On 2022-02-16 13:28, Shawn Guo wrote:
Qualcomm SoCs based on the RPM architecture have a MSM Power Manager
(MPM)
in always-on domain. In addition to managing resources during sleep,
the
hardware also has an interrupt controller that monitors the interrupts
when the system is asleep, wakes up the APSS when one of these
interrupts
occur and replays it to GIC after it becomes operational.
It adds an irqchip driver for this interrupt controller, and here are
some notes about it.
- For given SoC, a fixed number of MPM pins are supported, e.g. 96 pins
on QCM2290. Each of these MPM pins can be either a MPM_GIC pin or
a MPM_GPIO pin. The mapping between MPM_GIC pin and GIC interrupt
is defined by SoC, as well as the mapping between MPM_GPIO pin and
GPIO number. The former mapping is retrieved from device tree, while
the latter is defined in TLMM pinctrl driver.
- Different from vendor driver that handles MPM_GIC and MPM_GPIO pin
with separate irq_domain (and irq_chip), it handles both with a
single
irq_domain, and distinguishes them by checking parent IRQ, since only
MPM_GIC pin has a parent GIC SPI number.
I don't think we need this paragraph. Out of tree code is pretty much
irrelevant.
- When SoC gets awake from sleep mode, the driver will receive an
interrupt from RPM, so that it can replay interrupt for particular
polarity.
Signed-off-by: Shawn Guo <shawn.guo@xxxxxxxxxx>
---
drivers/irqchip/Kconfig | 8 +
drivers/irqchip/Makefile | 1 +
drivers/irqchip/qcom-mpm.c | 440 +++++++++++++++++++++++++++++++++++++
3 files changed, 449 insertions(+)
create mode 100644 drivers/irqchip/qcom-mpm.c
diff --git a/drivers/irqchip/Kconfig b/drivers/irqchip/Kconfig
index 7038957f4a77..680d2fcf2686 100644
--- a/drivers/irqchip/Kconfig
+++ b/drivers/irqchip/Kconfig
@@ -430,6 +430,14 @@ config QCOM_PDC
Power Domain Controller driver to manage and configure wakeup
IRQs for Qualcomm Technologies Inc (QTI) mobile chips.
+config QCOM_MPM
+ tristate "QCOM MPM"
+ depends on ARCH_QCOM
+ select IRQ_DOMAIN_HIERARCHY
+ help
+ MSM Power Manager driver to manage and configure wakeup
+ IRQs for Qualcomm Technologies Inc (QTI) mobile chips.
+
config CSKY_MPINTC
bool
depends on CSKY
diff --git a/drivers/irqchip/Makefile b/drivers/irqchip/Makefile
index c1f611cbfbf8..0e2e10467e28 100644
--- a/drivers/irqchip/Makefile
+++ b/drivers/irqchip/Makefile
@@ -94,6 +94,7 @@ obj-$(CONFIG_MESON_IRQ_GPIO) += irq-meson-gpio.o
obj-$(CONFIG_GOLDFISH_PIC) += irq-goldfish-pic.o
obj-$(CONFIG_NDS32) += irq-ativic32.o
obj-$(CONFIG_QCOM_PDC) += qcom-pdc.o
+obj-$(CONFIG_QCOM_MPM) += qcom-mpm.o
obj-$(CONFIG_CSKY_MPINTC) += irq-csky-mpintc.o
obj-$(CONFIG_CSKY_APB_INTC) += irq-csky-apb-intc.o
obj-$(CONFIG_RISCV_INTC) += irq-riscv-intc.o
diff --git a/drivers/irqchip/qcom-mpm.c b/drivers/irqchip/qcom-mpm.c
new file mode 100644
index 000000000000..06c2ed14635f
--- /dev/null
+++ b/drivers/irqchip/qcom-mpm.c
@@ -0,0 +1,440 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * Copyright (c) 2021, Linaro Limited
+ * Copyright (c) 2010-2020, The Linux Foundation. All rights reserved.
