Merge "soc: qcom: Implement early domain handoff driver"

5 files changed, 490 insertions, 0 deletions

diff --git a/Documentation/devicetree/bindings/platform/msm/early_domain.txt b/Documentation/devicetree/bindings/platform/msm/early_domain.txt
new file mode 100644
index 000000000000..c213fb81dfa0
--- /dev/null
+++ b/Documentation/devicetree/bindings/platform/msm/early_domain.txt
@@ -0,0 +1,29 @@
+Early domain core driver.
+
+Early domain in bootloader run multimedia services like display,
+camera, audio by reserving cpu(s) and some memory in parallel with
+kernel.
+
+These services may need to stop when they decide. Early domain
+driver in kernel communicates with early services through a shared
+memory block. This block is reserved during kernel boot.
+
+Early services running in bootloader update their status in the
+shared memory block. Multimedia drivers in kernel can make use of
+apis provided by early domain core driver to get the status of early
+services and free reserved memory resource to system
+when the early services end.
+
+Required properties
+- compatible : 	should be "qcom,early_domain"
+- status     : 	should be "disabled" by default.
+		status should be made "ok" only
+		if earlydomain is active by
+		bootloaders.
+
+Example:
+	early_domain: early_domain  {
+			compatible = "qcom,early_domain";
+			status = "disabled";
+	};
+
diff --git a/drivers/soc/qcom/Kconfig b/drivers/soc/qcom/Kconfig
index 62b7d12629e4..d2ac10ad4c4c 100644
--- a/drivers/soc/qcom/Kconfig
+++ b/drivers/soc/qcom/Kconfig
@@ -392,6 +392,9 @@ config QCOM_SCM_QCPE
        bool "Para-Virtualized Secure Channel Manager (SCM) support over QCPE"
        default n
 
+config QCOM_EARLY_DOMAIN
+	bool "Support for handoff of early domain services running in bootloader"
+
 menuconfig QCOM_SCM_XPU
 	bool "Qualcomm XPU configuration driver"
 	depends on QCOM_SCM
diff --git a/drivers/soc/qcom/Makefile b/drivers/soc/qcom/Makefile
index 7dff5d3b8d72..c8933e97901d 100644
--- a/drivers/soc/qcom/Makefile
+++ b/drivers/soc/qcom/Makefile
@@ -71,6 +71,7 @@ obj-$(CONFIG_QCOM_MEMORY_DUMP_V2) += memory_dump_v2.o
 obj-$(CONFIG_QCOM_MINIDUMP) += msm_minidump.o
 obj-$(CONFIG_QCOM_DCC) += dcc.o
 obj-$(CONFIG_QCOM_WATCHDOG_V2) += watchdog_v2.o
+obj-$(CONFIG_QCOM_EARLY_DOMAIN)	+= early_dom.o
 obj-$(CONFIG_QCOM_COMMON_LOG) += common_log.o
 obj-$(CONFIG_QCOM_IRQ_HELPER) += irq-helper.o
 obj-$(CONFIG_TRACER_PKT)	+=	tracer_pkt.o
diff --git a/drivers/soc/qcom/early_dom.c b/drivers/soc/qcom/early_dom.c
new file mode 100644
index 000000000000..6731284e7ecd
--- /dev/null
+++ b/drivers/soc/qcom/early_dom.c
@@ -0,0 +1,359 @@
+/* Copyright (c) 2018, The Linux Foundation. All rights reserved.
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 and
+ * only version 2 as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ */
+
+#include <linux/module.h>
+#include <linux/kernel.h>
+#include <linux/percpu.h>
+#include <linux/of.h>
+#include <linux/of_address.h>
+#include <linux/slab.h>
+#include <linux/delay.h>
+#include <linux/cpu.h>
+#include <linux/io.h>
+#include <linux/platform_device.h>
+#include <linux/memblock.h>
+#include <linux/cpu.h>
+#include <linux/device.h>
+#include <soc/qcom/early_domain.h>
+#include <linux/string.h>
+#include <linux/bitops.h>
+#include <asm/barrier.h>
+
+static struct early_domain_core *ed_core_data;
+static bool early_domain_enabled;
+
+bool get_early_service_status(enum service_id sid)
+{
+	struct early_domain_core *domain;
+	unsigned long *status;
+
+	if (!early_domain_enabled)
+		return false;
+	domain = ed_core_data;
+	status = &domain->pdata->early_domain_status;
+	cpu_relax();
+	return test_bit(sid, status);
+}
+EXPORT_SYMBOL(get_early_service_status);
+
+static void active_early_services(void)
+{
+	enum service_id core;
+	int i;
+	bool active;
+
+	core = EARLY_DOMAIN_CORE;
+	i = (int)core;
+	while (i < NUM_SERVICES) {
+		active = get_early_service_status((enum service_id)i);
+		if (active)
+			pr_info("Early service_id:%d active\n", i);
+		i++;
+	}
+}
+
+void request_early_service_shutdown(enum service_id sid)
+{
+	struct early_domain_core *domain = ed_core_data;
+	unsigned long *request;
+
+	request = &domain->pdata->early_domain_request;
+	set_bit(sid, request);
+}
+EXPORT_SYMBOL(request_early_service_shutdown);
+
+void *get_service_shared_mem_start(enum service_id sid)
+{
+	void *service_shared_mem_start;
+	void *early_domain_shm_start;
+
+	if (!early_domain_enabled || sid < EARLY_DISPLAY || sid > NUM_SERVICES)
