[PATCH v4 0/7] Add EcoNet EN751221 MIPS platform support

[PATCH v4 0/7] Add EcoNet EN751221 MIPS platform support

[Caleb James DeLisle]

EcoNet MIPS SoCs are big endian machines based on 34Kc and 1004Kc
processors. They are found in xDSL and xPON modems, and contain PCM
(VoIP), Ethernet, USB, GPIO, I2C, SPI (Flash), UART, and PCIe.

The EcoNet MIPS SoCs are divided broadly into two families, the
EN751221 family based on the 34Kc, and the EN751627 family based on
the 1004Kc. Individual SoCs within a family are very similar, only
with different peripherals.

This patchset adds basic "boots to a console" support for the EN751221
family and adds SmartFiber XP8421-B, a low cost commercially available
board that is useful for testing and development.

Note that Airoha (AN7523, AN7581) is similar to EcoNet in terms of
peripherals, and for historical reasons Airoha chips are sometimes
referred to with the EN75xx prefix. However this is a different
platform because Airoha chips are ARM based.

This patchset is against mips-next.

v3 -> v4
* Rebase to 3b3704261e851e25983860e4c352f1f73786f4ab
* Omit already accepted patches (thanks guys!):
  - https://patchwork.kernel.org/project/linux-mips/patch/20250330170306.2584136-2-cjd@cjdns.fr/
  - https://patchwork.kernel.org/project/linux-mips/patch/20250330170306.2584136-3-cjd@cjdns.fr/
  - https://patchwork.kernel.org/project/linux-mips/patch/20250330170306.2584136-4-cjd@cjdns.fr/

v2 -> v3
* econet,en751221-timer.yaml -> Improve code style
* vendor-prefixes.yaml -> Correct alphabetic order
* en751221.dtsi
  - interrupt-controller code style
  - serial: Explain reason for clock-frequency = <1843200>
* v3->v3 diff provided for reference
  - https://gist.github.com/cjdelisle/21c9f0cd225f499bdff3c574c7f185f2
* CC: linux-mediatek@lists.infradead.org who may be interested.

v1 -> v2
* Codestyle
  - Apply codestyle from "The tip tree handbook" and recommendations
  - Remove "_rai" and "_m" symbol suffixes which are not standard
* irq-econet-en751221.c
  - Use cleanup.h _guard() and _free()
  - Separate irq_domain_ops from irq_chip, eliminating econet_intc struct
  - Remove irqsave in econet_wreg, irqs are already disabled in mask/unmask
  - Add explainatory comments
  - Refactor shadow logic for clarity, e.g. INTC_NO_SHADOW -> NOT_PERCPU
  - Improve error handling in case of invalid DTS
* econet,timer-hpt.yaml
  - Rename to econet,timer-en751221.yaml
  - Impose rule: "reg" must have 1 item on EN751221 and 2 on EN751627
* timer-econet-hpt.c
  - Rename to timer-econet-en751221.c to follow naming scheme from DT
* econet,en751221-intc.yaml
  - Fix validation error from required: interrupt-parent
  - shadow-interrupts -> switch to uint32-matrix for list of pairs
* MAINTAINERS -> Fixed accidental F: MAINTAINERS
* Replace "test image" with device SmartFiber-XP8421-B
* Restructure arch/mips/econet/Kconfig per arch/mips/ralink example
* v1->v2 diff is offered for reference:
  - https://gist.github.com/cjdelisle/bb3acab78b5f70dcdfe5dd6338293efe


Caleb James DeLisle (7):
  dt-bindings: timer: Add EcoNet EN751221 "HPT" CPU Timer
  clocksource/drivers: Add EcoNet Timer HPT driver
  dt-bindings: mips: Add EcoNet platform binding
  mips: Add EcoNet MIPS platform support
  dt-bindings: vendor-prefixes: Add SmartFiber
  mips: dts: Add EcoNet DTS with EN751221 and SmartFiber XP8421-B board
  MAINTAINERS: Add entry for newly added EcoNet platform.

 .../devicetree/bindings/mips/econet.yaml      |  26 +++
 .../bindings/timer/econet,en751221-timer.yaml |  80 +++++++
 .../devicetree/bindings/vendor-prefixes.yaml  |   2 +
 MAINTAINERS                                   |  12 +
 arch/mips/Kbuild.platforms                    |   1 +
 arch/mips/Kconfig                             |  25 ++
 arch/mips/boot/compressed/uart-16550.c        |   5 +
 arch/mips/boot/dts/Makefile                   |   1 +
 arch/mips/boot/dts/econet/Makefile            |   2 +
 arch/mips/boot/dts/econet/en751221.dtsi       |  67 ++++++
 .../econet/en751221_smartfiber_xp8421-b.dts   |  19 ++
 arch/mips/econet/Kconfig                      |  48 ++++
 arch/mips/econet/Makefile                     |   2 +
 arch/mips/econet/Platform                     |   5 +
 arch/mips/econet/init.c                       |  78 +++++++
 drivers/clocksource/Kconfig                   |   8 +
 drivers/clocksource/Makefile                  |   1 +
 drivers/clocksource/timer-econet-en751221.c   | 216 ++++++++++++++++++
 18 files changed, 598 insertions(+)
 create mode 100644 Documentation/devicetree/bindings/mips/econet.yaml
 create mode 100644 Documentation/devicetree/bindings/timer/econet,en751221-timer.yaml
 create mode 100644 arch/mips/boot/dts/econet/Makefile
 create mode 100644 arch/mips/boot/dts/econet/en751221.dtsi
 create mode 100644 arch/mips/boot/dts/econet/en751221_smartfiber_xp8421-b.dts
 create mode 100644 arch/mips/econet/Kconfig
 create mode 100644 arch/mips/econet/Makefile
 create mode 100644 arch/mips/econet/Platform
 create mode 100644 arch/mips/econet/init.c
 create mode 100644 drivers/clocksource/timer-econet-en751221.c

-- 
2.39.5

[PATCH v4 1/7] dt-bindings: timer: Add EcoNet EN751221 "HPT" CPU Timer

[Caleb James DeLisle]

Add device tree bindings for the so-called high-precision timer (HPT)
in the EcoNet EN751221 SoC.

Signed-off-by: Caleb James DeLisle <cjd@cjdns.fr>
---
 .../bindings/timer/econet,en751221-timer.yaml | 80 +++++++++++++++++++
 1 file changed, 80 insertions(+)
 create mode 100644 Documentation/devicetree/bindings/timer/econet,en751221-timer.yaml

diff --git a/Documentation/devicetree/bindings/timer/econet,en751221-timer.yaml b/Documentation/devicetree/bindings/timer/econet,en751221-timer.yaml
new file mode 100644
index 000000000000..c1e7c2b6afde
--- /dev/null
+++ b/Documentation/devicetree/bindings/timer/econet,en751221-timer.yaml
@@ -0,0 +1,80 @@
+# SPDX-License-Identifier: (GPL-2.0 OR BSD-2-Clause)
+%YAML 1.2
+---
+$id: http://devicetree.org/schemas/timer/econet,en751221-timer.yaml#
+$schema: http://devicetree.org/meta-schemas/core.yaml#
+
+title: EcoNet EN751221 High Precision Timer (HPT)
+
+maintainers:
+  - Caleb James DeLisle <cjd@cjdns.fr>
+
+description:
+  The EcoNet High Precision Timer (HPT) is a timer peripheral found in various
+  EcoNet SoCs, including the EN751221 and EN751627 families. It provides per-VPE
+  count/compare registers and a per-CPU control register, with a single interrupt
+  line using a percpu-devid interrupt mechanism.
+
+properties:
+  compatible:
+    oneOf:
+      - const: econet,en751221-timer
+      - items:
+          - const: econet,en751627-timer
+          - const: econet,en751221-timer
+
+  reg:
+    minItems: 1
+    maxItems: 2
+
+  interrupts:
+    maxItems: 1
+    description: A percpu-devid timer interrupt shared across CPUs.
+
+  clocks:
+    maxItems: 1
+
+required:
+  - compatible
+  - reg
+  - interrupts
+  - clocks
+
+allOf:
+  - if:
+      properties:
+        compatible:
+          contains:
+            const: econet,en751627-timer
+    then:
+      properties:
+        reg:
+          items:
+            - description: VPE timers 0 and 1
+            - description: VPE timers 2 and 3
+    else:
+      properties:
+        reg:
+          items:
+            - description: VPE timers 0 and 1
+
+additionalProperties: false
+
+examples:
+  - |
+    timer@1fbf0400 {
+        compatible = "econet,en751627-timer", "econet,en751221-timer";
+        reg = <0x1fbf0400 0x100>, <0x1fbe0000 0x100>;
+        interrupt-parent = <&intc>;
+        interrupts = <30>;
+        clocks = <&hpt_clock>;
+    };
+  - |
+    timer@1fbf0400 {
+        compatible = "econet,en751221-timer";
+        reg = <0x1fbe0400 0x100>;
+        interrupt-parent = <&intc>;
+        interrupts = <30>;
+        clocks = <&hpt_clock>;
+    };
+...
-- 
2.39.5

[PATCH v4 2/7] clocksource/drivers: Add EcoNet Timer HPT driver

[Caleb James DeLisle]

Introduce a clocksource driver for the so-called high-precision timer (HPT)
in the EcoNet EN751221 MIPS SoC.

