[PATCH 1/5] [POWERPC] sysdev: implement FSL GTM support
Anton Vorontsov
avorontsov at ru.mvista.com
Tue Apr 22 00:28:26 EST 2008
On Mon, Apr 21, 2008 at 08:03:31AM -0600, Grant Likely wrote:
> 2008/4/18 Anton Vorontsov <avorontsov at ru.mvista.com>:
> > GTM stands for General-purpose Timers Module and able to generate
> > timer{1,2,3,4} interrupts. These timers are used by the drivers that
> > need time precise interrupts (like for USB transactions scheduling for
> > the Freescale USB Host controller as found in some QE and CPM chips),
> > or these timers could be used as wakeup events from the CPU deep-sleep
> > mode.
>
> Comments below.
>
> > diff --git a/Documentation/powerpc/booting-without-of.txt b/Documentation/powerpc/booting-without-of.txt
> > index 4cc7800..827b630 100644
> > --- a/Documentation/powerpc/booting-without-of.txt
> > +++ b/Documentation/powerpc/booting-without-of.txt
> > @@ -57,7 +57,8 @@ Table of Contents
> > n) 4xx/Axon EMAC ethernet nodes
> > o) Xilinx IP cores
> > p) Freescale Synchronous Serial Interface
> > - q) USB EHCI controllers
> > + q) USB EHCI controllers
> > + r) Freescale General-purpose Timers Module
> >
> > VII - Marvell Discovery mv64[345]6x System Controller chips
> > 1) The /system-controller node
> > @@ -2825,6 +2826,35 @@ platforms are moved over to use the flattened-device-tree model.
> > big-endian;
> > };
> >
> > + r) Freescale General-purpose Timers Module
> > +
> > + Required properties:
> > + - compatible : should be "fsl,gtm" ("fsl,qe-gtm" in addition for QE
> > + GTMs or "fsl,cpm2-gtm" for CPM2 GTMs).
>
> I don't think this is specific enough. It is a very real possibility
> for Freescale to produce another part with a "general purpose timers
> module" that isn't register level compatible (and fsl,i2c is an
> example of what not to do). The compatible string should include the
> exact chip version. Newer parts can also claim compatibility with
> older ones.
Ok, I'll expand this to fsl,<cpu-specific>-gtm and
fsl,<cpu-specific>-{qe,cpm2}-gtm.
> Defining a 'generic' compatible value is also known as "making stuff up". :-)
>
> > + - reg : should contain gtm registers location and length (0x40).
> > + - interrupts : should contain four interrupts.
> > + - interrupt-parent : interrupt source phandle.
> > + - clock-frequency : specifies the frequency driving the timer.
> > +
> > + Example:
> > +
> > + timer at 500 {
> > + compatible = "fsl,gtm";
> > + reg = <0x500 0x40>;
> > + interrupts = <90 8 78 8 84 8 72 8>;
> > + interrupt-parent = <&ipic>;
> > + /* filled by u-boot */
> > + clock-frequency = <0>;
> > + };
> > +
> > + timer at 440 {
> > + compatible = "fsl,qe-gtm", "fsl,gtm";
> > + reg = <0x440 0x40>;
> > + interrupts = <12 13 14 15>;
> > + interrupt-parent = <&qeic>;
> > + /* filled by u-boot */
> > + clock-frequency = <0>;
> > + };
> >
> > VII - Marvell Discovery mv64[345]6x System Controller chips
> > ===========================================================
> > diff --git a/arch/powerpc/Kconfig b/arch/powerpc/Kconfig
> > index 7f2f126..ad874e4 100644
> > --- a/arch/powerpc/Kconfig
> > +++ b/arch/powerpc/Kconfig
> > @@ -525,6 +525,11 @@ config FSL_LBC
> > help
> > Freescale Localbus support
> >
> > +config FSL_GTM
> > + bool
> > + help
> > + Freescale General-purpose Timers support
> > +
> > # Yes MCA RS/6000s exist but Linux-PPC does not currently support any
> > config MCA
> > bool
> > diff --git a/arch/powerpc/sysdev/Makefile b/arch/powerpc/sysdev/Makefile
> > index 6d386d0..9d3ddd2 100644
> > --- a/arch/powerpc/sysdev/Makefile
> > +++ b/arch/powerpc/sysdev/Makefile
> > @@ -13,6 +13,7 @@ obj-$(CONFIG_MMIO_NVRAM) += mmio_nvram.o
> > obj-$(CONFIG_FSL_SOC) += fsl_soc.o
> > obj-$(CONFIG_FSL_PCI) += fsl_pci.o
> > obj-$(CONFIG_FSL_LBC) += fsl_lbc.o
> > +obj-$(CONFIG_FSL_GTM) += fsl_gtm.o
> > obj-$(CONFIG_RAPIDIO) += fsl_rio.o
> > obj-$(CONFIG_TSI108_BRIDGE) += tsi108_pci.o tsi108_dev.o
> > obj-$(CONFIG_QUICC_ENGINE) += qe_lib/
> > diff --git a/arch/powerpc/sysdev/fsl_gtm.c b/arch/powerpc/sysdev/fsl_gtm.c
> > new file mode 100644
> > index 0000000..d29df56
> > --- /dev/null
> > +++ b/arch/powerpc/sysdev/fsl_gtm.c
> > @@ -0,0 +1,365 @@
> > +/*
> > + * Freescale General-purpose Timers Module
> > + *
> > + * Copyright (c) Freescale Semicondutor, Inc. 2006.
