[PATCH 6/8] [POWERPC] sysdev,qe_lib: implement FSL GTM support
Anton Vorontsov
avorontsov at ru.mvista.com
Wed Mar 12 04:24:29 EST 2008
GTM stands for General-purpose Timers Module and able to generate
timer{1,2,3,4} interrupts.
There are several limitations in this support:
1. Cascaded (32 bit) timers unimplemented (1-2, 3-4).
This is straightforward to implement when needed, two timers should
be marked as "requested" and configured as appropriate.
2. Super-cascaded (64 bit) timers unimplemented (1-2-3-4).
This is also straightforward to implement when needed, all timers
should be marked as "requested" and configured as appropriate.
Signed-off-by: Anton Vorontsov <avorontsov at ru.mvista.com>
---
Documentation/powerpc/booting-without-of.txt | 27 +++-
arch/powerpc/Kconfig | 5 +
arch/powerpc/sysdev/Makefile | 1 +
arch/powerpc/sysdev/fsl_gtm.c | 263 ++++++++++++++++++++++++++
arch/powerpc/sysdev/qe_lib/Kconfig | 5 +
arch/powerpc/sysdev/qe_lib/Makefile | 1 +
arch/powerpc/sysdev/qe_lib/gtm.c | 47 +++++
include/asm-powerpc/fsl_gtm.h | 138 ++++++++++++++
8 files changed, 486 insertions(+), 1 deletions(-)
create mode 100644 arch/powerpc/sysdev/fsl_gtm.c
create mode 100644 arch/powerpc/sysdev/qe_lib/gtm.c
create mode 100644 include/asm-powerpc/fsl_gtm.h
diff --git a/Documentation/powerpc/booting-without-of.txt b/Documentation/powerpc/booting-without-of.txt
index 8ae57f2..b506245 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 - Specifying interrupt information for devices
1) interrupts property
@@ -2811,6 +2812,30 @@ 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).
+ - reg : should contain gtm registers location and length (0x40).
+ - interrupts : should contain four interrupts.
+ - interrupt-parent : interrupt source phandle.
+
+ Example:
+
+ gtm at 500 {
+ compatible = "fsl,gtm";
+ reg = <0x500 0x40>;
+ interrupts = <90 8 78 8 84 8 72 8>;
+ interrupt-parent = <&ipic>;
+ };
+
+ gtm at 440 {
+ compatible = "fsl,qe-gtm", "fsl,gtm";
+ reg = <0x440 0x40>;
+ interrupts = <12 13 14 15>;
+ interrupt-parent = <&qeic>;
+ };
More devices will be defined as this spec matures.
diff --git a/arch/powerpc/Kconfig b/arch/powerpc/Kconfig
index 9c68592..0b27cbd 100644
--- a/arch/powerpc/Kconfig
+++ b/arch/powerpc/Kconfig
@@ -496,6 +496,11 @@ 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 62b6ef0..a7e8da4 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..975fe4e
--- /dev/null
+++ b/arch/powerpc/sysdev/fsl_gtm.c
@@ -0,0 +1,263 @@
+/*
+ * 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 <asm/fsl_gtm.h>
+
+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);
+
+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);
+
+int gtm_reset_ref_timer_16(struct gtm_timer *tmr, unsigned int hz, u16 ref,
+ bool ffr)
+{
+ struct gtm *gtm = tmr->gtm;
+ int num = tmr - >m->timers[0];
+ unsigned long flags;
+ unsigned int prescaler;
+ u8 iclk = GTMDR_ICLK_ICLK;
+ u8 psr;
+ u8 sps;
+
+ prescaler = gtm->clock / hz;
+
+ /*
+ * 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).
+ */
+ if (prescaler > 256 * 256 * 16)
+ return -EINVAL;
+
+ if (prescaler > 256 * 256) {
+ iclk = GTMDR_ICLK_SLGO;
+ prescaler /= 16;
+ }
+
+ if (prescaler > 256) {
+ psr = 256 - 1;
+ sps = prescaler / 256 - 1;
+ } else {
+ psr = prescaler - 1;
+ sps = 1 - 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));
+
+ out_be16(tmr->gtpsr, psr);
+ clrsetbits_be16(tmr->gtmdr, 0xFFFF, iclk | GTMDR_SPS(sps) |
+ GTMDR_ORI | (ffr ? GTMDR_FFR : 0));
+ out_be16(tmr->gtcnr, 0);
+ out_be16(tmr->gtrfr, ref);
+ out_be16(tmr->gtevr, 0xFFFF);
+
+ /* Let it be. */
+ clrbits8(tmr->gtcfr, GTCFR_STP(num));
+
+ spin_unlock_irqrestore(>m->lock, flags);
+
+ return 0;
+}
+EXPORT_SYMBOL(gtm_reset_ref_timer_16);
+
+void gtm_stop_timer_16(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));
+
+ spin_unlock_irqrestore(>m->lock, flags);
+}
+EXPORT_SYMBOL(gtm_stop_timer_16);
+
+static void __init gtm_set_shortcuts(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].gtpsr = ®s->gtpsr1;
+ 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].gtpsr = ®s->gtpsr2;
+ 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].gtpsr = ®s->gtpsr3;
+ 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].gtpsr = ®s->gtpsr4;
+ timers[3].gtcnr = ®s->gtcnr4;
+ timers[3].gtrfr = ®s->gtrfr4;
+ timers[3].gtevr = ®s->gtevr4;
+}
+
+static int __init gtm_get_clock(struct gtm *gtm, struct device_node *np)
+{
+ struct device_node *parent;
+ const u32 *clock;
+ int size;
+ int ret;
+
+ parent = of_get_parent(np);
+ if (!parent) {