Signed-off-by: Caleb James DeLisle <cjd@cjdns.fr>
---
 drivers/clocksource/Kconfig                 |   8 +
 drivers/clocksource/Makefile                |   1 +
 drivers/clocksource/timer-econet-en751221.c | 216 ++++++++++++++++++++
 3 files changed, 225 insertions(+)
 create mode 100644 drivers/clocksource/timer-econet-en751221.c

diff --git a/drivers/clocksource/Kconfig b/drivers/clocksource/Kconfig
index 487c85259967..976afb0b2312 100644
--- a/drivers/clocksource/Kconfig
+++ b/drivers/clocksource/Kconfig
@@ -73,6 +73,14 @@ config DW_APB_TIMER_OF
 	select DW_APB_TIMER
 	select TIMER_OF
 
+config ECONET_EN751221_TIMER
+	bool "EcoNet EN751221 High Precision Timer" if COMPILE_TEST
+	depends on HAS_IOMEM
+	select CLKSRC_MMIO
+	select TIMER_OF
+	help
+	  Support for CPU timer found on EcoNet MIPS based SoCs.
+
 config FTTMR010_TIMER
 	bool "Faraday Technology timer driver" if COMPILE_TEST
 	depends on HAS_IOMEM
diff --git a/drivers/clocksource/Makefile b/drivers/clocksource/Makefile
index 43ef16a4efa6..d2998601eda5 100644
--- a/drivers/clocksource/Makefile
+++ b/drivers/clocksource/Makefile
@@ -17,6 +17,7 @@ obj-$(CONFIG_CLKBLD_I8253)	+= i8253.o
 obj-$(CONFIG_CLKSRC_MMIO)	+= mmio.o
 obj-$(CONFIG_DAVINCI_TIMER)	+= timer-davinci.o
 obj-$(CONFIG_DIGICOLOR_TIMER)	+= timer-digicolor.o
+obj-$(CONFIG_ECONET_EN751221_TIMER)	+= timer-econet-en751221.o
 obj-$(CONFIG_OMAP_DM_TIMER)	+= timer-ti-dm.o
 obj-$(CONFIG_OMAP_DM_SYSTIMER)	+= timer-ti-dm-systimer.o
 obj-$(CONFIG_DW_APB_TIMER)	+= dw_apb_timer.o
diff --git a/drivers/clocksource/timer-econet-en751221.c b/drivers/clocksource/timer-econet-en751221.c
new file mode 100644
index 000000000000..9cfeead09377
--- /dev/null
+++ b/drivers/clocksource/timer-econet-en751221.c
@@ -0,0 +1,216 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Timer present on EcoNet EN75xx MIPS based SoCs.
+ *
+ * Copyright (C) 2025 by Caleb James DeLisle <cjd@cjdns.fr>
+ */
+
+#include <linux/io.h>
+#include <linux/cpumask.h>
+#include <linux/interrupt.h>
+#include <linux/clockchips.h>
+#include <linux/sched_clock.h>
+#include <linux/of.h>
+#include <linux/of_irq.h>
+#include <linux/of_address.h>
+#include <linux/cpuhotplug.h>
+#include <linux/clk.h>
+
+#define ECONET_BITS			32
+#define ECONET_MIN_DELTA		0x00001000
+#define ECONET_MAX_DELTA		GENMASK(ECONET_BITS - 2, 0)
+/* 34Kc hardware has 1 block and 1004Kc has 2. */
+#define ECONET_NUM_BLOCKS		DIV_ROUND_UP(NR_CPUS, 2)
+
+static struct {
+	void __iomem	*membase[ECONET_NUM_BLOCKS];
+	u32		freq_hz;
+} econet_timer __ro_after_init;
+
+static DEFINE_PER_CPU(struct clock_event_device, econet_timer_pcpu);
+
+/* Each memory block has 2 timers, the order of registers is:
+ * CTL, CMR0, CNT0, CMR1, CNT1
+ */
+static inline void __iomem *reg_ctl(u32 timer_n)
+{
+	return econet_timer.membase[timer_n >> 1];
+}
+
+static inline void __iomem *reg_compare(u32 timer_n)
+{
+	return econet_timer.membase[timer_n >> 1] + (timer_n & 1) * 0x08 + 0x04;
+}
+
+static inline void __iomem *reg_count(u32 timer_n)
+{
+	return econet_timer.membase[timer_n >> 1] + (timer_n & 1) * 0x08 + 0x08;
+}
+
+static inline u32 ctl_bit_enabled(u32 timer_n)
+{
+	return 1U << (timer_n & 1);
+}
+
+static inline u32 ctl_bit_pending(u32 timer_n)
+{
+	return 1U << ((timer_n & 1) + 16);
+}
+
+static bool cevt_is_pending(int cpu_id)
+{
+	return ioread32(reg_ctl(cpu_id)) & ctl_bit_pending(cpu_id);
+}
+
+static irqreturn_t cevt_interrupt(int irq, void *dev_id)
+{
+	struct clock_event_device *dev = this_cpu_ptr(&econet_timer_pcpu);
+	int cpu = cpumask_first(dev->cpumask);
+
+	if (!cevt_is_pending(cpu)) {
+		pr_debug("%s IRQ %d on CPU %d is not pending\n", __func__, irq, cpu);
+		return IRQ_NONE;
+	}
+
+	iowrite32(ioread32(reg_count(cpu)), reg_compare(cpu));
+	dev->event_handler(dev);
+	return IRQ_HANDLED;
+}
+
+static int cevt_set_next_event(ulong delta, struct clock_event_device *dev)
+{
+	u32 next;
+	int cpu;
+
+	cpu = cpumask_first(dev->cpumask);
+	next = ioread32(reg_count(cpu)) + delta;
+	iowrite32(next, reg_compare(cpu));
+
+	if ((s32)(next - ioread32(reg_count(cpu))) < ECONET_MIN_DELTA / 2)
+		return -ETIME;
+
+	return 0;
+}
+
+static int cevt_init_cpu(uint cpu)
+{
+	struct clock_event_device *cd = &per_cpu(econet_timer_pcpu, cpu);
+	u32 reg;
+
+	pr_info("%s: Setting up clockevent for CPU %d\n", cd->name, cpu);
+
+	reg = ioread32(reg_ctl(cpu)) | ctl_bit_enabled(cpu);
+	iowrite32(reg, reg_ctl(cpu));
+
+	enable_percpu_irq(cd->irq, IRQ_TYPE_NONE);
+
+	/* Do this last because it synchronously configures the timer */
+	clockevents_config_and_register(
+		cd, econet_timer.freq_hz,
+		ECONET_MIN_DELTA, ECONET_MAX_DELTA);
+
+	return 0;
+}
+
+static u64 notrace sched_clock_read(void)
+{
+	/* Always read from clock zero no matter the CPU */
+	return (u64)ioread32(reg_count(0));
+}
+
+/* Init */
+
+static void __init cevt_dev_init(uint cpu)
+{
+	iowrite32(0, reg_count(cpu));
+	iowrite32(U32_MAX, reg_compare(cpu));
+}
+
+static int __init cevt_init(struct device_node *np)
+{
+	int i, irq, ret;
+
+	irq = irq_of_parse_and_map(np, 0);
+	if (irq <= 0) {
+		pr_err("%pOFn: irq_of_parse_and_map failed", np);
+		return -EINVAL;
+	}
+
+	ret = request_percpu_irq(irq, cevt_interrupt, np->name, &econet_timer_pcpu);
+
+	if (ret < 0) {
+		pr_err("%pOFn: IRQ %d setup failed (%d)\n", np, irq, ret);
+		goto err_unmap_irq;
+	}
+
+	for_each_possible_cpu(i) {
+		struct clock_event_device *cd = &per_cpu(econet_timer_pcpu, i);
+
+		cd->rating		= 310,
+		cd->features		= CLOCK_EVT_FEAT_ONESHOT |
+					  CLOCK_EVT_FEAT_C3STOP |
+					  CLOCK_EVT_FEAT_PERCPU;
+		cd->set_next_event	= cevt_set_next_event;
+		cd->irq			= irq;
+		cd->cpumask		= cpumask_of(i);
+		cd->name		= np->name;
+
+		cevt_dev_init(i);
+	}
+
+	cpuhp_setup_state(CPUHP_AP_MIPS_GIC_TIMER_STARTING,
+			  "clockevents/en75/timer:starting",
+			  cevt_init_cpu, NULL);
+	return 0;
+
+err_unmap_irq:
+	irq_dispose_mapping(irq);
+	return ret;
+}
+
+static int __init timer_init(struct device_node *np)
+{
+	int num_blocks = DIV_ROUND_UP(num_possible_cpus(), 2);
+	struct clk *clk;
+	int ret;
+
+	clk = of_clk_get(np, 0);
+	if (IS_ERR(clk)) {
+		pr_err("%pOFn: Failed to get CPU clock from DT %ld\n", np, PTR_ERR(clk));
+		return PTR_ERR(clk);
+	}
+
+	econet_timer.freq_hz = clk_get_rate(clk);
+
+	for (int i = 0; i < num_blocks; i++) {
+		econet_timer.membase[i] = of_iomap(np, i);
+		if (!econet_timer.membase[i]) {
+			pr_err("%pOFn: failed to map register [%d]\n", np, i);
+			return -ENXIO;
+		}
+	}
+
+	/* For clocksource purposes always read clock zero, whatever the CPU */
+	ret = clocksource_mmio_init(reg_count(0), np->name,
+				    econet_timer.freq_hz, 301, ECONET_BITS,
+				    clocksource_mmio_readl_up);
+	if (ret) {
+		pr_err("%pOFn: clocksource_mmio_init failed: %d", np, ret);
+		return ret;
+	}
+
+	ret = cevt_init(np);
+	if (ret < 0)
+		return ret;
+
+	sched_clock_register(sched_clock_read, ECONET_BITS,
+			     econet_timer.freq_hz);
+
+	pr_info("%pOFn: using %u.%03u MHz high precision timer\n", np,
+		econet_timer.freq_hz / 1000000,
+		(econet_timer.freq_hz / 1000) % 1000);
+
+	return 0;
+}
+
+TIMER_OF_DECLARE(econet_timer_hpt, "econet,en751221-timer", timer_init);
-- 
2.39.5

