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authorLinus Torvalds <torvalds@linux-foundation.org>2012-10-01 18:24:44 -0700
committerLinus Torvalds <torvalds@linux-foundation.org>2012-10-01 18:24:44 -0700
commit11801e9de26992d37cb869cc74f389b6a7677e0e (patch)
tree322b7ea2b475d52da27d3e01f5bc2992bb708d59 /drivers
parent1a58ddfc0fcf3d83a92573c71771962f9b218993 (diff)
parentb6e3b5c2fea9c76617e101cbbc54ed14961f9dee (diff)
downloadlinux-linaro-stable-11801e9de26992d37cb869cc74f389b6a7677e0e.tar.gz
Merge tag 'soc' of git://git.kernel.org/pub/scm/linux/kernel/git/arm/arm-soc
Pull ARM soc-specific updates from Olof Johansson: "Most notable here is probably the addition of basic support for the BCM2835, an SoC used in some of the Roku 2 players as well as the much-hyped Raspberry Pi, cleaned up and contributed by Stephen Warren. It's still early days on mainline support, with just the basics working. But it has to start somewhere! Beyond that there's some conversions of clock infrastructure on tegra to common clock, misc updates for several other platforms, and OMAP now has its own bus (under drivers/bus) to manage its devices through. This branch adds two new directories outside of arch/arm: drivers/irqchip for new irq controllers, and drivers/bus for the above OMAP bus. It's expected that some of the other platforms will migrate parts of their platforms to those directories over time as well." Fix up trivial conflicts with the clk infrastructure changes. * tag 'soc' of git://git.kernel.org/pub/scm/linux/kernel/git/arm/arm-soc: (62 commits) ARM: shmobile: add new __iomem annotation for new code ARM: LPC32xx: Support GPI 28 ARM: LPC32xx: Platform update for devicetree completion of spi-pl022 ARM: LPC32xx: Board cleanup irqchip: fill in empty Kconfig ARM: SAMSUNG: Add check for NULL in clock interface ARM: EXYNOS: Put PCM, Slimbus, Spdif clocks to off state ARM: EXYNOS: Add bus clock for FIMD ARM: SAMSUNG: Fix HDMI related warnings ARM: S3C24XX: Add .get_rate callback for "camif-upll" clock ARM: EXYNOS: Fix incorrect help text ARM: EXYNOS: Turn off clocks for NAND, OneNAND and TSI controllers ARM: OMAP: AM33xx hwmod: fixup SPI after platform_data move MAINTAINERS: add an entry for the BCM2835 ARM sub-architecture ARM: bcm2835: instantiate console UART ARM: bcm2835: add stub clock driver ARM: bcm2835: add system timer ARM: bcm2835: add interrupt controller driver ARM: add infra-structure for BCM2835 and Raspberry Pi ARM: tegra20: add CPU hotplug support ...
Diffstat (limited to 'drivers')
-rw-r--r--drivers/Kconfig2
-rw-r--r--drivers/Makefile2
-rw-r--r--drivers/clk/Makefile1
-rw-r--r--drivers/clk/clk-bcm2835.c59
-rw-r--r--drivers/clocksource/Makefile2
-rw-r--r--drivers/clocksource/bcm2835_timer.c161
-rw-r--r--drivers/irqchip/Kconfig1
-rw-r--r--drivers/irqchip/Makefile1
-rw-r--r--drivers/irqchip/irq-bcm2835.c223
9 files changed, 452 insertions, 0 deletions
diff --git a/drivers/Kconfig b/drivers/Kconfig
index ece958d3762e..36d3daa19a74 100644
--- a/drivers/Kconfig
+++ b/drivers/Kconfig
@@ -152,4 +152,6 @@ source "drivers/vme/Kconfig"
source "drivers/pwm/Kconfig"
+source "drivers/irqchip/Kconfig"