> > + * Shlomi Gridish <gridish at freescale.com>
> > + * Jerry Huang <Chang-Ming.Huang at freescale.com>
> > + * Copyright (c) MontaVista Software, Inc. 2008.
> > + * Anton Vorontsov <avorontsov at ru.mvista.com>
> > + *
> > + * 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
> > + * Free Software Foundation; either version 2 of the License, or (at your
> > + * option) any later version.
> > + */
> > +
> > +#include <linux/kernel.h>
> > +#include <linux/errno.h>
> > +#include <linux/io.h>
> > +#include <linux/of.h>
> > +#include <linux/spinlock.h>
> > +#include <linux/bitops.h>
> > +#include <asm/fsl_gtm.h>
> > +
> > +/**
> > + * gtm_get_timer - request GTM timer to use it with the rest of GTM API
> > + * @width: timer width (only 16 bits wide timers implemented so far)
> > + *
> > + * This function reserves GTM timer for later use. It returns gtm_timer
> > + * structure to use with the rest of GTM API, you should use timer->irq
> > + * to manage timer interrupt.
> > + */
> > +struct gtm_timer *gtm_get_timer(int width)
> > +{
> > + struct device_node *np;
> > + struct gtm *gtm = NULL;
> > + int i;
> > +
> > + if (width != 16)
> > + return ERR_PTR(-ENOSYS);
> > +
> > + for_each_compatible_node(np, NULL, "fsl,gtm") {
> > + if (!np->data) {
> > + WARN_ON(1);
> > + continue;
> > + }
> > + gtm = np->data;
> > +
> > + spin_lock_irq(>m->lock);
> > +
> > + for (i = 0; i < ARRAY_SIZE(gtm->timers); i++) {
> > + if (!gtm->timers[i].requested) {
> > + gtm->timers[i].requested = true;
> > + spin_unlock_irq(>m->lock);
> > + of_node_put(np);
> > + return >m->timers[i];
> > + }
> > + }
> > +
> > + spin_unlock_irq(>m->lock);
> > + }
> > +
> > + if (gtm)
> > + return ERR_PTR(-EBUSY);
> > + return ERR_PTR(-ENODEV);
> > +}
> > +EXPORT_SYMBOL(gtm_get_timer);
>
> This isn't a very efficient construct. You've already located all of
> the relevant nodes in the gtm_init() function. Searching the device
> tree is not efficient, so it should be avoided and only be performed
> once. Can you move the extraction of data from the tree to gtm_init()
> and only parse the drivers list of timers in this function?
Well, yes. I can create a list, and place all the GTMs in there.
> > +
> > +/**
> > + * gtm_get_specific_timer - request specific GTM timer
> > + * @gtm: specific GTM, pass here GTM's device_node->data
> > + * @timer: specific timer number, Timer1 is 0.
> > + * @width: timer width (only 16 bits wide timers implemented so far)
> > + *
> > + * This function reserves GTM timer for later use. It returns gtm_timer
> > + * structure to use with the rest of GTM API, you should use timer->irq
> > + * to manage timer interrupt.