[PATCH v4 3/7] dt-bindings: mips: Add EcoNet platform binding

[Caleb James DeLisle]

Document the top-level device tree binding for EcoNet MIPS-based SoCs.

Signed-off-by: Caleb James DeLisle <cjd@cjdns.fr>
Reviewed-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>
---
 .../devicetree/bindings/mips/econet.yaml      | 26 +++++++++++++++++++
 1 file changed, 26 insertions(+)
 create mode 100644 Documentation/devicetree/bindings/mips/econet.yaml

diff --git a/Documentation/devicetree/bindings/mips/econet.yaml b/Documentation/devicetree/bindings/mips/econet.yaml
new file mode 100644
index 000000000000..d8181b58c781
--- /dev/null
+++ b/Documentation/devicetree/bindings/mips/econet.yaml
@@ -0,0 +1,26 @@
+# SPDX-License-Identifier: GPL-2.0-only OR BSD-2-Clause
+%YAML 1.2
+---
+$id: http://devicetree.org/schemas/mips/econet.yaml#
+$schema: http://devicetree.org/meta-schemas/core.yaml#
+
+title: EcoNet MIPS SoCs
+
+maintainers:
+  - Caleb James DeLisle <cjd@cjdns.fr>
+
+properties:
+  $nodename:
+    const: '/'
+
+  compatible:
+    oneOf:
+      - description: Boards with EcoNet EN751221 family SoC
+        items:
+          - enum:
+              - smartfiber,xp8421-b
+          - const: econet,en751221
+
+additionalProperties: true
+
+...
-- 
2.39.5

[PATCH v4 4/7] mips: Add EcoNet MIPS platform support

[Caleb James DeLisle]

Add platform support for EcoNet MIPS SoCs.

Signed-off-by: Caleb James DeLisle <cjd@cjdns.fr>
---
 arch/mips/Kbuild.platforms             |  1 +
 arch/mips/Kconfig                      | 25 +++++++++
 arch/mips/boot/compressed/uart-16550.c |  5 ++
 arch/mips/econet/Kconfig               | 37 ++++++++++++
 arch/mips/econet/Makefile              |  2 +
 arch/mips/econet/Platform              |  5 ++
 arch/mips/econet/init.c                | 78 ++++++++++++++++++++++++++
 7 files changed, 153 insertions(+)
 create mode 100644 arch/mips/econet/Kconfig
 create mode 100644 arch/mips/econet/Makefile
 create mode 100644 arch/mips/econet/Platform
 create mode 100644 arch/mips/econet/init.c

diff --git a/arch/mips/Kbuild.platforms b/arch/mips/Kbuild.platforms
index bca37ddf974b..41a00fa860c1 100644
--- a/arch/mips/Kbuild.platforms
+++ b/arch/mips/Kbuild.platforms
@@ -11,6 +11,7 @@ platform-$(CONFIG_CAVIUM_OCTEON_SOC)	+= cavium-octeon/
 platform-$(CONFIG_EYEQ)			+= mobileye/
 platform-$(CONFIG_MIPS_COBALT)		+= cobalt/
 platform-$(CONFIG_MACH_DECSTATION)	+= dec/
+platform-$(CONFIG_ECONET)		+= econet/
 platform-$(CONFIG_MIPS_GENERIC)		+= generic/
 platform-$(CONFIG_MACH_JAZZ)		+= jazz/
 platform-$(CONFIG_LANTIQ)		+= lantiq/
diff --git a/arch/mips/Kconfig b/arch/mips/Kconfig
index e0e6ce2592b4..c3dbdc808664 100644
--- a/arch/mips/Kconfig
+++ b/arch/mips/Kconfig
@@ -391,6 +391,30 @@ config MACH_DECSTATION
 
 	  otherwise choose R3000.
 
+config ECONET
+	bool "EcoNet MIPS family"
+	select BOOT_RAW
+	select CPU_BIG_ENDIAN
+	select DEBUG_ZBOOT
+	select EARLY_PRINTK_8250
+	select ECONET_EN751221_TIMER
+	select SERIAL_OF_PLATFORM
+	select SYS_SUPPORTS_BIG_ENDIAN
+	select SYS_HAS_CPU_MIPS32_R1
+	select SYS_HAS_CPU_MIPS32_R2
+	select SYS_HAS_EARLY_PRINTK
+	select SYS_SUPPORTS_32BIT_KERNEL
+	select SYS_SUPPORTS_MIPS16
+	select SYS_SUPPORTS_ZBOOT_UART16550
+	select USE_GENERIC_EARLY_PRINTK_8250
+	select USE_OF
+	help
+	  EcoNet EN75xx MIPS devices are big endian MIPS machines used
+	  in XPON (fiber) and DSL applications. They have SPI, PCI, USB,
+	  GPIO, and Ethernet, with optional XPON, DSL, and VoIP DSP cores.
+	  Don't confuse these with the Airoha ARM devices sometimes referred
+	  to as "EcoNet", this family is for MIPS based devices only.
+
 config MACH_JAZZ
 	bool "Jazz family of machines"
 	select ARC_MEMORY
@@ -1021,6 +1045,7 @@ source "arch/mips/ath79/Kconfig"
 source "arch/mips/bcm47xx/Kconfig"
 source "arch/mips/bcm63xx/Kconfig"
 source "arch/mips/bmips/Kconfig"
+source "arch/mips/econet/Kconfig"
 source "arch/mips/generic/Kconfig"
 source "arch/mips/ingenic/Kconfig"
 source "arch/mips/jazz/Kconfig"
diff --git a/arch/mips/boot/compressed/uart-16550.c b/arch/mips/boot/compressed/uart-16550.c
index db618e72a0c4..529e77a6487c 100644
--- a/arch/mips/boot/compressed/uart-16550.c
+++ b/arch/mips/boot/compressed/uart-16550.c
@@ -20,6 +20,11 @@
 #define PORT(offset) (CKSEG1ADDR(INGENIC_UART_BASE_ADDR) + (4 * offset))
 #endif
 
