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ramips: mt76x8: disable unused Ralink systick driver

Browse Source 
The mt76x8 series SoCs use the MIPS generic systick timer. Sync the
upstream Ralink systick driver changes and disable it for mt76x8
target to reduce the kernel size.

Signed-off-by: Shiji Yang <yangshiji66@qq.com>
Link: https://github.com/openwrt/openwrt/pull/16844
Signed-off-by: Hauke Mehrtens <hauke@hauke-m.de>
(cherry picked from commit 0c57510ced)
Link: https://github.com/openwrt/openwrt/pull/17097
Signed-off-by: Petr Štetiar <ynezz@true.cz>
This commit is contained in:
Shiji Yang 2024-11-03 12:30:21 +08:00 committed by Petr Štetiar
parent 67269ae51e
commit 0a0950614b
No known key found for this signature in database
GPG Key ID: 58EE120F30CC02D3
7 changed files with 426 additions and 43 deletions
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2
target/linux/ramips/mt7620/config-6.6
View File

@ -8,7 +8,6 @@ CONFIG_ARCH_SUSPEND_POSSIBLE=y
CONFIG_BLK_MQ_PCI=y
CONFIG_CEVT_R4K=y
CONFIG_CEVT_SYSTICK_QUIRK=y
CONFIG_CLKEVT_RT3352=y
CONFIG_CLKSRC_MMIO=y
CONFIG_CLK_MTMIPS=y
CONFIG_CLONE_BACKWARDS=y
@ -180,6 +179,7 @@ CONFIG_PINCTRL_MTK_MTMIPS=y
CONFIG_PREEMPT_NONE_BUILD=y
CONFIG_PTP_1588_CLOCK_OPTIONAL=y
CONFIG_RALINK=y
CONFIG_RALINK_TIMER=y
CONFIG_RALINK_WDT=y
CONFIG_RANDSTRUCT_NONE=y
CONFIG_RATIONAL=y

6
target/linux/ramips/mt76x8/config-6.6
View File

@ -6,9 +6,6 @@ CONFIG_ARCH_MMAP_RND_COMPAT_BITS_MAX=15
CONFIG_ARCH_SUSPEND_POSSIBLE=y
CONFIG_BLK_MQ_PCI=y
CONFIG_CEVT_R4K=y
CONFIG_CEVT_SYSTICK_QUIRK=y
CONFIG_CLKEVT_RT3352=y
CONFIG_CLKSRC_MMIO=y
CONFIG_CLK_MTMIPS=y
CONFIG_CLONE_BACKWARDS=y
CONFIG_CMDLINE="rootfstype=squashfs,jffs2"
@ -173,6 +170,7 @@ CONFIG_PINCTRL_MTK_MTMIPS=y
CONFIG_PREEMPT_NONE_BUILD=y
CONFIG_PTP_1588_CLOCK_OPTIONAL=y
CONFIG_RALINK=y
# CONFIG_RALINK_TIMER is not set
# CONFIG_RALINK_WDT is not set
CONFIG_RANDSTRUCT_NONE=y
CONFIG_RATIONAL=y
@ -215,8 +213,6 @@ CONFIG_SYS_SUPPORTS_MIPS16=y
CONFIG_SYS_SUPPORTS_ZBOOT=y
CONFIG_TARGET_ISA_REV=2
CONFIG_TICK_CPU_ACCOUNTING=y
CONFIG_TIMER_OF=y
CONFIG_TIMER_PROBE=y
CONFIG_TINY_SRCU=y
CONFIG_USB_SUPPORT=y
CONFIG_USE_OF=y

384
target/linux/ramips/patches-6.6/001-v6.13-clocksource-drivers-ralink-Add-Ralink-System-Tick-Co.patch Normal file
View File