+ */
+
+#include <linux/cpu_pm.h>
+#include <linux/delay.h>
+#include <linux/err.h>
+#include <linux/init.h>
+#include <linux/interrupt.h>
+#include <linux/io.h>
+#include <linux/irqchip.h>
+#include <linux/irqchip/arm-gic-v3.h>
+#include <linux/irqdomain.h>
+#include <linux/mailbox_client.h>
+#include <linux/module.h>
+#include <linux/of.h>
+#include <linux/of_device.h>
+#include <linux/platform_device.h>
+#include <linux/slab.h>
+#include <linux/soc/qcom/irq.h>
+#include <linux/spinlock.h>
+
+/*
+ * This is the driver for Qualcomm MPM (MSM Power Manager) interrupt
controller,
+ * which is commonly found on Qualcomm SoCs built on the RPM
architecture.
+ * Sitting in always-on domain, MPM monitors the wakeup interrupts
when SoC is
+ * asleep, and wakes up the AP when one of those interrupts occurs.
This driver
+ * doesn't directly access physical MPM registers though. Instead,
the access
+ * is bridged via a piece of internal memory (SRAM) that is accessible
to both
+ * AP and RPM. This piece of memory is called 'vMPM' in the driver.
+ *
+ * When SoC is awake, the vMPM is owned by AP and the register setup
by this
+ * driver all happens on vMPM. When AP is about to get power
collapsed, the
+ * driver sends a mailbox notification to RPM, which will take over
the vMPM
+ * ownership and dump vMPM into physical MPM registers. On wakeup, AP
is woken
+ * up by a MPM pin/interrupt, and RPM will copy STATUS registers into
vMPM.
+ * Then AP start owning vMPM again.
+ *
+ * vMPM register map:
+ *
+ * 31 0
+ * +--------------------------------+
+ * | TIMER0 | 0x00
+ * +--------------------------------+
+ * | TIMER1 | 0x04
+ * +--------------------------------+
+ * | ENABLE0 | 0x08
+ * +--------------------------------+
+ * | ... | ...
+ * +--------------------------------+
+ * | ENABLEn |
+ * +--------------------------------+
+ * | FALLING_EDGE0 |
+ * +--------------------------------+
+ * | ... |
+ * +--------------------------------+
+ * | STATUSn |
+ * +--------------------------------+
+ *
+ * n = DIV_ROUND_UP(pin_cnt, 32)
+ *
+ */
+
+#define MPM_REG_ENABLE 0
+#define MPM_REG_FALLING_EDGE 1
+#define MPM_REG_RISING_EDGE 2
+#define MPM_REG_POLARITY 3
+#define MPM_REG_STATUS 4
+
+#define MPM_NO_PARENT_IRQ ~0UL
+
+/* MPM pin map to GIC hwirq */
+struct mpm_gic_map {
+ int pin;
+ irq_hw_number_t hwirq;
+};
+
+struct qcom_mpm_priv {
+ void __iomem *base;
+ raw_spinlock_t lock;
+ struct mbox_client mbox_client;
+ struct mbox_chan *mbox_chan;
+ struct mpm_gic_map *maps;
+ unsigned int map_cnt;
+ unsigned int reg_stride;
+ struct irq_domain *domain;
+ struct notifier_block pm_nb;
+};
+
+static u32 qcom_mpm_read(struct qcom_mpm_priv *priv, unsigned int reg,
+ unsigned int index)
+{
+ unsigned int offset = (reg * priv->reg_stride + index + 2) * 4;
+
+ return readl_relaxed(priv->base + offset);
+}
+
+static void qcom_mpm_write(struct qcom_mpm_priv *priv, unsigned int
reg,
+ unsigned int index, u32 val)
+{
+ unsigned int offset = (reg * priv->reg_stride + index + 2) * 4;
+
+ writel_relaxed(val, priv->base + offset);
+
+ /* Ensure the write is completed */
+ wmb();
+}
+
+static void qcom_mpm_enable_irq(struct irq_data *d, bool en)