+#ifdef CONFIG_ECONET
+#define EN75_UART_BASE	0x1fbf0003
+#define PORT(offset)	(CKSEG1ADDR(EN75_UART_BASE) + (4 * (offset)))
+#endif
+
 #ifndef IOTYPE
 #define IOTYPE char
 #endif
diff --git a/arch/mips/econet/Kconfig b/arch/mips/econet/Kconfig
new file mode 100644
index 000000000000..d03f90f3daa4
--- /dev/null
+++ b/arch/mips/econet/Kconfig
@@ -0,0 +1,37 @@
+# SPDX-License-Identifier: GPL-2.0
+if ECONET
+
+choice
+	prompt "EcoNet SoC selection"
+	default SOC_ECONET_EN751221
+	help
+	  Select EcoNet MIPS SoC type. Individual SoCs within a family are
+	  very similar, so is it enough to select the right family, and
+	  then customize to the specific SoC using the device tree only.
+
+	config SOC_ECONET_EN751221
+		bool "EN751221 family"
+		select COMMON_CLK
+		select ECONET_EN751221_INTC
+		select IRQ_MIPS_CPU
+		select SMP
+		select SMP_UP
+		select SYS_SUPPORTS_SMP
+		help
+		  The EN751221 family includes EN7512, RN7513, EN7521, EN7526.
+		  They are based on single core MIPS 34Kc processors. To boot
+		  this kernel, you will need a device tree such as
+		  MIPS_RAW_APPENDED_DTB=y, and a root filesystem.
+endchoice
+
+choice
+	prompt "Devicetree selection"
+	default DTB_ECONET_NONE
+	help
+	  Select the devicetree.
+
+	config DTB_ECONET_NONE
+		bool "None"
+endchoice
+
+endif
diff --git a/arch/mips/econet/Makefile b/arch/mips/econet/Makefile
new file mode 100644
index 000000000000..7e4529e7d3d7
--- /dev/null
+++ b/arch/mips/econet/Makefile
@@ -0,0 +1,2 @@
+
+obj-y := init.o
diff --git a/arch/mips/econet/Platform b/arch/mips/econet/Platform
new file mode 100644
index 000000000000..ea5616447bcd
--- /dev/null
+++ b/arch/mips/econet/Platform
@@ -0,0 +1,5 @@
+# To address a 7.2MB kernel size limit in the EcoNet SDK bootloader,
+# we put the load address well above where the bootloader loads and then use
+# zboot. So please set CONFIG_ZBOOT_LOAD_ADDRESS to the address where your
+# bootloader actually places the kernel.
+load-$(CONFIG_ECONET)	+= 0xffffffff81000000
diff --git a/arch/mips/econet/init.c b/arch/mips/econet/init.c
new file mode 100644
index 000000000000..6f43ffb209cb
--- /dev/null
+++ b/arch/mips/econet/init.c
@@ -0,0 +1,78 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * EcoNet setup code
+ *
+ * Copyright (C) 2025 Caleb James DeLisle <cjd@cjdns.fr>
+ */
+
+#include <linux/init.h>
+#include <linux/of_clk.h>
+#include <linux/irqchip.h>
+
+#include <asm/addrspace.h>
+#include <asm/io.h>
+#include <asm/bootinfo.h>
+#include <asm/time.h>
+#include <asm/prom.h>
+#include <asm/smp-ops.h>
+#include <asm/reboot.h>
+
+#define CR_AHB_RSTCR		((void __iomem *)CKSEG1ADDR(0x1fb00040))
+#define RESET			BIT(31)
+
+#define UART_BASE		CKSEG1ADDR(0x1fbf0003)
+#define UART_REG_SHIFT		2
+
+static void hw_reset(char *command)
+{
+	iowrite32(RESET, CR_AHB_RSTCR);
+}
+
+/* 1. Bring up early printk. */
+void __init prom_init(void)
+{
+	setup_8250_early_printk_port(UART_BASE, UART_REG_SHIFT, 0);
+	_machine_restart = hw_reset;
+}
+
+/* 2. Parse the DT and find memory */
+void __init plat_mem_setup(void)
+{
+	void *dtb;
+
+	set_io_port_base(KSEG1);
+
+	dtb = get_fdt();
+	if (!dtb)
+		panic("no dtb found");
+
+	__dt_setup_arch(dtb);
+
+	early_init_dt_scan_memory();
+}
+
+/* 3. Overload __weak device_tree_init(), add SMP_UP ops */
+void __init device_tree_init(void)
+{
+	unflatten_and_copy_device_tree();
+
+	register_up_smp_ops();
+}
+
+const char *get_system_type(void)
+{
+	return "EcoNet-EN75xx";
+}
+
+/* 4. Initialize the IRQ subsystem */
+void __init arch_init_irq(void)
+{
+	irqchip_init();
+}
+
+/* 5. Timers */
+void __init plat_time_init(void)
+{
+	of_clk_init(NULL);
+	timer_probe();
+}
-- 
2.39.5

[PATCH v4 5/7] dt-bindings: vendor-prefixes: Add SmartFiber

[Caleb James DeLisle]

Add "smartfiber" vendor prefix for manufactorer of EcoNet based boards.

Signed-off-by: Caleb James DeLisle <cjd@cjdns.fr>
Acked-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>
---
 Documentation/devicetree/bindings/vendor-prefixes.yaml | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/Documentation/devicetree/bindings/vendor-prefixes.yaml b/Documentation/devicetree/bindings/vendor-prefixes.yaml
index 86f6a19b28ae..421fd5c2e41c 100644
--- a/Documentation/devicetree/bindings/vendor-prefixes.yaml
+++ b/Documentation/devicetree/bindings/vendor-prefixes.yaml
@@ -1396,6 +1396,8 @@ patternProperties:
     description: SKOV A/S
   "^skyworks,.*":
     description: Skyworks Solutions, Inc.
+  "^smartfiber,.*":
+    description: ShenZhen Smartfiber Technology Co, Ltd.
   "^smartlabs,.*":
     description: SmartLabs LLC
   "^smartrg,.*":
-- 
2.39.5

[PATCH v4 6/7] mips: dts: Add EcoNet DTS with EN751221 and SmartFiber XP8421-B board

[Caleb James DeLisle]

Add DTS files in support of EcoNet platform, including SmartFiber XP8421-B,
a low cost commercially available board based on EN751221.

Signed-off-by: Caleb James DeLisle <cjd@cjdns.fr>
---
 arch/mips/boot/dts/Makefile                   |  1 +
 arch/mips/boot/dts/econet/Makefile            |  2 +
 arch/mips/boot/dts/econet/en751221.dtsi       | 67 +++++++++++++++++++
 .../econet/en751221_smartfiber_xp8421-b.dts   | 19 ++++++
 arch/mips/econet/Kconfig                      | 11 +++
 5 files changed, 100 insertions(+)
 create mode 100644 arch/mips/boot/dts/econet/Makefile
 create mode 100644 arch/mips/boot/dts/econet/en751221.dtsi
 create mode 100644 arch/mips/boot/dts/econet/en751221_smartfiber_xp8421-b.dts

diff --git a/arch/mips/boot/dts/Makefile b/arch/mips/boot/dts/Makefile
index ff468439a8c4..7375c6ced82b 100644
--- a/arch/mips/boot/dts/Makefile
+++ b/arch/mips/boot/dts/Makefile
@@ -1,6 +1,7 @@
 # SPDX-License-Identifier: GPL-2.0
 subdir-$(CONFIG_BMIPS_GENERIC)		+= brcm
 subdir-$(CONFIG_CAVIUM_OCTEON_SOC)	+= cavium-octeon
+subdir-$(CONFIG_ECONET)			+= econet
 subdir-$(CONFIG_EYEQ)			+= mobileye
 subdir-$(CONFIG_FIT_IMAGE_FDT_MARDUK)   += img
 subdir-$(CONFIG_FIT_IMAGE_FDT_BOSTON)	+= img
diff --git a/arch/mips/boot/dts/econet/Makefile b/arch/mips/boot/dts/econet/Makefile
new file mode 100644
index 000000000000..b467d5624e39
--- /dev/null
+++ b/arch/mips/boot/dts/econet/Makefile
@@ -0,0 +1,2 @@
+# SPDX-License-Identifier: GPL-2.0
+dtb-$(CONFIG_DTB_ECONET_SMARTFIBER_XP8421_B)	+= en751221_smartfiber_xp8421-b.dtb
diff --git a/arch/mips/boot/dts/econet/en751221.dtsi b/arch/mips/boot/dts/econet/en751221.dtsi
new file mode 100644
index 000000000000..66197e73d4f0
--- /dev/null
+++ b/arch/mips/boot/dts/econet/en751221.dtsi
@@ -0,0 +1,67 @@
+// SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
+/dts-v1/;
+
+/ {
+	compatible = "econet,en751221";
+	#address-cells = <1>;
+	#size-cells = <1>;
+
+	hpt_clock: clock {
+		compatible = "fixed-clock";
+		#clock-cells = <0>;
+		clock-frequency = <200000000>;  /* 200 MHz */
+	};
+
+	cpus: cpus {
+		#address-cells = <1>;
+		#size-cells = <0>;
+
+		cpu@0 {
+			device_type = "cpu";
+			compatible = "mips,mips24KEc";
+			reg = <0>;
+		};
+	};
+
+	cpuintc: interrupt-controller {
+		compatible = "mti,cpu-interrupt-controller";
+		interrupt-controller;
+		#address-cells = <0>;
+		#interrupt-cells = <1>;
+	};
+
+	intc: interrupt-controller@1fb40000 {
+		compatible = "econet,en751221-intc";
+		reg = <0x1fb40000 0x100>;
+		interrupt-parent = <&cpuintc>;
+		interrupts = <2>;
+
+		interrupt-controller;
+		#interrupt-cells = <1>;
+		econet,shadow-interrupts = <7 2>, <8 3>, <13 12>, <30 29>;
+	};
+
+	uart: serial@1fbf0000 {
+		compatible = "ns16550";
+		reg = <0x1fbf0000 0x30>;
+		reg-io-width = <4>;
+		reg-shift = <2>;
+		interrupt-parent = <&intc>;
+		interrupts = <0>;
+		/*
+		 * Conversion of baud rate to clock frequency requires a
+		 * computation that is not in the ns16550 driver, so this
+		 * uart is fixed at 115200 baud.
+		 */
+		clock-frequency = <1843200>;
+	};
+
+	timer_hpt: timer@1fbf0400 {
+		compatible = "econet,en751221-timer";
+		reg = <0x1fbf0400 0x100>;
+
+		interrupt-parent = <&intc>;
+		interrupts = <30>;
+		clocks = <&hpt_clock>;
+	};
+};
diff --git a/arch/mips/boot/dts/econet/en751221_smartfiber_xp8421-b.dts b/arch/mips/boot/dts/econet/en751221_smartfiber_xp8421-b.dts
new file mode 100644
index 000000000000..8223c5bce67f
--- /dev/null
+++ b/arch/mips/boot/dts/econet/en751221_smartfiber_xp8421-b.dts
@@ -0,0 +1,19 @@
+// SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
+/dts-v1/;
+
+#include "en751221.dtsi"
+
+/ {
+	model = "SmartFiber XP8421-B";
+	compatible = "smartfiber,xp8421-b", "econet,en751221";
+
+	memory@0 {
+		device_type = "memory";
+		reg = <0x00000000 0x1c000000>;
+	};
+
+	chosen {
+		stdout-path = "/serial@1fbf0000:115200";
+		linux,usable-memory-range = <0x00020000 0x1bfe0000>;
+	};
+};
diff --git a/arch/mips/econet/Kconfig b/arch/mips/econet/Kconfig
index d03f90f3daa4..fd69884cc9a8 100644
--- a/arch/mips/econet/Kconfig
+++ b/arch/mips/econet/Kconfig
@@ -32,6 +32,17 @@ choice
 