@ -0,0 +1,384 @@
From 57cbfd333c9d65bfab1a06b49c75536ee28dc2ce Mon Sep 17 00:00:00 2001
From: Sergio Paracuellos <sergio.paracuellos@gmail.com>
Date: Mon, 28 Oct 2024 21:36:43 +0100
Subject: clocksource/drivers/ralink: Add Ralink System Tick Counter driver
System Tick Counter is present on Ralink SoCs RT3352 and MT7620. This
driver has been in 'arch/mips/ralink' directory since the beggining of
Ralink architecture support. However, it can be moved into a more proper
place in 'drivers/clocksource'. Hence add it here adding also support for
compile test targets and reducing LOC in architecture code folder.
Signed-off-by: Sergio Paracuellos <sergio.paracuellos@gmail.com>
Link: https://lore.kernel.org/r/20241028203643.191268-2-sergio.paracuellos@gmail.com
Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
---
arch/mips/ralink/Kconfig | 7 --
arch/mips/ralink/Makefile | 2 -
arch/mips/ralink/cevt-rt3352.c | 153 -------------------------------------
drivers/clocksource/Kconfig | 9 +++
drivers/clocksource/Makefile | 1 +
drivers/clocksource/timer-ralink.c | 150 ++++++++++++++++++++++++++++++++++++
6 files changed, 160 insertions(+), 162 deletions(-)
delete mode 100644 arch/mips/ralink/cevt-rt3352.c
create mode 100644 drivers/clocksource/timer-ralink.c
--- a/arch/mips/ralink/Kconfig
+++ b/arch/mips/ralink/Kconfig
@@ -1,13 +1,6 @@
# SPDX-License-Identifier: GPL-2.0
if RALINK
-config CLKEVT_RT3352
- bool
- depends on SOC_RT305X || SOC_MT7620
- default y
- select TIMER_OF
- select CLKSRC_MMIO
-
config RALINK_ILL_ACC
bool
depends on SOC_RT305X
--- a/arch/mips/ralink/Makefile
+++ b/arch/mips/ralink/Makefile
@@ -10,8 +10,6 @@ ifndef CONFIG_MIPS_GIC
obj-y += clk.o timer.o
endif
-obj-$(CONFIG_CLKEVT_RT3352) += cevt-rt3352.o
-
obj-$(CONFIG_RALINK_ILL_ACC) += ill_acc.o
obj-$(CONFIG_IRQ_INTC) += irq.o
--- a/arch/mips/ralink/cevt-rt3352.c
+++ /dev/null
@@ -1,153 +0,0 @@
-/*
- * This file is subject to the terms and conditions of the GNU General Public
- * License. See the file "COPYING" in the main directory of this archive
- * for more details.
- *
- * Copyright (C) 2013 by John Crispin <john@phrozen.org>
- */
-
-#include <linux/clockchips.h>
-#include <linux/clocksource.h>
-#include <linux/interrupt.h>
-#include <linux/reset.h>
-#include <linux/init.h>
-#include <linux/time.h>
-#include <linux/of.h>
-#include <linux/of_irq.h>
-#include <linux/of_address.h>
-
-#include <asm/mach-ralink/ralink_regs.h>
-
-#define SYSTICK_FREQ (50 * 1000)
-
-#define SYSTICK_CONFIG 0x00
-#define SYSTICK_COMPARE 0x04
-#define SYSTICK_COUNT 0x08
-
-/* route systick irq to mips irq 7 instead of the r4k-timer */
-#define CFG_EXT_STK_EN 0x2
-/* enable the counter */
-#define CFG_CNT_EN 0x1
-
-struct systick_device {
- void __iomem *membase;
- struct clock_event_device dev;
- int irq_requested;
- int freq_scale;
-};
-
-static int systick_set_oneshot(struct clock_event_device *evt);
-static int systick_shutdown(struct clock_event_device *evt);
-
-static int systick_next_event(unsigned long delta,
- struct clock_event_device *evt)
-{
- struct systick_device *sdev;
- u32 count;
-
- sdev = container_of(evt, struct systick_device, dev);
- count = ioread32(sdev->membase + SYSTICK_COUNT);
- count = (count + delta) % SYSTICK_FREQ;
- iowrite32(count, sdev->membase + SYSTICK_COMPARE);
-
- return 0;
-}
-
-static void systick_event_handler(struct clock_event_device *dev)
-{
- /* noting to do here */
-}
-
-static irqreturn_t systick_interrupt(int irq, void *dev_id)
-{