+{
+ struct qcom_mpm_priv *priv = d->chip_data;
+ int pin = d->hwirq;
+ unsigned int index = pin / 32;
+ unsigned int shift = pin % 32;
+ unsigned long flags;
+ u32 val;
+
+ raw_spin_lock_irqsave(&priv->lock, flags);
+
+ val = qcom_mpm_read(priv, MPM_REG_ENABLE, index);
+ if (en)
+ val |= BIT(shift);
+ else
+ val &= ~BIT(shift);
+ qcom_mpm_write(priv, MPM_REG_ENABLE, index, val);
+
+ raw_spin_unlock_irqrestore(&priv->lock, flags);
+}
+
+static void qcom_mpm_mask(struct irq_data *d)
+{
+ qcom_mpm_enable_irq(d, false);
+
+ if (d->parent_data)
+ irq_chip_mask_parent(d);
+}
+
+static void qcom_mpm_unmask(struct irq_data *d)
+{
+ qcom_mpm_enable_irq(d, true);
+
+ if (d->parent_data)
+ irq_chip_unmask_parent(d);
+}
+
+static void mpm_set_type(struct qcom_mpm_priv *priv, bool set,
unsigned int reg,
+ unsigned int index, unsigned int shift)
+{
+ unsigned long flags;
+ u32 val;
+
+ raw_spin_lock_irqsave(&priv->lock, flags);
+
+ val = qcom_mpm_read(priv, reg, index);
+ if (set)
+ val |= BIT(shift);
+ else
+ val &= ~BIT(shift);
+ qcom_mpm_write(priv, reg, index, val);
+
+ raw_spin_unlock_irqrestore(&priv->lock, flags);
+}
+
+static int qcom_mpm_set_type(struct irq_data *d, unsigned int type)
+{
+ struct qcom_mpm_priv *priv = d->chip_data;
+ int pin = d->hwirq;
+ unsigned int index = pin / 32;
+ unsigned int shift = pin % 32;
+
+ switch (type & IRQ_TYPE_SENSE_MASK) {
+ case IRQ_TYPE_EDGE_RISING:
+ mpm_set_type(priv, !!(type & IRQ_TYPE_EDGE_RISING),
+ MPM_REG_RISING_EDGE, index, shift);
+ break;
+ case IRQ_TYPE_EDGE_FALLING:
+ mpm_set_type(priv, !!(type & IRQ_TYPE_EDGE_FALLING),
+ MPM_REG_FALLING_EDGE, index, shift);
+ break;
+ case IRQ_TYPE_LEVEL_HIGH:
+ mpm_set_type(priv, !!(type & IRQ_TYPE_LEVEL_HIGH),
+ MPM_REG_POLARITY, index, shift);
+ break;
+ }
+
+ if (!d->parent_data)
+ return 0;
+
+ if (type & IRQ_TYPE_EDGE_BOTH)
+ type = IRQ_TYPE_EDGE_RISING;
+
+ if (type & IRQ_TYPE_LEVEL_MASK)
+ type = IRQ_TYPE_LEVEL_HIGH;
+
+ return irq_chip_set_type_parent(d, type);
+}
+
+static struct irq_chip qcom_mpm_chip = {
+ .name = "mpm",
+ .irq_eoi = irq_chip_eoi_parent,
+ .irq_mask = qcom_mpm_mask,
+ .irq_unmask = qcom_mpm_unmask,
+ .irq_retrigger = irq_chip_retrigger_hierarchy,
+ .irq_set_type = qcom_mpm_set_type,
+ .irq_set_affinity = irq_chip_set_affinity_parent,
+ .flags = IRQCHIP_MASK_ON_SUSPEND |
+ IRQCHIP_SKIP_SET_WAKE,
+};
+
+static irq_hw_number_t get_parent_hwirq(struct qcom_mpm_priv *priv,
int pin)
+{
+ const struct mpm_gic_map *maps = priv->maps;
+ int i;
+
+ for (i = 0; i < priv->map_cnt; i++) {
+ if (maps[i].pin == pin)
+ return maps[i].hwirq;
+ }
+
+ return MPM_NO_PARENT_IRQ;
I'd rather you change this helper to return a pointer to the mapping
data,
and NULL on failure. This will avoid inventing magic values which may
or may not clash with an interrupt number in the future.
+}
+
+static int qcom_mpm_alloc(struct irq_domain *domain, unsigned int
virq,
+ unsigned int nr_irqs, void *data)
+{
+ struct qcom_mpm_priv *priv = domain->host_data;
+ struct irq_fwspec *fwspec = data;
+ struct irq_fwspec parent_fwspec;
+ irq_hw_number_t parent_hwirq;
Isn't this the pin number? If so, I'd rather you call it that.