 	config DTB_ECONET_NONE
 		bool "None"
+
+	config DTB_ECONET_SMARTFIBER_XP8421_B
+		bool "EN751221 SmartFiber XP8421-B"
+		depends on SOC_ECONET_EN751221
+		select BUILTIN_DTB
+		help
+		  The SmartFiber XP8421-B is a device based on the EN751221 SoC.
+		  It has 512MB of memory and 256MB of NAND flash. This kernel
+		  needs only an appended initramfs to boot. It can be loaded
+		  through XMODEM and booted from memory in the bootloader, or
+		  it can be packed in tclinux.trx format and written to flash.
 endchoice
 
 endif
-- 
2.39.5

[PATCH v4 7/7] MAINTAINERS: Add entry for newly added EcoNet platform.

[Caleb James DeLisle]

Add a MAINTAINERS entry as part of integration of the EcoNet MIPS platform.

Signed-off-by: Caleb James DeLisle <cjd@cjdns.fr>
---
 MAINTAINERS | 12 ++++++++++++
 1 file changed, 12 insertions(+)

diff --git a/MAINTAINERS b/MAINTAINERS
index 96b827049501..5b2536150996 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -8352,6 +8352,18 @@ W:	https://linuxtv.org
 Q:	http://patchwork.linuxtv.org/project/linux-media/list/
 F:	drivers/media/dvb-frontends/ec100*
 
+ECONET MIPS PLATFORM
+M:	Caleb James DeLisle <cjd@cjdns.fr>
+L:	linux-mips@vger.kernel.org
+S:	Maintained
+F:	Documentation/devicetree/bindings/interrupt-controller/econet,en751221-intc.yaml
+F:	Documentation/devicetree/bindings/mips/econet.yaml
+F:	Documentation/devicetree/bindings/timer/econet,en751221-timer.yaml
+F:	arch/mips/boot/dts/econet/
+F:	arch/mips/econet/
+F:	drivers/clocksource/timer-econet-en751221.c
+F:	drivers/irqchip/irq-econet-en751221.c
+
 ECRYPT FILE SYSTEM
 M:	Tyler Hicks <code@tyhicks.com>
 L:	ecryptfs@vger.kernel.org
-- 
2.39.5

Re: [PATCH v4 1/7] dt-bindings: timer: Add EcoNet EN751221 "HPT" CPU Timer

[Krzysztof Kozlowski]

On Wed, Apr 30, 2025 at 01:34:27PM GMT, Caleb James DeLisle wrote:
> Add device tree bindings for the so-called high-precision timer (HPT)
> in the EcoNet EN751221 SoC.
> 
> Signed-off-by: Caleb James DeLisle <cjd@cjdns.fr>
> ---
>  .../bindings/timer/econet,en751221-timer.yaml | 80 +++++++++++++++++++
>  1 file changed, 80 insertions(+)
>  create mode 100644 Documentation/devicetree/bindings/timer/econet,en751221-timer.yaml
> 

What changed? Nothing explains dropping the tag.

<form letter>
This is a friendly reminder during the review process.

It looks like you received a tag and forgot to add it.

If you do not know the process, here is a short explanation:
Please add Acked-by/Reviewed-by/Tested-by tags when posting new
versions of patchset, under or above your Signed-off-by tag, unless
patch changed significantly (e.g. new properties added to the DT
bindings). Tag is "received", when provided in a message replied to you
on the mailing list. Tools like b4 can help here. However, there's no
need to repost patches *only* to add the tags. The upstream maintainer
will do that for tags received on the version they apply.

Please read:
https://elixir.bootlin.com/linux/v6.12-rc3/source/Documentation/process/submitting-patches.rst#L577

If a tag was not added on purpose, please state why and what changed.
</form letter>

Best regards,
Krzysztof

Re: [PATCH v4 1/7] dt-bindings: timer: Add EcoNet EN751221 "HPT" CPU Timer

[Caleb James DeLisle]

On 01/05/2025 12:58, Krzysztof Kozlowski wrote:
> On Wed, Apr 30, 2025 at 01:34:27PM GMT, Caleb James DeLisle wrote:
>> Add device tree bindings for the so-called high-precision timer (HPT)
>> in the EcoNet EN751221 SoC.
>>
>> Signed-off-by: Caleb James DeLisle <cjd@cjdns.fr>
>> ---
>>   .../bindings/timer/econet,en751221-timer.yaml | 80 +++++++++++++++++++
>>   1 file changed, 80 insertions(+)
>>   create mode 100644 Documentation/devicetree/bindings/timer/econet,en751221-timer.yaml
>>
> What changed? Nothing explains dropping the tag.


Sorry I lost track of it, I will re-send with it attached again.

Thanks,

Caleb


>
> <form letter>
> This is a friendly reminder during the review process.
>
> It looks like you received a tag and forgot to add it.
>
> If you do not know the process, here is a short explanation:
> Please add Acked-by/Reviewed-by/Tested-by tags when posting new
> versions of patchset, under or above your Signed-off-by tag, unless
> patch changed significantly (e.g. new properties added to the DT
> bindings). Tag is "received", when provided in a message replied to you
> on the mailing list. Tools like b4 can help here. However, there's no
> need to repost patches *only* to add the tags. The upstream maintainer
> will do that for tags received on the version they apply.
>
> Please read:
> https://elixir.bootlin.com/linux/v6.12-rc3/source/Documentation/process/submitting-patches.rst#L577
>
> If a tag was not added on purpose, please state why and what changed.
> </form letter>
>
> Best regards,
> Krzysztof
>
>

Re: [PATCH v4 1/7] dt-bindings: timer: Add EcoNet EN751221 "HPT" CPU Timer

[Krzysztof Kozlowski]

On 30/04/2025 15:34, Caleb James DeLisle wrote:
> Add device tree bindings for the so-called high-precision timer (HPT)
> in the EcoNet EN751221 SoC.
> 
> Signed-off-by: Caleb James DeLisle <cjd@cjdns.fr>

Reviewed-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>

Best regards,
Krzysztof

Re: [PATCH v4 5/7] dt-bindings: vendor-prefixes: Add SmartFiber

[Philippe Mathieu-Daudé]

On 30/4/25 15:34, Caleb James DeLisle wrote:
> Add "smartfiber" vendor prefix for manufactorer of EcoNet based boards.
> 
> Signed-off-by: Caleb James DeLisle <cjd@cjdns.fr>
> Acked-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>
> ---
>   Documentation/devicetree/bindings/vendor-prefixes.yaml | 2 ++
>   1 file changed, 2 insertions(+)

Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>

Re: [PATCH v4 7/7] MAINTAINERS: Add entry for newly added EcoNet platform.

[Philippe Mathieu-Daudé]

On 30/4/25 15:34, Caleb James DeLisle wrote:
> Add a MAINTAINERS entry as part of integration of the EcoNet MIPS platform.
> 
> Signed-off-by: Caleb James DeLisle <cjd@cjdns.fr>
> ---
>   MAINTAINERS | 12 ++++++++++++
>   1 file changed, 12 insertions(+)

Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>

Re: [PATCH v4 2/7] clocksource/drivers: Add EcoNet Timer HPT driver

[Daniel Lezcano]

On Wed, Apr 30, 2025 at 01:34:28PM +0000, Caleb James DeLisle wrote:
> Introduce a clocksource driver for the so-called high-precision timer (HPT)
> in the EcoNet EN751221 MIPS SoC.

As a new driver, please document the timer (up - down ?, SPI/PPI, etc
...) that will help to understand the code more easily, especially the
reg_* functions (purposes?).

