From 8f140b407f3be04e7202be9aa0cfef3006d14c9f Mon Sep 17 00:00:00 2001 From: Arthur Jones Date: Thu, 10 May 2007 12:10:49 -0700 Subject: [PATCH] IB/ipath: Shadow the gpio_mask register Once upon a time, GPIO interrupts were rare. But then a chip bug in the waldo series forced the use of a GPIO interrupt to signal packet reception. This greatly increased the frequency of GPIO interrupts which have the gpio_mask bits set on the waldo chips. Other bits in the gpio_status register are used for I2C clock and data lines, these bits are usually on. An "unlikely" annotation leftover from the old days was improperly applied to these bits, and an unnecessary chip mmio read was being accessed in the interrupt fast path on waldo. Remove the stagnant unlikely annotation in the interrupt handler and keep a shadow copy of the gpio_mask register to avoid the slow mmio read when testing for interruptable GPIO bits. Signed-off-by: Arthur Jones Signed-off-by: Roland Dreier --- drivers/infiniband/hw/ipath/ipath_iba6120.c | 7 +++---- drivers/infiniband/hw/ipath/ipath_intr.c | 7 +++---- drivers/infiniband/hw/ipath/ipath_kernel.h | 2 ++ drivers/infiniband/hw/ipath/ipath_verbs.c | 12 ++++++------ 4 files changed, 14 insertions(+), 14 deletions(-) diff --git a/drivers/infiniband/hw/ipath/ipath_iba6120.c b/drivers/infiniband/hw/ipath/ipath_iba6120.c index 1b9c30857754..4e2e3dfeb2c8 100644 --- a/drivers/infiniband/hw/ipath/ipath_iba6120.c +++ b/drivers/infiniband/hw/ipath/ipath_iba6120.c @@ -747,7 +747,6 @@ static void ipath_pe_quiet_serdes(struct ipath_devdata *dd) static int ipath_pe_intconfig(struct ipath_devdata *dd) { - u64 val; u32 chiprev; /* @@ -760,9 +759,9 @@ static int ipath_pe_intconfig(struct ipath_devdata *dd) if ((chiprev & INFINIPATH_R_CHIPREVMINOR_MASK) > 1) { /* Rev2+ reports extra errors via internal GPIO pins */ dd->ipath_flags |= IPATH_GPIO_ERRINTRS; - val = ipath_read_kreg64(dd, dd->ipath_kregs->kr_gpio_mask); - val |= IPATH_GPIO_ERRINTR_MASK; - ipath_write_kreg( dd, dd->ipath_kregs->kr_gpio_mask, val); + dd->ipath_gpio_mask |= IPATH_GPIO_ERRINTR_MASK; + ipath_write_kreg(dd, dd->ipath_kregs->kr_gpio_mask, + dd->ipath_gpio_mask); } return 0; } diff --git a/drivers/infiniband/hw/ipath/ipath_intr.c b/drivers/infiniband/hw/ipath/ipath_intr.c index 45d033169c6e..a90d3b5699c4 100644 --- a/drivers/infiniband/hw/ipath/ipath_intr.c +++ b/drivers/infiniband/hw/ipath/ipath_intr.c @@ -1056,7 +1056,7 @@ irqreturn_t ipath_intr(int irq, void *data) gpiostatus &= ~(1 << IPATH_GPIO_PORT0_BIT); chk0rcv = 1; } - if (unlikely(gpiostatus)) { + if (gpiostatus) { /* * Some unexpected bits remain. If they could have * caused the interrupt, complain and clear. @@ -1065,9 +1065,8 @@ irqreturn_t ipath_intr(int irq, void *data) * GPIO interrupts, possibly on a "three strikes" * basis. */ - u32 mask; - mask = ipath_read_kreg32( - dd, dd->ipath_kregs->kr_gpio_mask); + const u32 mask = (u32) dd->ipath_gpio_mask; + if (mask & gpiostatus) { ipath_dbg("Unexpected GPIO IRQ bits %x\n", gpiostatus & mask); diff --git a/drivers/infiniband/hw/ipath/ipath_kernel.h b/drivers/infiniband/hw/ipath/ipath_kernel.h index e900c2593f44..12194f3dd8cc 100644 --- a/drivers/infiniband/hw/ipath/ipath_kernel.h +++ b/drivers/infiniband/hw/ipath/ipath_kernel.h @@ -397,6 +397,8 @@ struct ipath_devdata { unsigned long ipath_pioavailshadow[8]; /* shadow of kr_gpio_out, for rmw ops */ u64 ipath_gpio_out; + /* shadow the gpio mask register */ + u64 ipath_gpio_mask; /* kr_revision shadow */ u64 ipath_revision; /* diff --git a/drivers/infiniband/hw/ipath/ipath_verbs.c b/drivers/infiniband/hw/ipath/ipath_verbs.c index 12933e77c7e9..bb70845279b8 100644 --- a/drivers/infiniband/hw/ipath/ipath_verbs.c +++ b/drivers/infiniband/hw/ipath/ipath_verbs.c @@ -1387,13 +1387,12 @@ static int enable_timer(struct ipath_devdata *dd) * processing. */ if (dd->ipath_flags & IPATH_GPIO_INTR) { - u64 val; ipath_write_kreg(dd, dd->ipath_kregs->kr_debugportselect, 0x2074076542310ULL); /* Enable GPIO bit 2 interrupt */ - val = ipath_read_kreg64(dd, dd->ipath_kregs->kr_gpio_mask); - val |= (u64) (1 << IPATH_GPIO_PORT0_BIT); - ipath_write_kreg( dd, dd->ipath_kregs->kr_gpio_mask, val); + dd->ipath_gpio_mask |= (u64) (1 << IPATH_GPIO_PORT0_BIT); + ipath_write_kreg(dd, dd->ipath_kregs->kr_gpio_mask, + dd->ipath_gpio_mask); } init_timer(&dd->verbs_timer); @@ -1412,8 +1411,9 @@ static int disable_timer(struct ipath_devdata *dd) u64 val; /* Disable GPIO bit 2 interrupt */ val = ipath_read_kreg64(dd, dd->ipath_kregs->kr_gpio_mask); - val &= ~((u64) (1 << IPATH_GPIO_PORT0_BIT)); - ipath_write_kreg( dd, dd->ipath_kregs->kr_gpio_mask, val); + dd->ipath_gpio_mask &= ~((u64) (1 << IPATH_GPIO_PORT0_BIT)); + ipath_write_kreg(dd, dd->ipath_kregs->kr_gpio_mask, + dd->ipath_gpio_mask); /* * We might want to undo changes to debugportselect, * but how? -- 2.20.1