.c | 8 +++++---
drivers/usb/musb/musb_gadget.c | 17 +++++++----------
drivers/usb/musb/musb_host.c | 8 +++-----
3 files changed, 15 insertions(+), 18 deletions(-)
diff --git a/drivers/usb/musb/musb_core.c b/drivers/usb/musb/musb_core.c
index ee04eae..b1dffea 100644
--- a/drivers/usb/musb/musb_core.c
+++ b/drivers/usb/musb/musb_core.c
@@ -670,7 +670,8 @@ static irqreturn_t musb_stage0_irq(struct musb *musb, u8 int_usb,
if (is_peripheral_active(musb)) {
/* REVISIT HNP; just force disconnect */
}
- musb_writew(musb->mregs, MUSB_INTRTXE, musb->epmask);
+ musb->context.intrtxe = musb->epmask;
+ musb_writew(musb->mregs, MUSB_INTRTXE, musb->context.intrtxe);
musb->context.intrrxe = musb->epmask & 0xfffe;
musb_writew(musb->mregs, MUSB_INTRRXE, musb->context.intrrxe);
musb_writeb(musb->mregs, MUSB_INTRUSBE, 0xf7);
@@ -893,7 +894,8 @@ void musb_start(struct musb *musb)
dev_dbg(musb->controller, "<== devctl %02x\n", devctl);
/* Set INT enable registers, enable interrupts */
- musb_writew(regs, MUSB_INTRTXE, musb->epmask);
+ musb->context.intrtxe = musb->epmask;
+ musb_writew(regs, MUSB_INTRTXE, musb->context.intrtxe);
musb->context.intrrxe = musb->epmask & 0xfffe;
musb_writew(musb->mregs, MUSB_INTRRXE, musb->context.intrrxe);
musb_writeb(regs, MUSB_INTRUSBE, 0xf7);
@@ -942,6 +944,7 @@ static void musb_generic_disable(struct musb *musb)
/* disable interrupts */
musb_writeb(mbase, MUSB_INTRUSBE, 0);
+ musb->context.intrtxe = 0;
musb_writew(mbase, MUSB_INTRTXE, 0);
musb->context.intrrxe = 0;
musb_writew(musb->mregs, MUSB_INTRRXE, musb->context.intrrxe);
@@ -2142,7 +2145,6 @@ static void musb_save_context(struct musb *musb)
musb->context.busctl = musb_read_ulpi_buscontrol(musb->mregs);
}
musb->context.power = musb_readb(musb_base, MUSB_POWER);
- musb->context.intrtxe = musb_readw(musb_base, MUSB_INTRTXE);
musb->context.intrusbe = musb_readb(musb_base, MUSB_INTRUSBE);
musb->context.index = musb_readb(musb_base, MUSB_INDEX);
musb->context.devctl = musb_readb(musb_base, MUSB_DEVCTL);
diff --git a/drivers/usb/musb/musb_gadget.c b/drivers/usb/musb/musb_gadget.c
index 629c2ea..cc24445 100644
--- a/drivers/usb/musb/musb_gadget.c
+++ b/drivers/usb/musb/musb_gadget.c
@@ -1079,7 +1079,6 @@ static int musb_gadget_enable(struct usb_ep *ep,
*/
musb_ep_select(mbase, epnum);
if (usb_endpoint_dir_in(desc)) {
- u16 int_txe = musb_readw(mbase, MUSB_INTRTXE);
if (hw_ep->is_shared_fifo)
musb_ep->is_in = 1;
@@ -1091,8 +1090,8 @@ static int musb_gadget_enable(struct usb_ep *ep,
goto fail;
}
- int_txe |= (1 << epnum);
- musb_writew(mbase, MUSB_INTRTXE, int_txe);
+ musb->context.intrtxe |= (1 << epnum);
+ musb_writew(mbase, MUSB_INTRTXE, musb->context.intrtxe);
/* REVISIT if can_bulk_split(), use by updating "tmp";
* likewise high bandwidth periodic tx
@@ -1218,9 +1217,8 @@ static int musb_gadget_disable(struct usb_ep *ep)
/* zero the endpoint sizes */
if (musb_ep->is_in) {
- u16 int_txe = musb_readw(musb->mregs, MUSB_INTRTXE);
- int_txe &= ~(1 << epnum);
- musb_writew(musb->mregs, MUSB_INTRTXE, int_txe);
+ musb->context.intrtxe &= ~(1 << epnum);
+ musb_writew(musb->mregs, MUSB_INTRTXE, musb->context.intrtxe);
musb_writew(epio, MUSB_TXMAXP, 0);
} else {
musb->context.intrrxe &= ~(1 << epnum);
@@ -1539,7 +1537,7 @@ static void musb_gadget_fifo_flush(struct usb_ep *ep)
void __iomem *epio = musb->endpoints[epnum].regs;
void __iomem *mbase;
unsigned long flags;
- u16 csr, int_txe;
+ u16 csr;
mbase = musb->mregs;
@@ -1547,8 +1545,7 @@ static void musb_gadget_fifo_flush(struct usb_ep *ep)
musb_ep_select(mbase, (u8) epnum);
/* disable interrupts */
- int_txe = musb_readw(mbase, MUSB_INTRTXE);
- musb_writew(mbase, MUSB_INTRTXE, int_txe & ~(1 << epnum));
+ musb_writew(mbase, MUSB_INTRTXE, musb->context.intrtxe & ~(1 << epnum));
if (musb_ep->is_in) {
csr = musb_readw(epio, MUSB_TXCSR);
@@ -1572,7 +1569,7 @@ static void musb_gadget_fifo_flush(struct usb_ep *ep)
}
/* re-enable interrupt */
- musb_writew(mbase, MUSB_INTRTXE, int_txe);
+ musb_writew(mbase, MUSB_INTRTXE, musb->context.intrtxe);
spin_unlock_irqrestore(&musb->lock, flags);
}
diff --git a/drivers/usb/musb/musb_host.c b/drivers/usb/musb/musb_host.c
index 79cb0af..34829fe 100644
--- a/drivers/usb/musb/musb_host.c
+++ b/drivers/usb/musb/musb_host.c
@@ -714,15 +714,13 @@ static void musb_ep_program(struct musb *musb, u8 epnum,
/* OUT/transmit/EP0 or IN/receive? */
if (is_out) {
u16 csr;
- u16 int_txe;
u16 load_count;
csr = musb_readw(epio, MUSB_TXCSR);
/* disable interrupt in case we flush */
- int_txe = musb_readw(mbase, MUSB_INTRTXE);
- musb_writew(mbase, MUSB_INTRTXE, int_txe & ~(1 << epnum));
-
+ musb_writew(mbase, MUSB_INTRTXE, musb->context.intrtxe &
+ ~(1 << epnum));
/* general endpoint setup */
if (epnum) {
/* flush all old state, set default */
@@ -807,7 +805,7 @@ static void musb_ep_program(struct musb *musb, u8 epnum,
}
/* re-enable interrupt */
- musb_writew(mbase, MUSB_INTRTXE, int_txe);
+ musb_writew(mbase, MUSB_INTRTXE, musb->context.intrtxe);
/* IN/receive */
} else {
--
1.7.9.1
--
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