> Signed-off-by: Caleb James DeLisle <cjd@cjdns.fr>
> ---
>  drivers/clocksource/Kconfig                 |   8 +
>  drivers/clocksource/Makefile                |   1 +
>  drivers/clocksource/timer-econet-en751221.c | 216 ++++++++++++++++++++
>  3 files changed, 225 insertions(+)
>  create mode 100644 drivers/clocksource/timer-econet-en751221.c
> 
> diff --git a/drivers/clocksource/Kconfig b/drivers/clocksource/Kconfig
> index 487c85259967..976afb0b2312 100644
> --- a/drivers/clocksource/Kconfig
> +++ b/drivers/clocksource/Kconfig
> @@ -73,6 +73,14 @@ config DW_APB_TIMER_OF
>  	select DW_APB_TIMER
>  	select TIMER_OF
>  
> +config ECONET_EN751221_TIMER
> +	bool "EcoNet EN751221 High Precision Timer" if COMPILE_TEST
> +	depends on HAS_IOMEM
> +	select CLKSRC_MMIO
> +	select TIMER_OF
> +	help
> +	  Support for CPU timer found on EcoNet MIPS based SoCs.
> +
>  config FTTMR010_TIMER
>  	bool "Faraday Technology timer driver" if COMPILE_TEST
>  	depends on HAS_IOMEM
> diff --git a/drivers/clocksource/Makefile b/drivers/clocksource/Makefile
> index 43ef16a4efa6..d2998601eda5 100644
> --- a/drivers/clocksource/Makefile
> +++ b/drivers/clocksource/Makefile
> @@ -17,6 +17,7 @@ obj-$(CONFIG_CLKBLD_I8253)	+= i8253.o
>  obj-$(CONFIG_CLKSRC_MMIO)	+= mmio.o
>  obj-$(CONFIG_DAVINCI_TIMER)	+= timer-davinci.o
>  obj-$(CONFIG_DIGICOLOR_TIMER)	+= timer-digicolor.o
> +obj-$(CONFIG_ECONET_EN751221_TIMER)	+= timer-econet-en751221.o
>  obj-$(CONFIG_OMAP_DM_TIMER)	+= timer-ti-dm.o
>  obj-$(CONFIG_OMAP_DM_SYSTIMER)	+= timer-ti-dm-systimer.o
>  obj-$(CONFIG_DW_APB_TIMER)	+= dw_apb_timer.o
> diff --git a/drivers/clocksource/timer-econet-en751221.c b/drivers/clocksource/timer-econet-en751221.c
> new file mode 100644
> index 000000000000..9cfeead09377
> --- /dev/null
> +++ b/drivers/clocksource/timer-econet-en751221.c
> @@ -0,0 +1,216 @@
> +// SPDX-License-Identifier: GPL-2.0
> +/*
> + * Timer present on EcoNet EN75xx MIPS based SoCs.
> + *
> + * Copyright (C) 2025 by Caleb James DeLisle <cjd@cjdns.fr>
> + */
> +
> +#include <linux/io.h>
> +#include <linux/cpumask.h>
> +#include <linux/interrupt.h>
> +#include <linux/clockchips.h>
> +#include <linux/sched_clock.h>
> +#include <linux/of.h>
> +#include <linux/of_irq.h>
> +#include <linux/of_address.h>
> +#include <linux/cpuhotplug.h>
> +#include <linux/clk.h>
> +
> +#define ECONET_BITS			32
> +#define ECONET_MIN_DELTA		0x00001000
> +#define ECONET_MAX_DELTA		GENMASK(ECONET_BITS - 2, 0)
> +/* 34Kc hardware has 1 block and 1004Kc has 2. */
> +#define ECONET_NUM_BLOCKS		DIV_ROUND_UP(NR_CPUS, 2)
> +
> +static struct {
> +	void __iomem	*membase[ECONET_NUM_BLOCKS];
> +	u32		freq_hz;
> +} econet_timer __ro_after_init;
> +
> +static DEFINE_PER_CPU(struct clock_event_device, econet_timer_pcpu);
> +
> +/* Each memory block has 2 timers, the order of registers is:
> + * CTL, CMR0, CNT0, CMR1, CNT1
> + */
> +static inline void __iomem *reg_ctl(u32 timer_n)
> +{
> +	return econet_timer.membase[timer_n >> 1];
> +}
> +
> +static inline void __iomem *reg_compare(u32 timer_n)
> +{
> +	return econet_timer.membase[timer_n >> 1] + (timer_n & 1) * 0x08 + 0x04;
> +}
> +
> +static inline void __iomem *reg_count(u32 timer_n)
> +{
> +	return econet_timer.membase[timer_n >> 1] + (timer_n & 1) * 0x08 + 0x08;
> +}
> +
> +static inline u32 ctl_bit_enabled(u32 timer_n)
> +{
> +	return 1U << (timer_n & 1);
> +}
> +
> +static inline u32 ctl_bit_pending(u32 timer_n)
> +{
> +	return 1U << ((timer_n & 1) + 16);
> +}
> +
> +static bool cevt_is_pending(int cpu_id)
> +{
> +	return ioread32(reg_ctl(cpu_id)) & ctl_bit_pending(cpu_id);
> +}
> +
> +static irqreturn_t cevt_interrupt(int irq, void *dev_id)
> +{
> +	struct clock_event_device *dev = this_cpu_ptr(&econet_timer_pcpu);
> +	int cpu = cpumask_first(dev->cpumask);
> +
> +	if (!cevt_is_pending(cpu)) {
> +		pr_debug("%s IRQ %d on CPU %d is not pending\n", __func__, irq, cpu);
> +		return IRQ_NONE;
> +	}

How this can happen ? Can this interrupt be shared ?

The system will account this as a spurious interrupt, the debug
message is not needed.

> +	iowrite32(ioread32(reg_count(cpu)), reg_compare(cpu));
> +	dev->event_handler(dev);
> +	return IRQ_HANDLED;
> +}
> +
> +static int cevt_set_next_event(ulong delta, struct clock_event_device *dev)
> +{
> +	u32 next;
> +	int cpu;
> +
> +	cpu = cpumask_first(dev->cpumask);
> +	next = ioread32(reg_count(cpu)) + delta;
> +	iowrite32(next, reg_compare(cpu));
> +
> +	if ((s32)(next - ioread32(reg_count(cpu))) < ECONET_MIN_DELTA / 2)
> +		return -ETIME;
> +
> +	return 0;
> +}
> +
> +static int cevt_init_cpu(uint cpu)
> +{
> +	struct clock_event_device *cd = &per_cpu(econet_timer_pcpu, cpu);
> +	u32 reg;
> +
> +	pr_info("%s: Setting up clockevent for CPU %d\n", cd->name, cpu);

That is more debug information

> +	reg = ioread32(reg_ctl(cpu)) | ctl_bit_enabled(cpu);
> +	iowrite32(reg, reg_ctl(cpu));
> +
> +	enable_percpu_irq(cd->irq, IRQ_TYPE_NONE);
> +
> +	/* Do this last because it synchronously configures the timer */
> +	clockevents_config_and_register(
> +		cd, econet_timer.freq_hz,
> +		ECONET_MIN_DELTA, ECONET_MAX_DELTA);
> +
> +	return 0;
> +}
> +
> +static u64 notrace sched_clock_read(void)
> +{
> +	/* Always read from clock zero no matter the CPU */
> +	return (u64)ioread32(reg_count(0));
> +}
> +
> +/* Init */
> +
> +static void __init cevt_dev_init(uint cpu)
> +{
> +	iowrite32(0, reg_count(cpu));
> +	iowrite32(U32_MAX, reg_compare(cpu));
> +}
> +
> +static int __init cevt_init(struct device_node *np)
> +{
> +	int i, irq, ret;
> +
> +	irq = irq_of_parse_and_map(np, 0);
> +	if (irq <= 0) {
> +		pr_err("%pOFn: irq_of_parse_and_map failed", np);
> +		return -EINVAL;
> +	}
> +
> +	ret = request_percpu_irq(irq, cevt_interrupt, np->name, &econet_timer_pcpu);
> +
> +	if (ret < 0) {
> +		pr_err("%pOFn: IRQ %d setup failed (%d)\n", np, irq, ret);
> +		goto err_unmap_irq;
> +	}
> +
> +	for_each_possible_cpu(i) {
> +		struct clock_event_device *cd = &per_cpu(econet_timer_pcpu, i);
> +
> +		cd->rating		= 310,
> +		cd->features		= CLOCK_EVT_FEAT_ONESHOT |
> +					  CLOCK_EVT_FEAT_C3STOP |
> +					  CLOCK_EVT_FEAT_PERCPU;
> +		cd->set_next_event	= cevt_set_next_event;
> +		cd->irq			= irq;
> +		cd->cpumask		= cpumask_of(i);
> +		cd->name		= np->name;
> +
> +		cevt_dev_init(i);
> +	}
> +
> +	cpuhp_setup_state(CPUHP_AP_MIPS_GIC_TIMER_STARTING,
> +			  "clockevents/en75/timer:starting",
> +			  cevt_init_cpu, NULL);

cpuhp_setup_state(CPUHP_AP_ONLINE_DYN, ... ) ?