- struct clock_event_device *dev = (struct clock_event_device *) dev_id;
-
- dev->event_handler(dev);
-
- return IRQ_HANDLED;
-}
-
-static struct systick_device systick = {
- .dev = {
- /*
- * cevt-r4k uses 300, make sure systick
- * gets used if available
- */
- .rating = 310,
- .features = CLOCK_EVT_FEAT_ONESHOT,
- .set_next_event = systick_next_event,
- .set_state_shutdown = systick_shutdown,
- .set_state_oneshot = systick_set_oneshot,
- .event_handler = systick_event_handler,
- },
-};
-
-static int systick_shutdown(struct clock_event_device *evt)
-{
- struct systick_device *sdev;
-
- sdev = container_of(evt, struct systick_device, dev);
-
- if (sdev->irq_requested)
- free_irq(systick.dev.irq, &systick.dev);
- sdev->irq_requested = 0;
- iowrite32(0, systick.membase + SYSTICK_CONFIG);
-
- return 0;
-}
-
-static int systick_set_oneshot(struct clock_event_device *evt)
-{
- const char *name = systick.dev.name;
- struct systick_device *sdev;
- int irq = systick.dev.irq;
-
- sdev = container_of(evt, struct systick_device, dev);
-
- if (!sdev->irq_requested) {
- if (request_irq(irq, systick_interrupt,
- IRQF_PERCPU | IRQF_TIMER, name, &systick.dev))
- pr_err("Failed to request irq %d (%s)\n", irq, name);
- }
- sdev->irq_requested = 1;
- iowrite32(CFG_EXT_STK_EN | CFG_CNT_EN,
- systick.membase + SYSTICK_CONFIG);
-
- return 0;
-}
-
-static int __init ralink_systick_init(struct device_node *np)
-{
- int ret;
-
- systick.membase = of_iomap(np, 0);
- if (!systick.membase)
- return -ENXIO;
-
- systick.dev.name = np->name;
- clockevents_calc_mult_shift(&systick.dev, SYSTICK_FREQ, 60);
- systick.dev.max_delta_ns = clockevent_delta2ns(0x7fff, &systick.dev);
- systick.dev.max_delta_ticks = 0x7fff;
- systick.dev.min_delta_ns = clockevent_delta2ns(0x3, &systick.dev);
- systick.dev.min_delta_ticks = 0x3;
- systick.dev.irq = irq_of_parse_and_map(np, 0);
- if (!systick.dev.irq) {
- pr_err("%pOFn: request_irq failed", np);
- return -EINVAL;
- }
-
- ret = clocksource_mmio_init(systick.membase + SYSTICK_COUNT, np->name,
- SYSTICK_FREQ, 301, 16,
- clocksource_mmio_readl_up);
- if (ret)
- return ret;
-
- clockevents_register_device(&systick.dev);
-
- pr_info("%pOFn: running - mult: %d, shift: %d\n",
- np, systick.dev.mult, systick.dev.shift);
-
- return 0;
-}
-
-TIMER_OF_DECLARE(systick, "ralink,cevt-systick", ralink_systick_init);
--- a/drivers/clocksource/Kconfig
+++ b/drivers/clocksource/Kconfig
@@ -732,4 +732,13 @@ config GOLDFISH_TIMER
help
Support for the timer/counter of goldfish-rtc
+config RALINK_TIMER
+ bool "Ralink System Tick Counter"
+ depends on SOC_RT305X || SOC_MT7620 || COMPILE_TEST
+ select CLKSRC_MMIO
+ select TIMER_OF
+ help
+ Enables support for system tick counter present on
+ Ralink SoCs RT3352 and MT7620.
+
endmenu
--- a/drivers/clocksource/Makefile
+++ b/drivers/clocksource/Makefile
@@ -89,3 +89,4 @@ obj-$(CONFIG_MSC313E_TIMER) += timer-ms
obj-$(CONFIG_GOLDFISH_TIMER) += timer-goldfish.o
obj-$(CONFIG_GXP_TIMER) += timer-gxp.o
obj-$(CONFIG_CLKSRC_LOONGSON1_PWM) += timer-loongson1-pwm.o
+obj-$(CONFIG_RALINK_TIMER) += timer-ralink.o
--- /dev/null
+++ b/drivers/clocksource/timer-ralink.c
@@ -0,0 +1,150 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Ralink System Tick Counter driver present on RT3352 and MT7620 SoCs.
+ *
+ * Copyright (C) 2013 by John Crispin <john@phrozen.org>
+ */
+
+#include <linux/clockchips.h>
+#include <linux/clocksource.h>
+#include <linux/interrupt.h>
+#include <linux/reset.h>
+#include <linux/init.h>
+#include <linux/time.h>