> > + */
> > +struct gtm_timer *gtm_get_specific_timer(struct gtm *gtm, int timer, int width)
> > +{
> > + struct gtm_timer *ret = ERR_PTR(-EBUSY);
> > +
> > + if (width != 16)
> > + return ERR_PTR(-ENOSYS);
> > +
> > + spin_lock_irq(>m->lock);
> > +
> > + if (gtm->timers[timer].requested)
> > + goto out;
> > +
> > + ret = >m->timers[timer];
> > + ret->requested = true;
> > +
> > +out:
> > + spin_unlock_irq(>m->lock);
> > + return ret;
> > +}
> > +EXPORT_SYMBOL(gtm_get_specific_timer);
> > +
> > +/**
> > + * gtm_put_timer - release GTM timer
> > + * @width: timer width (only 16 bits wide timers implemented so far)
> > + *
> > + * This function releases GTM timer so others may request it.
> > + */
> > +void gtm_put_timer(struct gtm_timer *tmr)
> > +{
> > + spin_lock_irq(&tmr->gtm->lock);
> > +
> > + tmr->requested = false;
> > +
> > + spin_unlock_irq(&tmr->gtm->lock);
> > +}
> > +EXPORT_SYMBOL(gtm_put_timer);
> > +
> > +/*
> > + * This is back-end for the exported functions, it's used to reset single
> > + * timer in reference mode.
> > + */
> > +static int gtm_reset_ref_timer16(struct gtm_timer *tmr, int frequency,
> > + int reference_value, bool free_run)
> > +{
> > + struct gtm *gtm = tmr->gtm;
> > + int num = tmr - >m->timers[0];
> > + unsigned int prescaler;
> > + u8 iclk = GTMDR_ICLK_ICLK;
> > + u8 psr;
> > + u8 sps;
> > + unsigned long flags;
> > + int max_prescaler = 256 * 256 * 16;
> > +
> > + /* CPM2 doesn't have primary prescaler */
> > + if (!tmr->gtpsr)
> > + max_prescaler /= 256;
> > +
> > + prescaler = gtm->clock / frequency;
> > + /*
> > + * We have two 8 bit prescalers -- primary and secondary (psr, sps),
> > + * plus "slow go" mode (clk / 16). So, total prescale value is
> > + * 16 * (psr + 1) * (sps + 1). Though, for CPM2 GTMs we losing psr.
> > + */
> > + if (prescaler > max_prescaler)
> > + return -EINVAL;
> > +
> > + if (prescaler > max_prescaler / 16) {
> > + iclk = GTMDR_ICLK_SLGO;
> > + prescaler /= 16;
> > + }
> > +
> > + if (prescaler <= 256) {
> > + psr = 0;
> > + sps = prescaler - 1;
> > + } else {
> > + psr = 256 - 1;
> > + sps = prescaler / 256 - 1;
> > + }
> > +
> > + spin_lock_irqsave(>m->lock, flags);
> > +
> > + /*
> > + * Properly reset timers: stop, reset, set up prescalers, reference
> > + * value and clear event register.
> > + */
> > + clrsetbits_8(tmr->gtcfr, ~(GTCFR_STP(num) | GTCFR_RST(num)),
> > + GTCFR_STP(num) | GTCFR_RST(num));
> > +
> > + setbits8(tmr->gtcfr, GTCFR_STP(num));
> > +
> > + if (tmr->gtpsr)
> > + out_be16(tmr->gtpsr, psr);
> > + clrsetbits_be16(tmr->gtmdr, 0xFFFF, iclk | GTMDR_SPS(sps) |
> > + GTMDR_ORI | (free_run ? GTMDR_FRR : 0));
> > + out_be16(tmr->gtcnr, 0);
> > + out_be16(tmr->gtrfr, reference_value);
> > + out_be16(tmr->gtevr, 0xFFFF);
> > +
> > + /* Let it be. */
> > + clrbits8(tmr->gtcfr, GTCFR_STP(num));
> > +
> > + spin_unlock_irqrestore(>m->lock, flags);
> > +
> > + return 0;
> > +}
> > +/**
> > + * gtm_reset_timer16 - reset 16 bit timer with arbitrary precision
> > + * @tmr: pointer to the gtm_timer structure obtained from gtm_get_timer
> > + * @usec: timer interval in microseconds
> > + * @reload: if set, the timer will reset upon expiry rather than
> > + * continue running free.
> > + *
> > + * This function (re)sets the GTM timer so that it counts up to the requested
> > + * interval value, and fires the interrupt when the value is reached. This
> > + * function will reduce the precision of the timer as needed in order for the
> > + * requested timeout to fit in a 16-bit register.