+
endmenu
diff --git a/drivers/Makefile b/drivers/Makefile
index 5b421840c48d..8c30e73cd94c 100644
--- a/drivers/Makefile
+++ b/drivers/Makefile
@@ -5,6 +5,8 @@
# Rewritten to use lists instead of if-statements.
#
+obj-y += irqchip/
+
# GPIO must come after pinctrl as gpios may need to mux pins etc
obj-y += pinctrl/
obj-y += gpio/
diff --git a/drivers/clk/Makefile b/drivers/clk/Makefile
index b7b862077d88..2b861625bdae 100644
--- a/drivers/clk/Makefile
+++ b/drivers/clk/Makefile
@@ -4,6 +4,7 @@ obj-$(CONFIG_CLKDEV_LOOKUP) += clkdev.o
obj-$(CONFIG_COMMON_CLK) += clk.o clk-fixed-rate.o clk-gate.o \
clk-mux.o clk-divider.o clk-fixed-factor.o
# SoCs specific
+obj-$(CONFIG_ARCH_BCM2835) += clk-bcm2835.o
obj-$(CONFIG_ARCH_NOMADIK) += clk-nomadik.o
obj-$(CONFIG_ARCH_HIGHBANK) += clk-highbank.o
obj-$(CONFIG_ARCH_MXS) += mxs/
diff --git a/drivers/clk/clk-bcm2835.c b/drivers/clk/clk-bcm2835.c
new file mode 100644
index 000000000000..67ad16b20b81
--- /dev/null
+++ b/drivers/clk/clk-bcm2835.c
@@ -0,0 +1,59 @@
+/*
+ * Copyright (C) 2010 Broadcom
+ * Copyright (C) 2012 Stephen Warren
+ *
+ * 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.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
+ */
+
+#include <linux/clk-provider.h>
+#include <linux/clkdev.h>
+#include <linux/clk/bcm2835.h>
+
+/*
+ * These are fixed clocks. They're probably not all root clocks and it may
+ * be possible to turn them on and off but until this is mapped out better
+ * it's the only way they can be used.
+ */
+void __init bcm2835_init_clocks(void)
+{
+ struct clk *clk;
+ int ret;
+
+ clk = clk_register_fixed_rate(NULL, "sys_pclk", NULL, CLK_IS_ROOT,
+ 250000000);
+ if (!clk)
+ pr_err("sys_pclk not registered\n");
+
+ clk = clk_register_fixed_rate(NULL, "apb_pclk", NULL, CLK_IS_ROOT,
+ 126000000);
+ if (!clk)
+ pr_err("apb_pclk not registered\n");
+
+ clk = clk_register_fixed_rate(NULL, "uart0_pclk", NULL, CLK_IS_ROOT,
+ 3000000);
+ if (!clk)
+ pr_err("uart0_pclk not registered\n");
+ ret = clk_register_clkdev(clk, NULL, "20201000.uart");
+ if (ret)
+ pr_err("uart0_pclk alias not registered\n");
+
+ clk = clk_register_fixed_rate(NULL, "uart1_pclk", NULL, CLK_IS_ROOT,
+ 125000000);
+ if (!clk)
+ pr_err("uart1_pclk not registered\n");
+ ret = clk_register_clkdev(clk, NULL, "20215000.uart");
+ if (ret)
+ pr_err("uart0_pclk alias not registered\n");
+}
diff --git a/drivers/clocksource/Makefile b/drivers/clocksource/Makefile
index 65919901a301..603be366f762 100644
--- a/drivers/clocksource/Makefile
+++ b/drivers/clocksource/Makefile
@@ -13,4 +13,6 @@ obj-$(CONFIG_DW_APB_TIMER) += dw_apb_timer.o
obj-$(CONFIG_DW_APB_TIMER_OF) += dw_apb_timer_of.o
obj-$(CONFIG_CLKSRC_DBX500_PRCMU) += clksrc-dbx500-prcmu.o
obj-$(CONFIG_ARMADA_370_XP_TIMER) += time-armada-370-xp.o
+obj-$(CONFIG_ARCH_BCM2835) += bcm2835_timer.o
+
obj-$(CONFIG_CLKSRC_ARM_GENERIC) += arm_generic.o
diff --git a/drivers/clocksource/bcm2835_timer.c b/drivers/clocksource/bcm2835_timer.c