+#include <linux/of.h>
+#include <linux/of_irq.h>
+#include <linux/of_address.h>
+
+#define SYSTICK_FREQ (50 * 1000)
+
+#define SYSTICK_CONFIG 0x00
+#define SYSTICK_COMPARE 0x04
+#define SYSTICK_COUNT 0x08
+
+/* route systick irq to mips irq 7 instead of the r4k-timer */
+#define CFG_EXT_STK_EN 0x2
+/* enable the counter */
+#define CFG_CNT_EN 0x1
+
+struct systick_device {
+ void __iomem *membase;
+ struct clock_event_device dev;
+ int irq_requested;
+ int freq_scale;
+};
+
+static int systick_set_oneshot(struct clock_event_device *evt);
+static int systick_shutdown(struct clock_event_device *evt);
+
+static int systick_next_event(unsigned long delta,
+ struct clock_event_device *evt)
+{
+ struct systick_device *sdev;
+ u32 count;
+
+ sdev = container_of(evt, struct systick_device, dev);
+ count = ioread32(sdev->membase + SYSTICK_COUNT);
+ count = (count + delta) % SYSTICK_FREQ;
+ iowrite32(count, sdev->membase + SYSTICK_COMPARE);
+
+ return 0;
+}
+
+static void systick_event_handler(struct clock_event_device *dev)
+{
+ /* noting to do here */
+}
+
+static irqreturn_t systick_interrupt(int irq, void *dev_id)
+{
+ struct clock_event_device *dev = (struct clock_event_device *)dev_id;
+
+ dev->event_handler(dev);
+
+ return IRQ_HANDLED;
+}
+
+static struct systick_device systick = {
+ .dev = {
+ /*
+ * cevt-r4k uses 300, make sure systick
+ * gets used if available
+ */
+ .rating = 310,
+ .features = CLOCK_EVT_FEAT_ONESHOT,
+ .set_next_event = systick_next_event,
+ .set_state_shutdown = systick_shutdown,
+ .set_state_oneshot = systick_set_oneshot,
+ .event_handler = systick_event_handler,
+ },
+};
+
+static int systick_shutdown(struct clock_event_device *evt)
+{
+ struct systick_device *sdev;
+
+ sdev = container_of(evt, struct systick_device, dev);
+
+ if (sdev->irq_requested)
+ free_irq(systick.dev.irq, &systick.dev);
+ sdev->irq_requested = 0;
+ iowrite32(0, systick.membase + SYSTICK_CONFIG);
+
+ return 0;
+}
+
+static int systick_set_oneshot(struct clock_event_device *evt)
+{
+ const char *name = systick.dev.name;
+ struct systick_device *sdev;
+ int irq = systick.dev.irq;
+
+ sdev = container_of(evt, struct systick_device, dev);
+
+ if (!sdev->irq_requested) {
+ if (request_irq(irq, systick_interrupt,
+ IRQF_PERCPU | IRQF_TIMER, name, &systick.dev))
+ pr_err("Failed to request irq %d (%s)\n", irq, name);
+ }
+ sdev->irq_requested = 1;
+ iowrite32(CFG_EXT_STK_EN | CFG_CNT_EN,
+ systick.membase + SYSTICK_CONFIG);
+
+ return 0;
+}
+
+static int __init ralink_systick_init(struct device_node *np)
+{
+ int ret;
+
+ systick.membase = of_iomap(np, 0);
+ if (!systick.membase)
+ return -ENXIO;
+
+ systick.dev.name = np->name;
+ clockevents_calc_mult_shift(&systick.dev, SYSTICK_FREQ, 60);
+ systick.dev.max_delta_ns = clockevent_delta2ns(0x7fff, &systick.dev);
+ systick.dev.max_delta_ticks = 0x7fff;
+ systick.dev.min_delta_ns = clockevent_delta2ns(0x3, &systick.dev);
+ systick.dev.min_delta_ticks = 0x3;
+ systick.dev.irq = irq_of_parse_and_map(np, 0);
+ if (!systick.dev.irq) {
+ pr_err("%pOFn: request_irq failed", np);
+ return -EINVAL;
+ }
+
+ ret = clocksource_mmio_init(systick.membase + SYSTICK_COUNT, np->name,
+ SYSTICK_FREQ, 301, 16,
+ clocksource_mmio_readl_up);
+ if (ret)
+ return ret;
+
+ clockevents_register_device(&systick.dev);
+
+ pr_info("%pOFn: running - mult: %d, shift: %d\n",
+ np, systick.dev.mult, systick.dev.shift);
+
+ return 0;
+}
+
+TIMER_OF_DECLARE(systick, "ralink,cevt-systick", ralink_systick_init);

