[PATCH RFC 07/20] clksource: timer-oxnas-rps: remove obsolete timer driver

From: Neil Armstrong
Date: Fri Mar 31 2023 - 04:35:37 EST


Due to lack of maintainance and stall of development for a few years now,
and since no new features will ever be added upstream, remove support
for OX810 and OX820 timer.

Signed-off-by: Neil Armstrong <neil.armstrong@xxxxxxxxxx>
---
drivers/clocksource/Kconfig | 7 -
drivers/clocksource/Makefile | 1 -
drivers/clocksource/timer-oxnas-rps.c | 288 ----------------------------------
3 files changed, 296 deletions(-)

diff --git a/drivers/clocksource/Kconfig b/drivers/clocksource/Kconfig
index 5fc8f0e7fb38..cd494646ebf4 100644
--- a/drivers/clocksource/Kconfig
+++ b/drivers/clocksource/Kconfig
@@ -461,13 +461,6 @@ config VF_PIT_TIMER
help
Support for Periodic Interrupt Timer on Freescale Vybrid Family SoCs.

-config OXNAS_RPS_TIMER
- bool "Oxford Semiconductor OXNAS RPS Timers driver" if COMPILE_TEST
- select TIMER_OF
- select CLKSRC_MMIO
- help
- This enables support for the Oxford Semiconductor OXNAS RPS timers.
-
config SYS_SUPPORTS_SH_CMT
bool