+ irq_hw_number_t hwirq;
+ unsigned int type;
+ int ret;
+
+ ret = irq_domain_translate_twocell(domain, fwspec, &hwirq, &type);
+ if (ret)
+ return ret;
+
+ ret = irq_domain_set_hwirq_and_chip(domain, virq, hwirq,
+ &qcom_mpm_chip, priv);
+ if (ret)
+ return ret;
+
+ parent_hwirq = get_parent_hwirq(priv, hwirq);
+ if (parent_hwirq == MPM_NO_PARENT_IRQ)
+ return irq_domain_disconnect_hierarchy(domain->parent, virq);
+
+ if (type & IRQ_TYPE_EDGE_BOTH)
+ type = IRQ_TYPE_EDGE_RISING;
+
+ if (type & IRQ_TYPE_LEVEL_MASK)
+ type = IRQ_TYPE_LEVEL_HIGH;
+
+ parent_fwspec.fwnode = domain->parent->fwnode;
+ parent_fwspec.param_count = 3;
+ parent_fwspec.param[0] = 0;
+ parent_fwspec.param[1] = parent_hwirq;
+ parent_fwspec.param[2] = type;
+
+ return irq_domain_alloc_irqs_parent(domain, virq, nr_irqs,
+ &parent_fwspec);
+}
+
+static const struct irq_domain_ops qcom_mpm_ops = {
+ .alloc = qcom_mpm_alloc,
+ .free = irq_domain_free_irqs_common,
+ .translate = irq_domain_translate_twocell,
+};
+
+/* Triggered by RPM when system resumes from deep sleep */
+static irqreturn_t qcom_mpm_handler(int irq, void *dev_id)
+{
+ struct qcom_mpm_priv *priv = dev_id;
+ unsigned long enable, pending;
+ int i, j;
+
+ for (i = 0; i < priv->reg_stride; i++) {
+ enable = qcom_mpm_read(priv, MPM_REG_ENABLE, i);
+ pending = qcom_mpm_read(priv, MPM_REG_STATUS, i);
+ pending &= enable;
Is it safe to run all this without any form of locking? From what I can
tell, other CPUs could enable and disable interrupts in parallel to
this.
+ for_each_set_bit(j, &pending, 32) {
+ unsigned int pin = 32 * i + j;
+ struct irq_desc *desc = irq_resolve_mapping(priv->domain, pin);
+ struct irq_data *d = &desc->irq_data;
+
+ if (!irqd_is_level_type(d))
+ irq_set_irqchip_state(d->irq,
+ IRQCHIP_STATE_PENDING, true);
+
+ }
+ }
+
+ return IRQ_HANDLED;
This can obviously be reached without any interrupt being actually
handled.
+}
+
+static int qcom_mpm_enter_sleep(struct qcom_mpm_priv *priv)
+{
+ int i, ret;
+
+ for (i = 0; i < priv->reg_stride; i++)
+ qcom_mpm_write(priv, MPM_REG_STATUS, i, 0);
+
+ /* Notify RPM to write vMPM into HW */
+ ret = mbox_send_message(priv->mbox_chan, NULL);
+ if (ret < 0)
+ return ret;
+
+ return 0;
+}
+
+static int qcom_mpm_cpu_pm_callback(struct notifier_block *nb,
+ unsigned long action, void *data)
+{
+ struct qcom_mpm_priv *priv = container_of(nb, struct qcom_mpm_priv,
+ pm_nb);
+ int ret = NOTIFY_OK;
+
+ switch (action) {
+ case CPU_CLUSTER_PM_ENTER:
+ if (qcom_mpm_enter_sleep(priv))
+ ret = NOTIFY_BAD;
+ break;
+ default:
+ return NOTIFY_DONE;
ret = NOTIFY_DONE; ?