36
target/linux/ramips/patches-6.6/311-MIPS-use-set_mode-to-enable-disable-the-cevt-r4k-irq.patch
View File

@ -1,13 +1,11 @@
From ce3d4a4111a5f7e6b4e74bceae5faa6ce388e8ec Mon Sep 17 00:00:00 2001
From: John Crispin <blogic@openwrt.org>
Date: Sun, 14 Jul 2013 23:08:11 +0200
Subject: [PATCH 05/53] MIPS: use set_mode() to enable/disable the cevt-r4k
irq
Subject: [PATCH 1/2] MIPS: use set_mode() to enable/disable the cevt-r4k irq
Signed-off-by: John Crispin <blogic@openwrt.org>
---
arch/mips/kernel/cevt-r4k.c | 43 +++++++++++++++++++++++++++++++++++++
arch/mips/ralink/Kconfig | 5 +++++
drivers/clocksource/Kconfig | 5 +++++
2 files changed, 48 insertions(+)
--- a/arch/mips/kernel/cevt-r4k.c
@ -96,23 +94,21 @@ Signed-off-by: John Crispin <blogic@openwrt.org>
return 0;
}
--- a/arch/mips/ralink/Kconfig
+++ b/arch/mips/ralink/Kconfig
@@ -1,12 +1,17 @@
# SPDX-License-Identifier: GPL-2.0
if RALINK
--- a/drivers/clocksource/Kconfig
+++ b/drivers/clocksource/Kconfig
@@ -731,10 +731,15 @@ config GOLDFISH_TIMER
depends on RTC_DRV_GOLDFISH
help
Support for the timer/counter of goldfish-rtc
+
+config CEVT_SYSTICK_QUIRK
+ bool
+ default n
+
config CLKEVT_RT3352
bool
depends on SOC_RT305X || SOC_MT7620
default y
select TIMER_OF
select CLKSRC_MMIO
+ select CEVT_SYSTICK_QUIRK
config RALINK_ILL_ACC
bool
config RALINK_TIMER
bool "Ralink System Tick Counter"
depends on SOC_RT305X || SOC_MT7620 || COMPILE_TEST
+ select CEVT_SYSTICK_QUIRK
select CLKSRC_MMIO
select TIMER_OF
help