diff --git a/drivers/clocksource/Makefile b/drivers/clocksource/Makefile
index 64ab547de97b..a15608cb0ea3 100644
--- a/drivers/clocksource/Makefile
+++ b/drivers/clocksource/Makefile
@@ -53,7 +53,6 @@ obj-$(CONFIG_CLKSRC_QCOM) += timer-qcom.o
obj-$(CONFIG_MTK_TIMER) += timer-mediatek.o
obj-$(CONFIG_CLKSRC_PISTACHIO) += timer-pistachio.o
obj-$(CONFIG_CLKSRC_TI_32K) += timer-ti-32k.o
-obj-$(CONFIG_OXNAS_RPS_TIMER) += timer-oxnas-rps.o
obj-$(CONFIG_OWL_TIMER) += timer-owl.o
obj-$(CONFIG_MILBEAUT_TIMER) += timer-milbeaut.o
obj-$(CONFIG_SPRD_TIMER) += timer-sprd.o
diff --git a/drivers/clocksource/timer-oxnas-rps.c b/drivers/clocksource/timer-oxnas-rps.c
deleted file mode 100644
index d514b44e67dd..000000000000
--- a/drivers/clocksource/timer-oxnas-rps.c
+++ /dev/null
@@ -1,288 +0,0 @@
-// SPDX-License-Identifier: GPL-2.0-only
-/*
- * drivers/clocksource/timer-oxnas-rps.c
- *
- * Copyright (C) 2009 Oxford Semiconductor Ltd
- * Copyright (C) 2013 Ma Haijun <mahaijuns@xxxxxxxxx>
- * Copyright (C) 2016 Neil Armstrong <narmstrong@xxxxxxxxxxxx>
- */
-
-#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
-
-#include <linux/init.h>
-#include <linux/irq.h>
-#include <linux/io.h>
-#include <linux/clk.h>
-#include <linux/slab.h>
-#include <linux/interrupt.h>
-#include <linux/of_irq.h>
-#include <linux/of_address.h>
-#include <linux/clockchips.h>
-#include <linux/sched_clock.h>
-
-/* TIMER1 used as tick
- * TIMER2 used as clocksource
- */
-
-/* Registers definitions */
-
-#define TIMER_LOAD_REG 0x0
-#define TIMER_CURR_REG 0x4
-#define TIMER_CTRL_REG 0x8
-#define TIMER_CLRINT_REG 0xC
-
-#define TIMER_BITS 24
-
-#define TIMER_MAX_VAL (BIT(TIMER_BITS) - 1)
-
-#define TIMER_PERIODIC BIT(6)
-#define TIMER_ENABLE BIT(7)
-
-#define TIMER_DIV1 (0)
-#define TIMER_DIV16 (1 << 2)
-#define TIMER_DIV256 (2 << 2)
-
-#define TIMER1_REG_OFFSET 0
-#define TIMER2_REG_OFFSET 0x20
-
-/* Clockevent & Clocksource data */
-
-struct oxnas_rps_timer {
- struct clock_event_device clkevent;
- void __iomem *clksrc_base;
- void __iomem *clkevt_base;
- unsigned long timer_period;
- unsigned int timer_prescaler;
- struct clk *clk;
- int irq;
-};
-
-static irqreturn_t oxnas_rps_timer_irq(int irq, void *dev_id)
-{
- struct oxnas_rps_timer *rps = dev_id;
-
- writel_relaxed(0, rps->clkevt_base + TIMER_CLRINT_REG);
-
- rps->clkevent.event_handler(&rps->clkevent);
-
- return IRQ_HANDLED;
-}
-
-static void oxnas_rps_timer_config(struct oxnas_rps_timer *rps,
- unsigned long period,
- unsigned int periodic)
-{
- uint32_t cfg = rps->timer_prescaler;
-
- if (period)
- cfg |= TIMER_ENABLE;
-
- if (periodic)
- cfg |= TIMER_PERIODIC;
-
- writel_relaxed(period, rps->clkevt_base + TIMER_LOAD_REG);
- writel_relaxed(cfg, rps->clkevt_base + TIMER_CTRL_REG);
-}
-
-static int oxnas_rps_timer_shutdown(struct clock_event_device *evt)
-{
- struct oxnas_rps_timer *rps =
- container_of(evt, struct oxnas_rps_timer, clkevent);
-
- oxnas_rps_timer_config(rps, 0, 0);
-
- return 0;
-}
-
-static int oxnas_rps_timer_set_periodic(struct clock_event_device *evt)
-{
- struct oxnas_rps_timer *rps =
- container_of(evt, struct oxnas_rps_timer, clkevent);
-
- oxnas_rps_timer_config(rps, rps->timer_period, 1);
-
- return 0;
-}
-
-static int oxnas_rps_timer_set_oneshot(struct clock_event_device *evt)
-{
- struct oxnas_rps_timer *rps =
- container_of(evt, struct oxnas_rps_timer, clkevent);
-
- oxnas_rps_timer_config(rps, rps->timer_period, 0);
-
- return 0;
-}
-
-static int oxnas_rps_timer_next_event(unsigned long delta,
- struct clock_event_device *evt)
-{
- struct oxnas_rps_timer *rps =
- container_of(evt, struct oxnas_rps_timer, clkevent);
-
- oxnas_rps_timer_config(rps, delta, 0);
-
- return 0;
-}
-
-static int __init oxnas_rps_clockevent_init(struct oxnas_rps_timer *rps)
-{
- ulong clk_rate = clk_get_rate(rps->clk);
- ulong timer_rate;
-
- /* Start with prescaler 1 */
- rps->timer_prescaler = TIMER_DIV1;
