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authorLinus Torvalds <torvalds@linux-foundation.org>2018-04-02 20:20:12 -0700
committerLinus Torvalds <torvalds@linux-foundation.org>2018-04-02 20:20:12 -0700
commitf5a8eb632b562bd9c16c389f5db3a5260fba4157 (patch)
tree82687234d772ff8f72a31e598fe16553885c56c9 /drivers/clocksource
parentc9297d284126b80c9cfd72c690e0da531c99fc48 (diff)
parentdd3b8c329aa270027fba61a02a12600972dc3983 (diff)
Merge tag 'arch-removal' of git://git.kernel.org/pub/scm/linux/kernel/git/arnd/asm-generic
Pul removal of obsolete architecture ports from Arnd Bergmann: "This removes the entire architecture code for blackfin, cris, frv, m32r, metag, mn10300, score, and tile, including the associated device drivers. I have been working with the (former) maintainers for each one to ensure that my interpretation was right and the code is definitely unused in mainline kernels. Many had fond memories of working on the respective ports to start with and getting them included in upstream, but also saw no point in keeping the port alive without any users. In the end, it seems that while the eight architectures are extremely different, they all suffered the same fate: There was one company in charge of an SoC line, a CPU microarchitecture and a software ecosystem, which was more costly than licensing newer off-the-shelf CPU cores from a third party (typically ARM, MIPS, or RISC-V). It seems that all the SoC product lines are still around, but have not used the custom CPU architectures for several years at this point. In contrast, CPU instruction sets that remain popular and have actively maintained kernel ports tend to all be used across multiple licensees. [ See the new nds32 port merged in the previous commit for the next generation of "one company in charge of an SoC line, a CPU microarchitecture and a software ecosystem" - Linus ] The removal came out of a discussion that is now documented at https://lwn.net/Articles/748074/. Unlike the original plans, I'm not marking any ports as deprecated but remove them all at once after I made sure that they are all unused. Some architectures (notably tile, mn10300, and blackfin) are still being shipped in products with old kernels, but those products will never be updated to newer kernel releases. After this series, we still have a few architectures without mainline gcc support: - unicore32 and hexagon both have very outdated gcc releases, but the maintainers promised to work on providing something newer. At least in case of hexagon, this will only be llvm, not gcc. - openrisc, risc-v and nds32 are still in the process of finishing their support or getting it added to mainline gcc in the first place. They all have patched gcc-7.3 ports that work to some degree, but complete upstream support won't happen before gcc-8.1. Csky posted their first kernel patch set last week, their situation will be similar [ Palmer Dabbelt points out that RISC-V support is in mainline gcc since gcc-7, although gcc-7.3.0 is the recommended minimum - Linus ]" This really says it all: 2498 files changed, 95 insertions(+), 467668 deletions(-) * tag 'arch-removal' of git://git.kernel.org/pub/scm/linux/kernel/git/arnd/asm-generic: (74 commits) MAINTAINERS: UNICORE32: Change email account staging: iio: remove iio-trig-bfin-timer driver tty: hvc: remove tile driver tty: remove bfin_jtag_comm and hvc_bfin_jtag drivers serial: remove tile uart driver serial: remove m32r_sio driver serial: remove blackfin drivers serial: remove cris/etrax uart drivers usb: Remove Blackfin references in USB support usb: isp1362: remove blackfin arch glue usb: musb: remove blackfin port usb: host: remove tilegx platform glue pwm: remove pwm-bfin driver i2c: remove bfin-twi driver spi: remove blackfin related host drivers watchdog: remove bfin_wdt driver can: remove bfin_can driver mmc: remove bfin_sdh driver input: misc: remove blackfin rotary driver input: keyboard: remove bf54x driver ...