33
target/linux/ramips/patches-6.6/312-MIPS-ralink-add-cpu-frequency-scaling.patch
View File

@ -1,19 +1,26 @@
From bd30f19a006fb52bac80c6463c49dd2f4159f4ac Mon Sep 17 00:00:00 2001
From: John Crispin <blogic@openwrt.org>
Date: Sun, 28 Jul 2013 16:26:41 +0200
Subject: [PATCH 06/53] MIPS: ralink: add cpu frequency scaling
Subject: [PATCH 2/2] MIPS: ralink: add cpu frequency scaling
This feature will break udelay() and cause the delay loop to have longer delays
when the frequency is scaled causing a performance hit.
Signed-off-by: John Crispin <blogic@openwrt.org>
---
arch/mips/ralink/cevt-rt3352.c | 38 ++++++++++++++++++++++++++++++++++++++
1 file changed, 38 insertions(+)
drivers/clocksource/timer-ralink.c | 117 ++++++++++++++++++++++-------
1 file changed, 89 insertions(+), 28 deletions(-)
--- a/arch/mips/ralink/cevt-rt3352.c
+++ b/arch/mips/ralink/cevt-rt3352.c
@@ -29,6 +29,10 @@
--- a/drivers/clocksource/timer-ralink.c
+++ b/drivers/clocksource/timer-ralink.c
@@ -5,6 +5,7 @@
* Copyright (C) 2013 by John Crispin <john@phrozen.org>
*/
+#include <asm/mach-ralink/ralink_regs.h>
#include <linux/clockchips.h>
#include <linux/clocksource.h>
#include <linux/interrupt.h>
@@ -26,6 +27,10 @@
/* enable the counter */
#define CFG_CNT_EN 0x1
@ -24,7 +31,7 @@ Signed-off-by: John Crispin <blogic@openwrt.org>
struct systick_device {
void __iomem *membase;
struct clock_event_device dev;
@@ -36,21 +40,53 @@ struct systick_device {
@@ -33,21 +38,53 @@ struct systick_device {
int freq_scale;
};
@ -83,18 +90,18 @@ Signed-off-by: John Crispin <blogic@openwrt.org>
}
static void systick_event_handler(struct clock_event_device *dev)
@@ -60,20 +96,25 @@ static void systick_event_handler(struct
@@ -57,20 +94,25 @@ static void systick_event_handler(struct
static irqreturn_t systick_interrupt(int irq, void *dev_id)
{
- struct clock_event_device *dev = (struct clock_event_device *) dev_id;
- struct clock_event_device *dev = (struct clock_event_device *)dev_id;
+ int ret = 0;
+ struct clock_event_device *cdev;
+ struct systick_device *sdev;
- dev->event_handler(dev);
+ if (read_c0_cause() & STATUSF_IP7) {
+ cdev = (struct clock_event_device *) dev_id;
+ cdev = (struct clock_event_device *)dev_id;
+ sdev = container_of(cdev, struct systick_device, dev);
+
+ /* Clear Count/Compare Interrupt */
@ -117,7 +124,7 @@ Signed-off-by: John Crispin <blogic@openwrt.org>
.features = CLOCK_EVT_FEAT_ONESHOT,
.set_next_event = systick_next_event,
.set_state_shutdown = systick_shutdown,
@@ -91,7 +132,13 @@ static int systick_shutdown(struct clock
@@ -88,7 +130,13 @@ static int systick_shutdown(struct clock
if (sdev->irq_requested)
free_irq(systick.dev.irq, &systick.dev);
sdev->irq_requested = 0;
@ -132,7 +139,7 @@ Signed-off-by: John Crispin <blogic@openwrt.org>
return 0;
}
@@ -116,33 +163,46 @@ static int systick_set_oneshot(struct cl
@@ -113,33 +161,46 @@ static int systick_set_oneshot(struct cl
return 0;
}

4
target/linux/ramips/patches-6.6/316-arch-mips-do-not-select-illegal-access-driver-by-def.patch
View File

@ -11,8 +11,8 @@ Signed-off-by: John Crispin <blogic@openwrt.org>
--- a/arch/mips/ralink/Kconfig
+++ b/arch/mips/ralink/Kconfig
@@ -14,9 +14,9 @@ config CLKEVT_RT3352
select CEVT_SYSTICK_QUIRK
@@ -2,9 +2,9 @@
if RALINK
config RALINK_ILL_ACC
- bool

2
target/linux/ramips/rt305x/config-6.6
View File

@ -6,7 +6,6 @@ CONFIG_ARCH_MMAP_RND_COMPAT_BITS_MAX=15
CONFIG_ARCH_SUSPEND_POSSIBLE=y
CONFIG_CEVT_R4K=y
CONFIG_CEVT_SYSTICK_QUIRK=y
CONFIG_CLKEVT_RT3352=y
CONFIG_CLKSRC_MMIO=y
CONFIG_CLK_MTMIPS=y
CONFIG_CLONE_BACKWARDS=y
@ -160,6 +159,7 @@ CONFIG_PREEMPT_NONE_BUILD=y
CONFIG_PTP_1588_CLOCK_OPTIONAL=y
CONFIG_RALINK=y
# CONFIG_RALINK_ILL_ACC is not set
CONFIG_RALINK_TIMER=y
CONFIG_RALINK_WDT=y
CONFIG_RANDSTRUCT_NONE=y
CONFIG_RATIONAL=y