+ }
+
+ return ret;
+}
+
+static int qcom_mpm_init(struct device_node *np, struct device_node
*parent)
+{
+ struct platform_device *pdev = of_find_device_by_node(np);
+ struct device *dev = &pdev->dev;
+ struct irq_domain *parent_domain;
+ struct qcom_mpm_priv *priv;
+ unsigned int pin_cnt;
+ int i, irq;
+ int ret;
+
+ priv = devm_kzalloc(dev, sizeof(*priv), GFP_KERNEL);
+ if (!priv)
+ return -ENOMEM;
+
+ ret = of_property_read_u32(np, "qcom,mpm-pin-count", &pin_cnt);
+ if (ret) {
+ dev_err(dev, "failed to read qcom,mpm-pin-count: %d\n", ret);
+ return ret;
+ }
+
+ priv->reg_stride = DIV_ROUND_UP(pin_cnt, 32);
+
+ ret = of_property_count_u32_elems(np, "qcom,mpm-pin-map");
+ if (ret < 0) {
+ dev_err(dev, "failed to read qcom,mpm-pin-map: %d\n", ret);
+ return ret;
+ }
+
+ if (ret % 2) {
+ dev_err(dev, "invalid qcom,mpm-pin-map\n");
+ return -EINVAL;
+ }
+
+ priv->map_cnt = ret / 2;
+ priv->maps = devm_kcalloc(dev, priv->map_cnt, sizeof(*priv->maps),
+ GFP_KERNEL);
+ if (!priv->maps)
+ return -ENOMEM;
+
+ for (i = 0; i < priv->map_cnt; i++) {
+ of_property_read_u32_index(np, "qcom,mpm-pin-map", i * 2,
+ &priv->maps[i].pin);
+ of_property_read_u32_index(np, "qcom,mpm-pin-map", i * 2 + 1,
+ (u32 *) &priv->maps[i].hwirq);
+ }
+
+ raw_spin_lock_init(&priv->lock);
+
+ priv->base = devm_platform_ioremap_resource(pdev, 0);
+ if (!priv->base)
+ return PTR_ERR(priv->base);
+
+ irq = platform_get_irq(pdev, 0);
+ if (irq < 0)
+ return irq;
+
+ priv->mbox_client.dev = dev;
+ priv->mbox_chan = mbox_request_channel(&priv->mbox_client, 0);
+ if (IS_ERR(priv->mbox_chan)) {
+ ret = PTR_ERR(priv->mbox_chan);
+ dev_err(dev, "failed to acquire IPC channel: %d\n", ret);
+ return ret;
+ }
+
+ parent_domain = irq_find_host(parent);
+ if (!parent_domain) {
+ dev_err(dev, "failed to find MPM parent domain\n");
+ ret = -ENXIO;
+ goto free_mbox;
+ }
+
+ priv->domain = irq_domain_create_hierarchy(parent_domain,
+ IRQ_DOMAIN_FLAG_QCOM_MPM_WAKEUP, pin_cnt,
+ of_node_to_fwnode(np), &qcom_mpm_ops, priv);
+ if (!priv->domain) {
+ dev_err(dev, "failed to create MPM domain\n");
+ ret = -ENOMEM;
+ goto free_mbox;
+ }
+
+ irq_domain_update_bus_token(priv->domain, DOMAIN_BUS_WAKEUP);
+
+ ret = devm_request_irq(dev, irq, qcom_mpm_handler,
+ IRQF_TRIGGER_RISING | IRQF_NO_SUSPEND,
Can you just get the trigger type as exposed by the device tree?
In general, you shouldn't have to specify it at all.
+ "qcom_mpm", priv);
+ if (ret) {
+ dev_err(dev, "failed to request irq: %d\n", ret);
+ goto remove_domain;
+ }
+
+ priv->pm_nb.notifier_call = qcom_mpm_cpu_pm_callback;
+ cpu_pm_register_notifier(&priv->pm_nb);
+
+ dev_set_drvdata(dev, priv);
What is the use of this? I don't see anything retrieving it...
+
+ return 0;
+
+remove_domain:
+ irq_domain_remove(priv->domain);
+free_mbox:
+ mbox_free_channel(priv->mbox_chan);
+ return ret;
+}
+
+IRQCHIP_PLATFORM_DRIVER_BEGIN(qcom_mpm)
+IRQCHIP_MATCH("qcom,mpm", qcom_mpm_init)
+IRQCHIP_PLATFORM_DRIVER_END(qcom_mpm)
+MODULE_DESCRIPTION("Qualcomm Technologies, Inc. MSM Power Manager");
+MODULE_LICENSE("GPL v2");
Other than that, this is starting to look OK. You 'only' need to
work out how to to get a last-man-standing notification in a way
that is manageable.
Thanks,
M.
--
Jazz is not dead. It just smells funny...