+ pr_err("%s: no parent?\n", np->full_name);
+ return -EINVAL;
+ }
+
+ clock = of_get_property(parent, "clock-frequency", &size);
+ if (!clock || size != sizeof(*clock)) {
+ pr_err("%s: no clock-frequency for %s\n",
+ np->full_name, parent->full_name);
+ ret = -EINVAL;
+ goto err;
+ }
+
+ ret = 0;
+ gtm->clock = *clock;
+err:
+ of_node_put(parent);
+ return ret;
+}
+
+static int __init gtm_init_gtm(void)
+{
+ struct device_node *np;
+
+ for_each_compatible_node(np, NULL, "fsl,gtm") {
+ int i;
+ struct gtm *gtm;
+
+ 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);
+
+ if (gtm_get_clock(gtm, np))
+ goto err;
+
+ 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(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_gtm);
diff --git a/arch/powerpc/sysdev/qe_lib/Kconfig b/arch/powerpc/sysdev/qe_lib/Kconfig
index adc6621..c1f2849 100644
--- a/arch/powerpc/sysdev/qe_lib/Kconfig
+++ b/arch/powerpc/sysdev/qe_lib/Kconfig
@@ -20,3 +20,8 @@ config UCC
bool
default y if UCC_FAST || UCC_SLOW
+config QE_GTM
+ bool
+ default y if FSL_GTM
+ help
+ QE General-purpose Timers Module support
diff --git a/arch/powerpc/sysdev/qe_lib/Makefile b/arch/powerpc/sysdev/qe_lib/Makefile
index 874fe1a..3297a52 100644
--- a/arch/powerpc/sysdev/qe_lib/Makefile
+++ b/arch/powerpc/sysdev/qe_lib/Makefile
@@ -6,3 +6,4 @@ obj-$(CONFIG_QUICC_ENGINE)+= qe.o qe_ic.o qe_io.o
obj-$(CONFIG_UCC) += ucc.o
obj-$(CONFIG_UCC_SLOW) += ucc_slow.o
obj-$(CONFIG_UCC_FAST) += ucc_fast.o
+obj-$(CONFIG_QE_GTM) += gtm.o
diff --git a/arch/powerpc/sysdev/qe_lib/gtm.c b/arch/powerpc/sysdev/qe_lib/gtm.c
new file mode 100644
index 0000000..2ce9c25
--- /dev/null
+++ b/arch/powerpc/sysdev/qe_lib/gtm.c
@@ -0,0 +1,47 @@
+/*
+ * QE 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/of.h>
+#include <asm/qe.h>
+#include <asm/fsl_gtm.h>
+
+/*
+ * For now we just fixing up the clock -- it's brg-frequency for QE
+ * chips, generic code does not and should not know these details.
+ *
+ * Later we might want to set up BRGs, when QE will actually use
+ * them (there are TIMERCS bits in the CMXGCR register, but today
+ * these bits seem to be no-ops.
+ */
+static int __init qe_init_gtm(void)
+{
+ struct device_node *np;
+
+ for_each_compatible_node(np, NULL, "fsl,qe-gtm") {
+ struct gtm *gtm = np->data;
+
+ if (!gtm) {
+ /* fsl,qe-gtm without fsl,gtm compatible? */
+ WARN_ON(1);
+ continue;
+ }
+
+ gtm->clock = qe_get_brg_clk();
+ }
+
+ return 0;
+}
+arch_initcall(qe_init_gtm);
diff --git a/include/asm-powerpc/fsl_gtm.h b/include/asm-powerpc/fsl_gtm.h
new file mode 100644
index 0000000..bdb9d5a
--- /dev/null
+++ b/include/asm-powerpc/fsl_gtm.h
@@ -0,0 +1,138 @@
+/*
+ * 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>
+
+#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_FFR (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;
+};
+
+/**
+ * gtm_get_timer - request GTM timer for use 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.
+ */
+extern struct gtm_timer *gtm_get_timer(int width);
+
+/**
+ * gtm_put_timer - release GTM timer
+ * @width: timer width (only 16 bits wide timers implemented so far)
+ *
+ * This function releases GTM timer sp others might request it.
+ */
+extern void gtm_put_timer(struct gtm_timer *tmr);
+
+/**
+ * gtm_reset_ref_timer_16 - (re)set single (16 bits) timer in reference mode
+ * @tmr: pointer to the gtm_timer structure obtained from gtm_get_timer
+ * @hz: timer rate in Hz
+ * @ref: refernce value
+ * @ffr: free run flag
+ *
+ * Thus function (re)sets GTM timer so it counts up to the reference value and
+ * fires the interrupt when the value is reached. If ffr flag is set, timer
+ * will also reset itself upon reference value, otherwise it continues to
+ * increment.
+ */
+extern int gtm_reset_ref_timer_16(struct gtm_timer *tmr, unsigned int hz,
+ u16 ref, bool ffr);
+
+/**
+ * gtm_ack_ref_timer_16 - acknowledge timer event (free-run timers only)
+ * @tmr: pointer to the gtm_timer structure obtained from gtm_get_timer
+ *
+ * Thus function used to acknowledge timer interrupt event, use it inside the
+ * interrupt handler.
+ */
+static inline void gtm_ack_ref_timer_16(struct gtm_timer *tmr)
+{
+ out_be16(tmr->gtevr, 0xFFFF);
+}
+
+/**
+ * gtm_stop_timer_16 - stop single timer
+ * @tmr: pointer to the gtm_timer structure obtained from gtm_get_timer
+ *
+ * This function simply stops the GTM timer.
+ */
+extern void gtm_stop_timer_16(struct gtm_timer *tmr);
+
+#endif /* __ASM_FSL_GTM_H */
--
1.5.2.2
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