> +	return 0;
> +
> +err_unmap_irq:
> +	irq_dispose_mapping(irq);
> +	return ret;
> +}
> +
> +static int __init timer_init(struct device_node *np)
> +{
> +	int num_blocks = DIV_ROUND_UP(num_possible_cpus(), 2);
> +	struct clk *clk;
> +	int ret;
> +
> +	clk = of_clk_get(np, 0);
> +	if (IS_ERR(clk)) {
> +		pr_err("%pOFn: Failed to get CPU clock from DT %ld\n", np, PTR_ERR(clk));
> +		return PTR_ERR(clk);
> +	}
> +
> +	econet_timer.freq_hz = clk_get_rate(clk);
> +
> +	for (int i = 0; i < num_blocks; i++) {
> +		econet_timer.membase[i] = of_iomap(np, i);
> +		if (!econet_timer.membase[i]) {
> +			pr_err("%pOFn: failed to map register [%d]\n", np, i);
> +			return -ENXIO;
> +		}
> +	}
> +
> +	/* For clocksource purposes always read clock zero, whatever the CPU */
> +	ret = clocksource_mmio_init(reg_count(0), np->name,
> +				    econet_timer.freq_hz, 301, ECONET_BITS,
> +				    clocksource_mmio_readl_up);
> +	if (ret) {
> +		pr_err("%pOFn: clocksource_mmio_init failed: %d", np, ret);
> +		return ret;
> +	}
> +
> +	ret = cevt_init(np);
> +	if (ret < 0)
> +		return ret;
> +
> +	sched_clock_register(sched_clock_read, ECONET_BITS,
> +			     econet_timer.freq_hz);
> +
> +	pr_info("%pOFn: using %u.%03u MHz high precision timer\n", np,
> +		econet_timer.freq_hz / 1000000,
> +		(econet_timer.freq_hz / 1000) % 1000);
> +
> +	return 0;
> +}
> +
> +TIMER_OF_DECLARE(econet_timer_hpt, "econet,en751221-timer", timer_init);
> -- 
> 2.39.5
> 

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Re: [PATCH v4 2/7] clocksource/drivers: Add EcoNet Timer HPT driver

[Caleb James DeLisle]

On 05/05/2025 18:36, Daniel Lezcano wrote:
> On Wed, Apr 30, 2025 at 01:34:28PM +0000, Caleb James DeLisle wrote:
>> Introduce a clocksource driver for the so-called high-precision timer (HPT)
>> in the EcoNet EN751221 MIPS SoC.
> As a new driver, please document the timer (up - down ?, SPI/PPI, etc
> ...) that will help to understand the code more easily, especially the
> reg_* functions (purposes?).


Sure thing, I can elaborate the comment in the header of
timer-econet-en751221.c. Let me know if you'd like it described
somewhere else as well, such as the help of config ECONET_EN751221_TIMER.


>
>> Signed-off-by: Caleb James DeLisle <cjd@cjdns.fr>
>> ---
>>   drivers/clocksource/Kconfig                 |   8 +
>>   drivers/clocksource/Makefile                |   1 +
>>   drivers/clocksource/timer-econet-en751221.c | 216 ++++++++++++++++++++
>>   3 files changed, 225 insertions(+)
>>   create mode 100644 drivers/clocksource/timer-econet-en751221.c
>>
>> diff --git a/drivers/clocksource/Kconfig b/drivers/clocksource/Kconfig
>> index 487c85259967..976afb0b2312 100644
>> --- a/drivers/clocksource/Kconfig
>> +++ b/drivers/clocksource/Kconfig
>> @@ -73,6 +73,14 @@ config DW_APB_TIMER_OF
>>   	select DW_APB_TIMER
>>   	select TIMER_OF
>>   
>> +config ECONET_EN751221_TIMER
>> +	bool "EcoNet EN751221 High Precision Timer" if COMPILE_TEST
>> +	depends on HAS_IOMEM
>> +	select CLKSRC_MMIO
>> +	select TIMER_OF
>> +	help
>> +	  Support for CPU timer found on EcoNet MIPS based SoCs.
>> +
>>   config FTTMR010_TIMER
>>   	bool "Faraday Technology timer driver" if COMPILE_TEST
>>   	depends on HAS_IOMEM
>> diff --git a/drivers/clocksource/Makefile b/drivers/clocksource/Makefile
>> index 43ef16a4efa6..d2998601eda5 100644
>> --- a/drivers/clocksource/Makefile
>> +++ b/drivers/clocksource/Makefile
>> @@ -17,6 +17,7 @@ obj-$(CONFIG_CLKBLD_I8253)	+= i8253.o
>>   obj-$(CONFIG_CLKSRC_MMIO)	+= mmio.o
>>   obj-$(CONFIG_DAVINCI_TIMER)	+= timer-davinci.o
>>   obj-$(CONFIG_DIGICOLOR_TIMER)	+= timer-digicolor.o
>> +obj-$(CONFIG_ECONET_EN751221_TIMER)	+= timer-econet-en751221.o
>>   obj-$(CONFIG_OMAP_DM_TIMER)	+= timer-ti-dm.o
>>   obj-$(CONFIG_OMAP_DM_SYSTIMER)	+= timer-ti-dm-systimer.o
>>   obj-$(CONFIG_DW_APB_TIMER)	+= dw_apb_timer.o
>> diff --git a/drivers/clocksource/timer-econet-en751221.c b/drivers/clocksource/timer-econet-en751221.c
>> new file mode 100644
>> index 000000000000..9cfeead09377
>> --- /dev/null
>> +++ b/drivers/clocksource/timer-econet-en751221.c
>> @@ -0,0 +1,216 @@
>> +// SPDX-License-Identifier: GPL-2.0
>> +/*
>> + * Timer present on EcoNet EN75xx MIPS based SoCs.
>> + *
>> + * Copyright (C) 2025 by Caleb James DeLisle <cjd@cjdns.fr>
>> + */
>> +
>> +#include <linux/io.h>
>> +#include <linux/cpumask.h>
>> +#include <linux/interrupt.h>
>> +#include <linux/clockchips.h>
>> +#include <linux/sched_clock.h>
>> +#include <linux/of.h>
>> +#include <linux/of_irq.h>
>> +#include <linux/of_address.h>
>> +#include <linux/cpuhotplug.h>
>> +#include <linux/clk.h>
>> +
>> +#define ECONET_BITS			32
>> +#define ECONET_MIN_DELTA		0x00001000
>> +#define ECONET_MAX_DELTA		GENMASK(ECONET_BITS - 2, 0)
>> +/* 34Kc hardware has 1 block and 1004Kc has 2. */
>> +#define ECONET_NUM_BLOCKS		DIV_ROUND_UP(NR_CPUS, 2)
>> +
>> +static struct {
>> +	void __iomem	*membase[ECONET_NUM_BLOCKS];
>> +	u32		freq_hz;
>> +} econet_timer __ro_after_init;
>> +
>> +static DEFINE_PER_CPU(struct clock_event_device, econet_timer_pcpu);
>> +
>> +/* Each memory block has 2 timers, the order of registers is:
>> + * CTL, CMR0, CNT0, CMR1, CNT1
>> + */
>> +static inline void __iomem *reg_ctl(u32 timer_n)
>> +{
>> +	return econet_timer.membase[timer_n >> 1];
>> +}
>> +
>> +static inline void __iomem *reg_compare(u32 timer_n)
>> +{
>> +	return econet_timer.membase[timer_n >> 1] + (timer_n & 1) * 0x08 + 0x04;
>> +}
>> +
>> +static inline void __iomem *reg_count(u32 timer_n)
>> +{
>> +	return econet_timer.membase[timer_n >> 1] + (timer_n & 1) * 0x08 + 0x08;
>> +}
>> +
>> +static inline u32 ctl_bit_enabled(u32 timer_n)
>> +{
>> +	return 1U << (timer_n & 1);
>> +}
>> +
>> +static inline u32 ctl_bit_pending(u32 timer_n)
>> +{
>> +	return 1U << ((timer_n & 1) + 16);
>> +}
>> +
>> +static bool cevt_is_pending(int cpu_id)
>> +{
>> +	return ioread32(reg_ctl(cpu_id)) & ctl_bit_pending(cpu_id);
>> +}
>> +
>> +static irqreturn_t cevt_interrupt(int irq, void *dev_id)
>> +{
>> +	struct clock_event_device *dev = this_cpu_ptr(&econet_timer_pcpu);
>> +	int cpu = cpumask_first(dev->cpumask);
>> +
>> +	if (!cevt_is_pending(cpu)) {
>> +		pr_debug("%s IRQ %d on CPU %d is not pending\n", __func__, irq, cpu);
>> +		return IRQ_NONE;
>> +	}
> How this can happen ? Can this interrupt be shared ?
To my knowledge it can't, but vendor code does it and I wasn't feeling
bold enough to gamble.
> The system will account this as a spurious interrupt, the debug
> message is not needed.
Good point, will remove.
>
>> +	iowrite32(ioread32(reg_count(cpu)), reg_compare(cpu));
>> +	dev->event_handler(dev);
>> +	return IRQ_HANDLED;
>> +}
>> +
>> +static int cevt_set_next_event(ulong delta, struct clock_event_device *dev)
>> +{
>> +	u32 next;
>> +	int cpu;
>> +
>> +	cpu = cpumask_first(dev->cpumask);
>> +	next = ioread32(reg_count(cpu)) + delta;
>> +	iowrite32(next, reg_compare(cpu));
>> +
>> +	if ((s32)(next - ioread32(reg_count(cpu))) < ECONET_MIN_DELTA / 2)
>> +		return -ETIME;
>> +
>> +	return 0;
>> +}
>> +
>> +static int cevt_init_cpu(uint cpu)
>> +{
>> +	struct clock_event_device *cd = &per_cpu(econet_timer_pcpu, cpu);
>> +	u32 reg;
>> +
>> +	pr_info("%s: Setting up clockevent for CPU %d\n", cd->name, cpu);
> That is more debug information
Fair enough, will change.
>> +	reg = ioread32(reg_ctl(cpu)) | ctl_bit_enabled(cpu);
>> +	iowrite32(reg, reg_ctl(cpu));
>> +
>> +	enable_percpu_irq(cd->irq, IRQ_TYPE_NONE);
>> +
>> +	/* Do this last because it synchronously configures the timer */
>> +	clockevents_config_and_register(
>> +		cd, econet_timer.freq_hz,
>> +		ECONET_MIN_DELTA, ECONET_MAX_DELTA);
>> +
>> +	return 0;
>> +}
>> +
>> +static u64 notrace sched_clock_read(void)
>> +{
>> +	/* Always read from clock zero no matter the CPU */
>> +	return (u64)ioread32(reg_count(0));
>> +}
>> +
>> +/* Init */
>> +
>> +static void __init cevt_dev_init(uint cpu)
>> +{
>> +	iowrite32(0, reg_count(cpu));
>> +	iowrite32(U32_MAX, reg_compare(cpu));
>> +}
>> +
>> +static int __init cevt_init(struct device_node *np)
>> +{
>> +	int i, irq, ret;
>> +
>> +	irq = irq_of_parse_and_map(np, 0);
>> +	if (irq <= 0) {
>> +		pr_err("%pOFn: irq_of_parse_and_map failed", np);
>> +		return -EINVAL;
>> +	}
>> +
>> +	ret = request_percpu_irq(irq, cevt_interrupt, np->name, &econet_timer_pcpu);
>> +
>> +	if (ret < 0) {
>> +		pr_err("%pOFn: IRQ %d setup failed (%d)\n", np, irq, ret);
>> +		goto err_unmap_irq;
>> +	}
>> +
>> +	for_each_possible_cpu(i) {
>> +		struct clock_event_device *cd = &per_cpu(econet_timer_pcpu, i);
>> +
>> +		cd->rating		= 310,
>> +		cd->features		= CLOCK_EVT_FEAT_ONESHOT |
>> +					  CLOCK_EVT_FEAT_C3STOP |
>> +					  CLOCK_EVT_FEAT_PERCPU;
>> +		cd->set_next_event	= cevt_set_next_event;
>> +		cd->irq			= irq;
>> +		cd->cpumask		= cpumask_of(i);
>> +		cd->name		= np->name;
>> +
>> +		cevt_dev_init(i);
>> +	}
>> +
>> +	cpuhp_setup_state(CPUHP_AP_MIPS_GIC_TIMER_STARTING,
>> +			  "clockevents/en75/timer:starting",
>> +			  cevt_init_cpu, NULL);
> cpuhp_setup_state(CPUHP_AP_ONLINE_DYN, ... ) ?