Diffstat (limited to 'drivers/clocksource')
-rw-r--r--drivers/clocksource/Kconfig5
-rw-r--r--drivers/clocksource/Makefile1
-rw-r--r--drivers/clocksource/metag_generic.c161
3 files changed, 0 insertions, 167 deletions
diff --git a/drivers/clocksource/Kconfig b/drivers/clocksource/Kconfig
index 14c9796e37ac..6021a5af21da 100644
--- a/drivers/clocksource/Kconfig
+++ b/drivers/clocksource/Kconfig
@@ -392,11 +392,6 @@ config ATMEL_ST
help
Support for the Atmel ST timer.
-config CLKSRC_METAG_GENERIC
- def_bool y if METAG
- help
- This option enables support for the Meta per-thread timers.
-
config CLKSRC_EXYNOS_MCT
bool "Exynos multi core timer driver" if COMPILE_TEST
depends on ARM || ARM64
diff --git a/drivers/clocksource/Makefile b/drivers/clocksource/Makefile
index a79523b22e52..f0cb07637a65 100644
--- a/drivers/clocksource/Makefile
+++ b/drivers/clocksource/Makefile
@@ -61,7 +61,6 @@ obj-$(CONFIG_ARM_ARCH_TIMER) += arm_arch_timer.o
obj-$(CONFIG_ARM_GLOBAL_TIMER) += arm_global_timer.o
obj-$(CONFIG_ARMV7M_SYSTICK) += armv7m_systick.o
obj-$(CONFIG_ARM_TIMER_SP804) += timer-sp804.o
-obj-$(CONFIG_CLKSRC_METAG_GENERIC) += metag_generic.o
obj-$(CONFIG_ARCH_HAS_TICK_BROADCAST) += dummy_timer.o
obj-$(CONFIG_KEYSTONE_TIMER) += timer-keystone.o
obj-$(CONFIG_INTEGRATOR_AP_TIMER) += timer-integrator-ap.o
diff --git a/drivers/clocksource/metag_generic.c b/drivers/clocksource/metag_generic.c
deleted file mode 100644
index 3e5fa2f62d5f..000000000000
--- a/drivers/clocksource/metag_generic.c
+++ /dev/null
@@ -1,161 +0,0 @@
-/*
- * Copyright (C) 2005-2013 Imagination Technologies Ltd.
- *
- * This program is free software; you can redistribute it and/or modify
- * it under the terms of the GNU General Public License version 2 as
- * published by the Free Software Foundation.
- *
- * 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, see <http://www.gnu.org/licenses/>.
- *
- *
- * Support for Meta per-thread timers.
- *
- * Meta hardware threads have 2 timers. The background timer (TXTIMER) is used
- * as a free-running time base (hz clocksource), and the interrupt timer
- * (TXTIMERI) is used for the timer interrupt (clock event). Both counters
- * traditionally count at approximately 1MHz.
- */
-
-#include <clocksource/metag_generic.h>
-#include <linux/cpu.h>
-#include <linux/errno.h>
-#include <linux/sched.h>
-#include <linux/kernel.h>
-#include <linux/param.h>
-#include <linux/time.h>
-#include <linux/init.h>
-#include <linux/proc_fs.h>
-#include <linux/clocksource.h>
-#include <linux/clockchips.h>
-#include <linux/interrupt.h>
-
-#include <asm/clock.h>
-#include <asm/hwthread.h>
-#include <asm/core_reg.h>
-#include <asm/metag_mem.h>
-#include <asm/tbx.h>
-
-#define HARDWARE_FREQ 1000000 /* 1MHz */
-#define HARDWARE_DIV 1 /* divide by 1 = 1MHz clock */
-#define HARDWARE_TO_NS_SHIFT 10 /* convert ticks to ns */
-
-static unsigned int hwtimer_freq = HARDWARE_FREQ;
-static DEFINE_PER_CPU(struct clock_event_device, local_clockevent);
-static DEFINE_PER_CPU(char [11], local_clockevent_name);