+		return NULL;
+
+	early_domain_shm_start = ed_core_data->pdata;
+	service_shared_mem_start = early_domain_shm_start +
+					sizeof(struct early_domain_header) +
+					(SERVICE_SHARED_MEM_SIZE * (sid - 1));
+	return service_shared_mem_start;
+}
+EXPORT_SYMBOL(get_service_shared_mem_start);
+
+static void free_reserved_lk_mem(phys_addr_t paddr, size_t size)
+{
+	unsigned long pfn_start, pfn_end, pfn_idx;
+
+	memblock_free(paddr, size);
+	pfn_start = paddr >> PAGE_SHIFT;
+	pfn_end = (paddr + size) >> PAGE_SHIFT;
+	for (pfn_idx = pfn_start; pfn_idx < pfn_end; pfn_idx++)
+		free_reserved_page(pfn_to_page(pfn_idx));
+}
+
+static void early_domain_work(struct work_struct *work)
+{
+	struct early_domain_core *core_data;
+	struct device *cpu_device;
+	unsigned long *status;
+	int cpu;
+	int delay;
+	int max_delay;
+
+	core_data = ed_core_data;
+	status = &core_data->pdata->early_domain_status;
+	delay = 40;
+	max_delay = 1000;
+
+	/* Poll on status which will be updated by early-domain running in LK */
+	while (*status) {
+		cpu_relax();
+		msleep(delay);
+		delay = (delay > max_delay ? max_delay : delay + 20);
+	}
+
+	/* An instruction barrier to ensure that execution pipline is flushed
+	 * and instrutions ahead are not executed out of order, leading to
+	 * an unwanted situation where we free resources with a non-zero status.
+	 */
+
+	isb();
+
+	/* Once the status is zero, hot add reserved cpu cores and
+	 * free reserved memory
+	 */
+	unregister_cpu_notifier(&core_data->ed_notifier);
+
+	/* Take attempts to hot add the cpu(s) reserved for early domain
+	 * with delays
+	 */
+	delay = 20;
+	max_delay = 200;
+	while (!cpumask_empty(&core_data->cpumask)) {
+		for_each_cpu(cpu, &core_data->cpumask) {
+			cpu_device = get_cpu_device(cpu);
+			if (!cpu_device) {
+				pr_err("cpu:%d absent in cpu_possible_mask\n"
+					, cpu);
+				cpumask_clear_cpu(cpu, &core_data->cpumask);
+				continue;
+			}
+			if (!device_online(cpu_device))
+				cpumask_clear_cpu(cpu, &core_data->cpumask);
+		}
+		msleep(delay);
+		delay = (delay > max_delay ? max_delay : delay + 20);
+	}
+	free_reserved_lk_mem(core_data->lk_pool_paddr, core_data->lk_pool_size);
+	free_reserved_lk_mem(core_data->early_domain_shm,
+				core_data->early_domain_shm_size);
+
+	/* Remove qos and wake locks */
+
+	pm_qos_remove_request(&core_data->ed_qos_request);
+	__pm_relax(&core_data->ed_wake_lock);
+}
+
+static int early_domain_cpu_notifier(struct notifier_block *self,
+			unsigned long action, void *hcpu)
+{
+	struct early_domain_core *core_data = container_of(self,
+					struct early_domain_core, ed_notifier);
+	unsigned int notifier;
+	unsigned int cpu;
+
+	notifier = NOTIFY_BAD;
+	cpu = (long)hcpu;
+	switch (action & ~CPU_TASKS_FROZEN) {
+	case CPU_UP_PREPARE:
+		if (cpumask_test_cpu(cpu, &core_data->cpumask))
+			pr_err("Early domain services are running on cpu%d\n"
+				, cpu);
+			break;
+	default:
+		notifier = NOTIFY_OK;
+		break;
+	}
+	return notifier;
+}
+
+static int init_early_domain_data(struct early_domain_core *core_data)
+{
+	int cpu;
+	unsigned long cpumask;
+	int ret;
+
+	cpumask_clear(&core_data->cpumask);
+	cpumask = (unsigned long)core_data->pdata->cpumask;
+	for_each_set_bit(cpu, &cpumask, sizeof(cpumask_t))
+		cpumask_set_cpu(cpu, &core_data->cpumask);
+
+	memset(&core_data->ed_qos_request, 0,
+		sizeof(core_data->ed_qos_request));
+	core_data->ed_qos_request.type = PM_QOS_REQ_AFFINE_CORES;
+	core_data->ed_qos_request.cpus_affine = core_data->cpumask;
+	pm_qos_add_request(&core_data->ed_qos_request,
+		PM_QOS_CPU_DMA_LATENCY, PM_QOS_CPU_DMA_LAT_DEFAULT_VALUE);
+	wakeup_source_init(&core_data->ed_wake_lock, "early_domain");
+	__pm_stay_awake(&core_data->ed_wake_lock);
+	core_data->ed_notifier = (struct notifier_block) {
+		.notifier_call = early_domain_cpu_notifier,
+		};
+	ret = register_cpu_notifier(&core_data->ed_notifier);
+	if (ret) {
+		dev_err(&core_data->pdev->dev, "Could not register cpu notifier\n");
+		return ret;
+	}
+	INIT_WORK(&core_data->early_domain_work, early_domain_work);
+	if (!schedule_work(&core_data->early_domain_work)) {
+		dev_err(&core_data->pdev->dev, "Could not schedule work for handoff\n");
+		unregister_cpu_notifier(&core_data->ed_notifier);
+		ret = -ENOMEM;
+	}
+	return ret;
+}
+
+/* It is expected that probe is being called before the initialization of
+ * multimedia drivers like display/camera/audio, so they get correct status
+ * of any active early service.