> > + */
> > +int gtm_reset_timer16(struct gtm_timer *tmr, unsigned long usec, bool reload)
> > +{
> > + /* quite obvious, frequency which is enough for µSec precision */
> > + int freq = 1000000;
> > + unsigned int bit;
> > +
> > + bit = fls_long(usec);
> > + if (bit > 15) {
> > + freq >>= bit - 15;
> > + usec >>= bit - 15;
> > + }
> > +
> > + if (!freq)
> > + return -EINVAL;
> > +
> > + return gtm_reset_ref_timer16(tmr, freq, usec, reload);
> > +}
> > +EXPORT_SYMBOL(gtm_reset_timer16);
> > +
> > +/**
> > + * gtm_reset_utimer16 - reset 16 bits timer
> > + * @tmr: pointer to the gtm_timer structure obtained from gtm_get_timer
> > + * @usec: timer interval in microseconds
> > + * @reload: if set, the timer will reset upon expiry rather than
> > + * continue running free.
> > + *
> > + * This function (re)sets GTM timer so that it counts up to the requested
> > + * interval value, and fires the interrupt when the value is reached. If reload
> > + * flag was set, timer will also reset itself upon reference value, otherwise
> > + * it continues to increment.
> > + */
> > +int gtm_reset_utimer16(struct gtm_timer *tmr, u16 usec, bool reload)
> > +{
> > + /* quite obvious, frequency which is enough for µSec precision */
> > + const int freq = 1000000;
> > +
> > + /*
> > + * We can lower the frequency (and probably power consumption) by
> > + * dividing both frequency and usec by 2 until there is no remainder.
> > + * But we won't bother with this unless savings are measured, so just
> > + * run the timer as is.
> > + */
> > +
> > + return gtm_reset_ref_timer16(tmr, freq, usec, reload);
> > +}
> > +EXPORT_SYMBOL(gtm_reset_utimer16);
> > +
> > +/**
> > + * gtm_stop_timer16 - stop single timer
> > + * @tmr: pointer to the gtm_timer structure obtained from gtm_get_timer
> > + *
> > + * This function simply stops the GTM timer.
> > + */
> > +void gtm_stop_timer16(struct gtm_timer *tmr)
> > +{
> > + struct gtm *gtm = tmr->gtm;
> > + int num = tmr - >m->timers[0];
> > + unsigned long flags;
> > +
> > + spin_lock_irqsave(>m->lock, flags);
> > +
> > + setbits8(tmr->gtcfr, GTCFR_STP(num));
> > + out_be16(tmr->gtevr, 0xFFFF);
> > +
> > + spin_unlock_irqrestore(>m->lock, flags);
> > +}
> > +EXPORT_SYMBOL(gtm_stop_timer16);
> > +
> > +static void __init gtm_set_shortcuts(struct device_node *np,
> > + struct gtm_timer *timers,
> > + struct gtm_timers_regs __iomem *regs)
> > +{
> > + /*
> > + * Yeah, I don't like this either, but timers' registers a bit messed,
> > + * so we have to provide shortcuts to write timer independent code.
> > + * Alternative option is to create gt*() accessors, but that will be
> > + * even uglier and cryptic.