new file mode 100644
index 000000000000..bc19f12c20ce
--- /dev/null
+++ b/drivers/clocksource/bcm2835_timer.c
@@ -0,0 +1,161 @@
+/*
+ * Copyright 2012 Simon Arlott
+ *
+ * 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.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
+ */
+
+#include <linux/bcm2835_timer.h>
+#include <linux/bitops.h>
+#include <linux/clockchips.h>
+#include <linux/clocksource.h>
+#include <linux/interrupt.h>
+#include <linux/irqreturn.h>
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/of_address.h>
+#include <linux/of_irq.h>
+#include <linux/of_platform.h>
+#include <linux/slab.h>
+#include <linux/string.h>
+
+#include <asm/sched_clock.h>
+#include <asm/irq.h>
+
+#define REG_CONTROL 0x00
+#define REG_COUNTER_LO 0x04
+#define REG_COUNTER_HI 0x08
+#define REG_COMPARE(n) (0x0c + (n) * 4)
+#define MAX_TIMER 3
+#define DEFAULT_TIMER 3
+
+struct bcm2835_timer {
+ void __iomem *control;
+ void __iomem *compare;
+ int match_mask;
+ struct clock_event_device evt;
+ struct irqaction act;
+};
+
+static void __iomem *system_clock __read_mostly;
+
+static u32 notrace bcm2835_sched_read(void)
+{
+ return readl_relaxed(system_clock);
+}
+
+static void bcm2835_time_set_mode(enum clock_event_mode mode,
+ struct clock_event_device *evt_dev)
+{
+ switch (mode) {
+ case CLOCK_EVT_MODE_ONESHOT:
+ case CLOCK_EVT_MODE_UNUSED:
+ case CLOCK_EVT_MODE_SHUTDOWN:
+ case CLOCK_EVT_MODE_RESUME:
+ break;
+ default:
+ WARN(1, "%s: unhandled event mode %d\n", __func__, mode);
+ break;
+ }
+}
+
+static int bcm2835_time_set_next_event(unsigned long event,
+ struct clock_event_device *evt_dev)
+{
+ struct bcm2835_timer *timer = container_of(evt_dev,
+ struct bcm2835_timer, evt);
+ writel_relaxed(readl_relaxed(system_clock) + event,
+ timer->compare);
+ return 0;
+}
+
+static irqreturn_t bcm2835_time_interrupt(int irq, void *dev_id)
+{
+ struct bcm2835_timer *timer = dev_id;
+ void (*event_handler)(struct clock_event_device *);
+ if (readl_relaxed(timer->control) & timer->match_mask) {
+ writel_relaxed(timer->match_mask, timer->control);
+
+ event_handler = ACCESS_ONCE(timer->evt.event_handler);
+ if (event_handler)
+ event_handler(&timer->evt);
+ return IRQ_HANDLED;
+ } else {
+ return IRQ_NONE;
+ }
+}
+
+static struct of_device_id bcm2835_time_match[] __initconst = {
+ { .compatible = "brcm,bcm2835-system-timer" },
+ {}
+};
+
+static void __init bcm2835_time_init(void)
+{
+ struct device_node *node;
+ void __iomem *base;
+ u32 freq;
+ int irq;
+ struct bcm2835_timer *timer;
+
+ node = of_find_matching_node(NULL, bcm2835_time_match);
+ if (!node)
+ panic("No bcm2835 timer node");
+
+ base = of_iomap(node, 0);
+ if (!base)
+ panic("Can't remap registers");
+
+ if (of_property_read_u32(node, "clock-frequency", &freq))
+ panic("Can't read clock-frequency");
+
+ system_clock = base + REG_COUNTER_LO;
+ setup_sched_clock(bcm2835_sched_read, 32, freq);
+
+ clocksource_mmio_init(base + REG_COUNTER_LO, node->name,