-
-static int metag_timer_set_next_event(unsigned long delta,
- struct clock_event_device *dev)
-{
- __core_reg_set(TXTIMERI, -delta);
- return 0;
-}
-
-static u64 metag_clocksource_read(struct clocksource *cs)
-{
- return __core_reg_get(TXTIMER);
-}
-
-static struct clocksource clocksource_metag = {
- .name = "META",
- .rating = 200,
- .mask = CLOCKSOURCE_MASK(32),
- .read = metag_clocksource_read,
- .flags = CLOCK_SOURCE_IS_CONTINUOUS,
-};
-
-static irqreturn_t metag_timer_interrupt(int irq, void *dummy)
-{
- struct clock_event_device *evt = this_cpu_ptr(&local_clockevent);
-
- evt->event_handler(evt);
-
- return IRQ_HANDLED;
-}
-
-static struct irqaction metag_timer_irq = {
- .name = "META core timer",
- .handler = metag_timer_interrupt,
- .flags = IRQF_TIMER | IRQF_IRQPOLL | IRQF_PERCPU,
-};
-
-unsigned long long sched_clock(void)
-{
- unsigned long long ticks = __core_reg_get(TXTIMER);
- return ticks << HARDWARE_TO_NS_SHIFT;
-}
-
-static int arch_timer_starting_cpu(unsigned int cpu)
-{
- unsigned int txdivtime;
- struct clock_event_device *clk = &per_cpu(local_clockevent, cpu);
- char *name = per_cpu(local_clockevent_name, cpu);
-
- txdivtime = __core_reg_get(TXDIVTIME);
-
- txdivtime &= ~TXDIVTIME_DIV_BITS;
- txdivtime |= (HARDWARE_DIV & TXDIVTIME_DIV_BITS);
-
- __core_reg_set(TXDIVTIME, txdivtime);
-
- sprintf(name, "META %d", cpu);
- clk->name = name;
- clk->features = CLOCK_EVT_FEAT_ONESHOT,
-
- clk->rating = 200,
- clk->shift = 12,
- clk->irq = tbisig_map(TBID_SIGNUM_TRT),
- clk->set_next_event = metag_timer_set_next_event,
-
- clk->mult = div_sc(hwtimer_freq, NSEC_PER_SEC, clk->shift);
- clk->max_delta_ns = clockevent_delta2ns(0x7fffffff, clk);
- clk->max_delta_ticks = 0x7fffffff;
- clk->min_delta_ns = clockevent_delta2ns(0xf, clk);
- clk->min_delta_ticks = 0xf;
- clk->cpumask = cpumask_of(cpu);
-
- clockevents_register_device(clk);
-
- /*
- * For all non-boot CPUs we need to synchronize our free
- * running clock (TXTIMER) with the boot CPU's clock.
- *
- * While this won't be accurate, it should be close enough.
- */
- if (cpu) {
- unsigned int thread0 = cpu_2_hwthread_id[0];
- unsigned long val;
-
- val = core_reg_read(TXUCT_ID, TXTIMER_REGNUM, thread0);
- __core_reg_set(TXTIMER, val);
- }
- return 0;
-}
-
-int __init metag_generic_timer_init(void)
-{
- /*
- * On Meta 2 SoCs, the actual frequency of the timer is based on the
- * Meta core clock speed divided by an integer, so it is only
- * approximately 1MHz. Calculating the real frequency here drastically
- * reduces clock skew on these SoCs.
- */
-#ifdef CONFIG_METAG_META21
- hwtimer_freq = get_coreclock() / (metag_in32(EXPAND_TIMER_DIV) + 1);
-#endif
- pr_info("Timer frequency: %u Hz\n", hwtimer_freq);
-
- clocksource_register_hz(&clocksource_metag, hwtimer_freq);
-
- setup_irq(tbisig_map(TBID_SIGNUM_TRT), &metag_timer_irq);
-
- /* Hook cpu boot to configure the CPU's timers */
- return cpuhp_setup_state(CPUHP_AP_METAG_TIMER_STARTING,
- "clockevents/metag:starting",
- arch_timer_starting_cpu, NULL);
-}