> > + */
> > + timers[0].gtcfr = ®s->gtcfr1;
> > + timers[0].gtmdr = ®s->gtmdr1;
> > + timers[0].gtcnr = ®s->gtcnr1;
> > + timers[0].gtrfr = ®s->gtrfr1;
> > + timers[0].gtevr = ®s->gtevr1;
> > +
> > + timers[1].gtcfr = ®s->gtcfr1;
> > + timers[1].gtmdr = ®s->gtmdr2;
> > + timers[1].gtcnr = ®s->gtcnr2;
> > + timers[1].gtrfr = ®s->gtrfr2;
> > + timers[1].gtevr = ®s->gtevr2;
> > +
> > + timers[2].gtcfr = ®s->gtcfr2;
> > + timers[2].gtmdr = ®s->gtmdr3;
> > + timers[2].gtcnr = ®s->gtcnr3;
> > + timers[2].gtrfr = ®s->gtrfr3;
> > + timers[2].gtevr = ®s->gtevr3;
> > +
> > + timers[3].gtcfr = ®s->gtcfr2;
> > + timers[3].gtmdr = ®s->gtmdr4;
> > + timers[3].gtcnr = ®s->gtcnr4;
> > + timers[3].gtrfr = ®s->gtrfr4;
> > + timers[3].gtevr = ®s->gtevr4;
> > +
> > + /* CPM2 doesn't have primary prescaler */
> > + if (!of_device_is_compatible(np, "fsl,cpm2-gtm")) {
> > + timers[0].gtpsr = ®s->gtpsr1;
> > + timers[1].gtpsr = ®s->gtpsr2;
> > + timers[2].gtpsr = ®s->gtpsr3;
> > + timers[3].gtpsr = ®s->gtpsr4;
> > + }
> > +}
> > +
> > +static int __init gtm_init(void)
> > +{
> > + struct device_node *np;
> > +
> > + for_each_compatible_node(np, NULL, "fsl,gtm") {
> > + int i;
> > + struct gtm *gtm;
> > + const u32 *clock;
> > + int size;
> > +
> > + gtm = kzalloc(sizeof(*gtm), GFP_KERNEL);
> > + if (!gtm) {
> > + pr_err("%s: unable to allocate memory\n",
> > + np->full_name);
> > + continue;
> > + }
> > +
> > + spin_lock_init(>m->lock);
> > +
> > + clock = of_get_property(np, "clock-frequency", &size);
> > + if (!clock || size != sizeof(*clock)) {
> > + pr_err("%s: no clock-frequency\n", np->full_name);
> > + goto err;
> > + }
> > + gtm->clock = *clock;
> > +
> > + for (i = 0; i < ARRAY_SIZE(gtm->timers); i++) {
> > + int ret;
> > + struct resource irq;
> > +
> > + ret = of_irq_to_resource(np, i, &irq);
> > + if (ret == NO_IRQ) {
> > + pr_err("%s: not enough interrupts specified\n",
> > + np->full_name);
> > + goto err;
> > + }
> > + gtm->timers[i].irq = irq.start;
> > + gtm->timers[i].gtm = gtm;
> > + }
> > +
> > + gtm->regs = of_iomap(np, 0);
> > + if (!gtm->regs) {
> > + pr_err("%s: unable to iomap registers\n",
> > + np->full_name);
> > + goto err;
> > + }
> > +
> > + gtm_set_shortcuts(np, gtm->timers, gtm->regs);
> > +
> > + /* We don't want to lose the node and its ->data */
> > + of_node_get(np);
> > + np->data = gtm;
> > +
> > + continue;
> > +err:
> > + kfree(gtm);
> > + }
> > + return 0;
> > +}
> > +arch_initcall(gtm_init);
> > diff --git a/include/asm-powerpc/fsl_gtm.h b/include/asm-powerpc/fsl_gtm.h
> > new file mode 100644
> > index 0000000..3eafb21
> > --- /dev/null
> > +++ b/include/asm-powerpc/fsl_gtm.h
> > @@ -0,0 +1,108 @@
> > +/*
> > + * Freescale General-purpose Timers Module
> > + *
> > + * Copyright (c) Freescale Semicondutor, Inc. 2006.
> > + * Shlomi Gridish <gridish at freescale.com>
> > + * Jerry Huang <Chang-Ming.Huang at freescale.com>
> > + * Copyright (c) MontaVista Software, Inc. 2008.
> > + * Anton Vorontsov <avorontsov at ru.mvista.com>
> > + *
> > + * 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
> > + * Free Software Foundation; either version 2 of the License, or (at your
> > + * option) any later version.