+ freq, 300, 32, clocksource_mmio_readl_up);
+
+ irq = irq_of_parse_and_map(node, DEFAULT_TIMER);
+ if (irq <= 0)
+ panic("Can't parse IRQ");
+
+ timer = kzalloc(sizeof(*timer), GFP_KERNEL);
+ if (!timer)
+ panic("Can't allocate timer struct\n");
+
+ timer->control = base + REG_CONTROL;
+ timer->compare = base + REG_COMPARE(DEFAULT_TIMER);
+ timer->match_mask = BIT(DEFAULT_TIMER);
+ timer->evt.name = node->name;
+ timer->evt.rating = 300;
+ timer->evt.features = CLOCK_EVT_FEAT_ONESHOT;
+ timer->evt.set_mode = bcm2835_time_set_mode;
+ timer->evt.set_next_event = bcm2835_time_set_next_event;
+ timer->evt.cpumask = cpumask_of(0);
+ timer->act.name = node->name;
+ timer->act.flags = IRQF_TIMER | IRQF_SHARED;
+ timer->act.dev_id = timer;
+ timer->act.handler = bcm2835_time_interrupt;
+
+ if (setup_irq(irq, &timer->act))
+ panic("Can't set up timer IRQ\n");
+
+ clockevents_config_and_register(&timer->evt, freq, 0xf, 0xffffffff);
+
+ pr_info("bcm2835: system timer (irq = %d)\n", irq);
+}
+
+struct sys_timer bcm2835_timer = {
+ .init = bcm2835_time_init,
+};
diff --git a/drivers/irqchip/Kconfig b/drivers/irqchip/Kconfig
new file mode 100644
index 000000000000..1bb8bf6d7fd4
--- /dev/null
+++ b/drivers/irqchip/Kconfig
@@ -0,0 +1 @@
+# empty
diff --git a/drivers/irqchip/Makefile b/drivers/irqchip/Makefile
new file mode 100644
index 000000000000..054321db4350
--- /dev/null
+++ b/drivers/irqchip/Makefile
@@ -0,0 +1 @@
+obj-$(CONFIG_ARCH_BCM2835) += irq-bcm2835.o
diff --git a/drivers/irqchip/irq-bcm2835.c b/drivers/irqchip/irq-bcm2835.c
new file mode 100644
index 000000000000..dc670ccc6978
--- /dev/null
+++ b/drivers/irqchip/irq-bcm2835.c
@@ -0,0 +1,223 @@
+/*
+ * Copyright 2010 Broadcom
+ * Copyright 2012 Simon Arlott, Chris Boot, Stephen Warren
+ *
+ * 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.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * Quirk 1: Shortcut interrupts don't set the bank 1/2 register pending bits
+ *
+ * If an interrupt fires on bank 1 that isn't in the shortcuts list, bit 8
+ * on bank 0 is set to signify that an interrupt in bank 1 has fired, and
+ * to look in the bank 1 status register for more information.
+ *
+ * If an interrupt fires on bank 1 that _is_ in the shortcuts list, its
+ * shortcut bit in bank 0 is set as well as its interrupt bit in the bank 1
+ * status register, but bank 0 bit 8 is _not_ set.
+ *
+ * Quirk 2: You can't mask the register 1/2 pending interrupts
+ *
+ * In a proper cascaded interrupt controller, the interrupt lines with
+ * cascaded interrupt controllers on them are just normal interrupt lines.
+ * You can mask the interrupts and get on with things. With this controller
+ * you can't do that.
+ *
+ * Quirk 3: The shortcut interrupts can't be (un)masked in bank 0
+ *
+ * Those interrupts that have shortcuts can only be masked/unmasked in
+ * their respective banks' enable/disable registers. Doing so in the bank 0
+ * enable/disable registers has no effect.