- rps->timer_period = DIV_ROUND_UP(clk_rate, HZ);
- timer_rate = clk_rate;
-
- if (rps->timer_period > TIMER_MAX_VAL) {
- rps->timer_prescaler = TIMER_DIV16;
- timer_rate = clk_rate / 16;
- rps->timer_period = DIV_ROUND_UP(timer_rate, HZ);
- }
- if (rps->timer_period > TIMER_MAX_VAL) {
- rps->timer_prescaler = TIMER_DIV256;
- timer_rate = clk_rate / 256;
- rps->timer_period = DIV_ROUND_UP(timer_rate, HZ);
- }
-
- rps->clkevent.name = "oxnas-rps";
- rps->clkevent.features = CLOCK_EVT_FEAT_PERIODIC |
- CLOCK_EVT_FEAT_ONESHOT |
- CLOCK_EVT_FEAT_DYNIRQ;
- rps->clkevent.tick_resume = oxnas_rps_timer_shutdown;
- rps->clkevent.set_state_shutdown = oxnas_rps_timer_shutdown;
- rps->clkevent.set_state_periodic = oxnas_rps_timer_set_periodic;
- rps->clkevent.set_state_oneshot = oxnas_rps_timer_set_oneshot;
- rps->clkevent.set_next_event = oxnas_rps_timer_next_event;
- rps->clkevent.rating = 200;
- rps->clkevent.cpumask = cpu_possible_mask;
- rps->clkevent.irq = rps->irq;
- clockevents_config_and_register(&rps->clkevent,
- timer_rate,
- 1,
- TIMER_MAX_VAL);
-
- pr_info("Registered clock event rate %luHz prescaler %x period %lu\n",
- clk_rate,
- rps->timer_prescaler,
- rps->timer_period);
-
- return 0;
-}
-
-/* Clocksource */
-
-static void __iomem *timer_sched_base;
-
-static u64 notrace oxnas_rps_read_sched_clock(void)
-{
- return ~readl_relaxed(timer_sched_base);
-}
-
-static int __init oxnas_rps_clocksource_init(struct oxnas_rps_timer *rps)
-{
- ulong clk_rate = clk_get_rate(rps->clk);
- int ret;
-
- /* use prescale 16 */
- clk_rate = clk_rate / 16;
-
- writel_relaxed(TIMER_MAX_VAL, rps->clksrc_base + TIMER_LOAD_REG);
- writel_relaxed(TIMER_PERIODIC | TIMER_ENABLE | TIMER_DIV16,
- rps->clksrc_base + TIMER_CTRL_REG);
-
- timer_sched_base = rps->clksrc_base + TIMER_CURR_REG;
- sched_clock_register(oxnas_rps_read_sched_clock,
- TIMER_BITS, clk_rate);
- ret = clocksource_mmio_init(timer_sched_base,
- "oxnas_rps_clocksource_timer",
- clk_rate, 250, TIMER_BITS,
- clocksource_mmio_readl_down);
- if (WARN_ON(ret)) {
- pr_err("can't register clocksource\n");
- return ret;
- }
-
- pr_info("Registered clocksource rate %luHz\n", clk_rate);
-
- return 0;
-}
-
-static int __init oxnas_rps_timer_init(struct device_node *np)
-{
- struct oxnas_rps_timer *rps;
- void __iomem *base;
- int ret;
-
- rps = kzalloc(sizeof(*rps), GFP_KERNEL);
- if (!rps)
- return -ENOMEM;
-
- rps->clk = of_clk_get(np, 0);
- if (IS_ERR(rps->clk)) {
- ret = PTR_ERR(rps->clk);
- goto err_alloc;
- }
-
- ret = clk_prepare_enable(rps->clk);
- if (ret)
- goto err_clk;
-
- base = of_iomap(np, 0);
- if (!base) {
- ret = -ENXIO;
- goto err_clk_prepare;
- }
-
- rps->irq = irq_of_parse_and_map(np, 0);
- if (!rps->irq) {
- ret = -EINVAL;
- goto err_iomap;
- }
-
- rps->clkevt_base = base + TIMER1_REG_OFFSET;
- rps->clksrc_base = base + TIMER2_REG_OFFSET;
-
- /* Disable timers */
- writel_relaxed(0, rps->clkevt_base + TIMER_CTRL_REG);
- writel_relaxed(0, rps->clksrc_base + TIMER_CTRL_REG);
- writel_relaxed(0, rps->clkevt_base + TIMER_LOAD_REG);
- writel_relaxed(0, rps->clksrc_base + TIMER_LOAD_REG);
- writel_relaxed(0, rps->clkevt_base + TIMER_CLRINT_REG);
- writel_relaxed(0, rps->clksrc_base + TIMER_CLRINT_REG);
-
- ret = request_irq(rps->irq, oxnas_rps_timer_irq,
- IRQF_TIMER | IRQF_IRQPOLL,
- "rps-timer", rps);
- if (ret)
- goto err_iomap;
-
- ret = oxnas_rps_clocksource_init(rps);
- if (ret)
- goto err_irqreq;
-
- ret = oxnas_rps_clockevent_init(rps);
- if (ret)
- goto err_irqreq;
-
- return 0;
-
-err_irqreq:
- free_irq(rps->irq, rps);
-err_iomap:
- iounmap(base);
-err_clk_prepare:
- clk_disable_unprepare(rps->clk);
-err_clk:
- clk_put(rps->clk);
-err_alloc:
- kfree(rps);
-
- return ret;
-}
-
-TIMER_OF_DECLARE(ox810se_rps,
- "oxsemi,ox810se-rps-timer", oxnas_rps_timer_init);
-TIMER_OF_DECLARE(ox820_rps,
- "oxsemi,ox820-rps-timer", oxnas_rps_timer_init);

--
2.34.1