> > + */
> > +
> > +#ifndef __ASM_FSL_GTM_H
> > +#define __ASM_FSL_GTM_H
> > +
> > +#include <linux/types.h>
> > +#include <linux/spinlock.h>
> > +#include <linux/io.h>
> > +
> > +#define GTCFR_STP(x) ((x) & 1 ? 1 << 5 : 1 << 1)
> > +#define GTCFR_RST(x) ((x) & 1 ? 1 << 4 : 1 << 0)
> > +
> > +#define GTMDR_ICLK_MASK (3 << 1)
> > +#define GTMDR_ICLK_ICAS (0 << 1)
> > +#define GTMDR_ICLK_ICLK (1 << 1)
> > +#define GTMDR_ICLK_SLGO (2 << 1)
> > +#define GTMDR_FRR (1 << 3)
> > +#define GTMDR_ORI (1 << 4)
> > +#define GTMDR_SPS(x) ((x) << 8)
> > +
> > +struct gtm_timers_regs {
> > + u8 gtcfr1; /* Timer 1, Timer 2 global config register */
> > + u8 res0[0x3];
> > + u8 gtcfr2; /* Timer 3, timer 4 global config register */
> > + u8 res1[0xB];
> > + __be16 gtmdr1; /* Timer 1 mode register */
> > + __be16 gtmdr2; /* Timer 2 mode register */
> > + __be16 gtrfr1; /* Timer 1 reference register */
> > + __be16 gtrfr2; /* Timer 2 reference register */
> > + __be16 gtcpr1; /* Timer 1 capture register */
> > + __be16 gtcpr2; /* Timer 2 capture register */
> > + __be16 gtcnr1; /* Timer 1 counter */
> > + __be16 gtcnr2; /* Timer 2 counter */
> > + __be16 gtmdr3; /* Timer 3 mode register */
> > + __be16 gtmdr4; /* Timer 4 mode register */
> > + __be16 gtrfr3; /* Timer 3 reference register */
> > + __be16 gtrfr4; /* Timer 4 reference register */
> > + __be16 gtcpr3; /* Timer 3 capture register */
> > + __be16 gtcpr4; /* Timer 4 capture register */
> > + __be16 gtcnr3; /* Timer 3 counter */
> > + __be16 gtcnr4; /* Timer 4 counter */
> > + __be16 gtevr1; /* Timer 1 event register */
> > + __be16 gtevr2; /* Timer 2 event register */
> > + __be16 gtevr3; /* Timer 3 event register */
> > + __be16 gtevr4; /* Timer 4 event register */
> > + __be16 gtpsr1; /* Timer 1 prescale register */
> > + __be16 gtpsr2; /* Timer 2 prescale register */
> > + __be16 gtpsr3; /* Timer 3 prescale register */
> > + __be16 gtpsr4; /* Timer 4 prescale register */
> > + u8 res2[0x40];
> > +} __attribute__ ((packed));
> > +
> > +struct gtm_timer {
> > + unsigned int irq;
> > +
> > + struct gtm *gtm;
> > + bool requested;
> > + u8 __iomem *gtcfr;
> > + __be16 __iomem *gtmdr;
> > + __be16 __iomem *gtpsr;
> > + __be16 __iomem *gtcnr;
> > + __be16 __iomem *gtrfr;
> > + __be16 __iomem *gtevr;
> > +};
> > +
> > +struct gtm {
> > + unsigned int clock;
> > + struct gtm_timers_regs __iomem *regs;
> > + struct gtm_timer timers[4];
> > + spinlock_t lock;
> > +};
>
> Consider moving the register definitions and structures inside the .c
> file. This is all anonymous data as far as the caller is concerned.
> If the structures are only access inside the driver then you gain
> yourself a bit of safety by moving them.
Ok.
> > +
> > +extern struct gtm_timer *gtm_get_timer(int width);
> > +extern struct gtm_timer *gtm_get_specific_timer(struct gtm *gtm, int timer,
> > + int width);
> > +extern void gtm_put_timer(struct gtm_timer *tmr);
> > +extern int gtm_reset_timer16(struct gtm_timer *tmr, unsigned long usec,
> > + bool reload);
> > +extern int gtm_reset_utimer16(struct gtm_timer *tmr, u16 usec, bool reload);
> > +extern void gtm_stop_timer16(struct gtm_timer *tmr);
> > +
> > +/**
> > + * gtm_ack_timer16 - acknowledge timer event (free-run timers only)
> > + * @tmr: pointer to the gtm_timer structure obtained from gtm_get_timer
> > + * @events: events mask to ack
> > + *
> > + * Thus function used to acknowledge timer interrupt event, use it inside the
> > + * interrupt handler.
> > + */
> > +static inline void gtm_ack_timer16(struct gtm_timer *tmr, u16 events)
> > +{
> > + out_be16(tmr->gtevr, events);
> > +}
>
> Drop 'inline' and expect gcc to do the right thing.
Not sure about newer gccs, but older complained about "defined but not
used" functions w/o inline keyword. I'm almost sure that this is still
true. I can surely use __maybe_unused, but "static inline" is pretty
settled tradition, plus this function is small enough anyway.
--
Anton Vorontsov
email: cbouatmailru at gmail.com
irc://irc.freenode.net/bd2
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