+ *
+ * The FIQ control register:
+ * Bits 0-6: IRQ (index in order of interrupts from banks 1, 2, then 0)
+ * Bit 7: Enable FIQ generation
+ * Bits 8+: Unused
+ *
+ * An interrupt must be disabled before configuring it for FIQ generation
+ * otherwise both handlers will fire at the same time!
+ */
+
+#include <linux/io.h>
+#include <linux/slab.h>
+#include <linux/of_address.h>
+#include <linux/of_irq.h>
+#include <linux/irqdomain.h>
+#include <linux/irqchip/bcm2835.h>
+
+#include <asm/exception.h>
+
+/* Put the bank and irq (32 bits) into the hwirq */
+#define MAKE_HWIRQ(b, n) ((b << 5) | (n))
+#define HWIRQ_BANK(i) (i >> 5)
+#define HWIRQ_BIT(i) BIT(i & 0x1f)
+
+#define NR_IRQS_BANK0 8
+#define BANK0_HWIRQ_MASK 0xff
+/* Shortcuts can't be disabled so any unknown new ones need to be masked */
+#define SHORTCUT1_MASK 0x00007c00
+#define SHORTCUT2_MASK 0x001f8000
+#define SHORTCUT_SHIFT 10
+#define BANK1_HWIRQ BIT(8)
+#define BANK2_HWIRQ BIT(9)
+#define BANK0_VALID_MASK (BANK0_HWIRQ_MASK | BANK1_HWIRQ | BANK2_HWIRQ \
+ | SHORTCUT1_MASK | SHORTCUT2_MASK)
+
+#define REG_FIQ_CONTROL 0x0c
+
+#define NR_BANKS 3
+#define IRQS_PER_BANK 32
+
+static int reg_pending[] __initconst = { 0x00, 0x04, 0x08 };
+static int reg_enable[] __initconst = { 0x18, 0x10, 0x14 };
+static int reg_disable[] __initconst = { 0x24, 0x1c, 0x20 };
+static int bank_irqs[] __initconst = { 8, 32, 32 };
+
+static const int shortcuts[] = {
+ 7, 9, 10, 18, 19, /* Bank 1 */
+ 21, 22, 23, 24, 25, 30 /* Bank 2 */
+};
+
+struct armctrl_ic {
+ void __iomem *base;
+ void __iomem *pending[NR_BANKS];
+ void __iomem *enable[NR_BANKS];
+ void __iomem *disable[NR_BANKS];
+ struct irq_domain *domain;
+};
+
+static struct armctrl_ic intc __read_mostly;
+
+static void armctrl_mask_irq(struct irq_data *d)
+{
+ writel_relaxed(HWIRQ_BIT(d->hwirq), intc.disable[HWIRQ_BANK(d->hwirq)]);
+}
+
+static void armctrl_unmask_irq(struct irq_data *d)
+{
+ writel_relaxed(HWIRQ_BIT(d->hwirq), intc.enable[HWIRQ_BANK(d->hwirq)]);
+}
+
+static struct irq_chip armctrl_chip = {
+ .name = "ARMCTRL-level",
+ .irq_mask = armctrl_mask_irq,
+ .irq_unmask = armctrl_unmask_irq
+};
+
+static int armctrl_xlate(struct irq_domain *d, struct device_node *ctrlr,
+ const u32 *intspec, unsigned int intsize,
+ unsigned long *out_hwirq, unsigned int *out_type)
+{
+ if (WARN_ON(intsize != 2))
+ return -EINVAL;
+
+ if (WARN_ON(intspec[0] >= NR_BANKS))
+ return -EINVAL;
+
+ if (WARN_ON(intspec[1] >= IRQS_PER_BANK))
+ return -EINVAL;
+
+ if (WARN_ON(intspec[0] == 0 && intspec[1] >= NR_IRQS_BANK0))
+ return -EINVAL;
+