I see that Ingenic does this. This is the only timer so until it's up,
sleeping causes a hang. If sleeping is prior to CPUHP_AP_ONLINE_DYN is
considered a bug then this should be okay, but I'm not informed enough
to say whether that is the case so I'll follow your guidance here.


Thanks,

Caleb


>
>> +	return 0;
>> +
>> +err_unmap_irq:
>> +	irq_dispose_mapping(irq);
>> +	return ret;
>> +}
>> +
>> +static int __init timer_init(struct device_node *np)
>> +{
>> +	int num_blocks = DIV_ROUND_UP(num_possible_cpus(), 2);
>> +	struct clk *clk;
>> +	int ret;
>> +
>> +	clk = of_clk_get(np, 0);
>> +	if (IS_ERR(clk)) {
>> +		pr_err("%pOFn: Failed to get CPU clock from DT %ld\n", np, PTR_ERR(clk));
>> +		return PTR_ERR(clk);
>> +	}
>> +
>> +	econet_timer.freq_hz = clk_get_rate(clk);
>> +
>> +	for (int i = 0; i < num_blocks; i++) {
>> +		econet_timer.membase[i] = of_iomap(np, i);
>> +		if (!econet_timer.membase[i]) {
>> +			pr_err("%pOFn: failed to map register [%d]\n", np, i);
>> +			return -ENXIO;
>> +		}
>> +	}
>> +
>> +	/* For clocksource purposes always read clock zero, whatever the CPU */
>> +	ret = clocksource_mmio_init(reg_count(0), np->name,
>> +				    econet_timer.freq_hz, 301, ECONET_BITS,
>> +				    clocksource_mmio_readl_up);
>> +	if (ret) {
>> +		pr_err("%pOFn: clocksource_mmio_init failed: %d", np, ret);
>> +		return ret;
>> +	}
>> +
>> +	ret = cevt_init(np);
>> +	if (ret < 0)
>> +		return ret;
>> +
>> +	sched_clock_register(sched_clock_read, ECONET_BITS,
>> +			     econet_timer.freq_hz);
>> +
>> +	pr_info("%pOFn: using %u.%03u MHz high precision timer\n", np,
>> +		econet_timer.freq_hz / 1000000,
>> +		(econet_timer.freq_hz / 1000) % 1000);
>> +
>> +	return 0;
>> +}
>> +
>> +TIMER_OF_DECLARE(econet_timer_hpt, "econet,en751221-timer", timer_init);
>> -- 
>> 2.39.5
>>

Re: [PATCH v4 2/7] clocksource/drivers: Add EcoNet Timer HPT driver

[Daniel Lezcano]

On 05/05/2025 20:09, Caleb James DeLisle wrote:
> 
> On 05/05/2025 18:36, Daniel Lezcano wrote:
>> On Wed, Apr 30, 2025 at 01:34:28PM +0000, Caleb James DeLisle wrote:
>>> Introduce a clocksource driver for the so-called high-precision timer 
>>> (HPT)
>>> in the EcoNet EN751221 MIPS SoC.
>> As a new driver, please document the timer (up - down ?, SPI/PPI, etc
>> ...) that will help to understand the code more easily, especially the
>> reg_* functions (purposes?).
> 
> 
> Sure thing, I can elaborate the comment in the header of
> timer-econet-en751221.c. Let me know if you'd like it described
> somewhere else as well, such as the help of config ECONET_EN751221_TIMER.

It is ok in the changelog, so it is possible to get the description when 
looking for the patch introducing the new timer.

[ ... ]

>>> +
>>> +    cpuhp_setup_state(CPUHP_AP_MIPS_GIC_TIMER_STARTING,
>>> +              "clockevents/en75/timer:starting",
>>> +              cevt_init_cpu, NULL);
>> cpuhp_setup_state(CPUHP_AP_ONLINE_DYN, ... ) ?
> 
> I see that Ingenic does this. This is the only timer so until it's up,
> sleeping causes a hang. If sleeping is prior to CPUHP_AP_ONLINE_DYN is
> considered a bug then this should be okay, but I'm not informed enough
> to say whether that is the case so I'll follow your guidance here.

Hmm, hard to say without the platform. May be just give a try with 
CPUHP_AP_ONLINE_DYN to check if it works otherwise stick on 
CPUHP_AP_MIPS_GIC_TIMER_STARTING as it is already defined ?

[ ... ]


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Re: [PATCH v4 2/7] clocksource/drivers: Add EcoNet Timer HPT driver

[Caleb James DeLisle]

On 06/05/2025 10:54, Daniel Lezcano wrote:
> On 05/05/2025 20:09, Caleb James DeLisle wrote:
>>
>> On 05/05/2025 18:36, Daniel Lezcano wrote:
>>> On Wed, Apr 30, 2025 at 01:34:28PM +0000, Caleb James DeLisle wrote:
>>>> Introduce a clocksource driver for the so-called high-precision 
>>>> timer (HPT)
>>>> in the EcoNet EN751221 MIPS SoC.
>>> As a new driver, please document the timer (up - down ?, SPI/PPI, etc
>>> ...) that will help to understand the code more easily, especially the
>>> reg_* functions (purposes?).
>>
>>
>> Sure thing, I can elaborate the comment in the header of
>> timer-econet-en751221.c. Let me know if you'd like it described
>> somewhere else as well, such as the help of config 
>> ECONET_EN751221_TIMER.
>
> It is ok in the changelog, so it is possible to get the description 
> when looking for the patch introducing the new timer.


Sounds good.


>
> [ ... ]
>
>>>> +
>>>> +    cpuhp_setup_state(CPUHP_AP_MIPS_GIC_TIMER_STARTING,
>>>> +              "clockevents/en75/timer:starting",
>>>> +              cevt_init_cpu, NULL);
>>> cpuhp_setup_state(CPUHP_AP_ONLINE_DYN, ... ) ?
>>
>> I see that Ingenic does this. This is the only timer so until it's up,
>> sleeping causes a hang. If sleeping is prior to CPUHP_AP_ONLINE_DYN is
>> considered a bug then this should be okay, but I'm not informed enough
>> to say whether that is the case so I'll follow your guidance here.
>
> Hmm, hard to say without the platform. May be just give a try with 
> CPUHP_AP_ONLINE_DYN to check if it works otherwise stick on 
> CPUHP_AP_MIPS_GIC_TIMER_STARTING as it is already defined ?


I need a little time for this because I only got SMP on this processor

some time ago in a PoC so I'll need to put that back together in order

to validate the change.


Thanks,

Caleb


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