+ *out_hwirq = MAKE_HWIRQ(intspec[0], intspec[1]);
+ *out_type = IRQ_TYPE_NONE;
+ return 0;
+}
+
+static struct irq_domain_ops armctrl_ops = {
+ .xlate = armctrl_xlate
+};
+
+static int __init armctrl_of_init(struct device_node *node,
+ struct device_node *parent)
+{
+ void __iomem *base;
+ int irq, b, i;
+
+ base = of_iomap(node, 0);
+ if (!base)
+ panic("%s: unable to map IC registers\n",
+ node->full_name);
+
+ intc.domain = irq_domain_add_linear(node, MAKE_HWIRQ(NR_BANKS, 0),
+ &armctrl_ops, NULL);
+ if (!intc.domain)
+ panic("%s: unable to create IRQ domain\n", node->full_name);
+
+ for (b = 0; b < NR_BANKS; b++) {
+ intc.pending[b] = base + reg_pending[b];
+ intc.enable[b] = base + reg_enable[b];
+ intc.disable[b] = base + reg_disable[b];
+
+ for (i = 0; i < bank_irqs[b]; i++) {
+ irq = irq_create_mapping(intc.domain, MAKE_HWIRQ(b, i));
+ BUG_ON(irq <= 0);
+ irq_set_chip_and_handler(irq, &armctrl_chip,
+ handle_level_irq);
+ set_irq_flags(irq, IRQF_VALID | IRQF_PROBE);
+ }
+ }
+ return 0;
+}
+
+static struct of_device_id irq_of_match[] __initconst = {
+ { .compatible = "brcm,bcm2835-armctrl-ic", .data = armctrl_of_init }
+};
+
+void __init bcm2835_init_irq(void)
+{
+ of_irq_init(irq_of_match);
+}
+
+/*
+ * Handle each interrupt across the entire interrupt controller. This reads the
+ * status register before handling each interrupt, which is necessary given that
+ * handle_IRQ may briefly re-enable interrupts for soft IRQ handling.
+ */
+
+static void armctrl_handle_bank(int bank, struct pt_regs *regs)
+{
+ u32 stat, irq;
+
+ while ((stat = readl_relaxed(intc.pending[bank]))) {
+ irq = MAKE_HWIRQ(bank, ffs(stat) - 1);
+ handle_IRQ(irq_linear_revmap(intc.domain, irq), regs);
+ }
+}
+
+static void armctrl_handle_shortcut(int bank, struct pt_regs *regs,
+ u32 stat)
+{
+ u32 irq = MAKE_HWIRQ(bank, shortcuts[ffs(stat >> SHORTCUT_SHIFT) - 1]);
+ handle_IRQ(irq_linear_revmap(intc.domain, irq), regs);
+}
+
+asmlinkage void __exception_irq_entry bcm2835_handle_irq(
+ struct pt_regs *regs)
+{
+ u32 stat, irq;
+
+ while ((stat = readl_relaxed(intc.pending[0]) & BANK0_VALID_MASK)) {
+ if (stat & BANK0_HWIRQ_MASK) {
+ irq = MAKE_HWIRQ(0, ffs(stat & BANK0_HWIRQ_MASK) - 1);
+ handle_IRQ(irq_linear_revmap(intc.domain, irq), regs);
+ } else if (stat & SHORTCUT1_MASK) {
+ armctrl_handle_shortcut(1, regs, stat & SHORTCUT1_MASK);
+ } else if (stat & SHORTCUT2_MASK) {
+ armctrl_handle_shortcut(2, regs, stat & SHORTCUT2_MASK);
+ } else if (stat & BANK1_HWIRQ) {
+ armctrl_handle_bank(1, regs);
+ } else if (stat & BANK2_HWIRQ) {
+ armctrl_handle_bank(2, regs);
+ } else {
+ BUG();
+ }
+ }
+}