+ */
+
+static int early_domain_probe(struct platform_device *pdev)
+{
+	int ret;
+	struct early_domain_core *core_data;
+	struct resource res_shm, res_lk;
+	struct device_node *parent, *node;
+
+	ret = 0;
+	parent = of_find_node_by_path("/reserved-memory");
+	if (!parent) {
+		dev_err(&pdev->dev, "Could not find reserved-memory node\n");
+		return -EINVAL;
+	}
+	/* early_domain_shm reserved memory node will be added by bootloader
+	 * dynamically if earlydomain was enabled.
+	 */
+
+	node = of_find_node_by_name(parent, "early_domain_shm");
+	if (!node) {
+		dev_err(&pdev->dev, "Could not find early_domain_shm\n");
+		of_node_put(parent);
+		return -EINVAL;
+	}
+	ret = of_address_to_resource(node, 0, &res_shm);
+	if (ret) {
+		dev_err(&pdev->dev, "No memory address assigned to the region\n");
+		of_node_put(node);
+		of_node_put(parent);
+		return ret;
+	}
+	of_node_put(node);
+	/* lk_pool reserved memory node will be added by bootloader
+	 * dynamically if earlydomain was enabled.
+	 */
+
+	node = of_find_node_by_name(parent, "lk_pool");
+	if (!node) {
+		dev_err(&pdev->dev, "Could not find lk_pool\n");
+		of_node_put(parent);
+		return -EINVAL;
+	}
+	of_node_put(parent);
+	ret = of_address_to_resource(node, 0, &res_lk);
+	if (ret) {
+		dev_err(&pdev->dev, "No memory address assigned to lk_pool\n");
+		of_node_put(node);
+		return ret;
+	}
+	of_node_put(node);
+	core_data = kzalloc(sizeof(*core_data), GFP_KERNEL);
+	if (!core_data)
+		return -ENOMEM;
+	ed_core_data = core_data;
+	core_data->pdata = (struct early_domain_header *)
+			ioremap_nocache(res_shm.start, resource_size(&res_shm));
+	if (!core_data->pdata) {
+		dev_err(&pdev->dev, "%s cannot map reserved early domain space\n"
+			, __func__);
+		ret = -ENOMEM;
+		goto err;
+	}
+	core_data->early_domain_shm = (dma_addr_t)res_shm.start;
+	core_data->early_domain_shm_size = res_shm.end - res_shm.start;
+	core_data->lk_pool_paddr = (dma_addr_t)res_lk.start;
+	core_data->lk_pool_size = res_lk.end - res_lk.start;
+	ret = memcmp(core_data->pdata->magic, EARLY_DOMAIN_MAGIC,
+			MAGIC_SIZE);
+	if (ret) {
+		dev_err(&pdev->dev, "Early domain reserved page has been corrupted\n");
+		ret = -EINVAL;
+		goto err;
+	}
+	core_data->pdev = pdev;
+	ret = init_early_domain_data(core_data);
+	if (ret)
+		goto err;
+	platform_set_drvdata(pdev, core_data);
+	early_domain_enabled = true;
+	active_early_services();
+	return ret;
+err:
+	if (pm_qos_request_active(&core_data->ed_qos_request))
+		pm_qos_remove_request(&core_data->ed_qos_request);
+	if (core_data->ed_wake_lock.active)
+		wakeup_source_trash(&core_data->ed_wake_lock);
+	kfree(core_data);
+	return ret;
+}
+
+static int early_domain_remove(struct platform_device *pdev)
+{
+	struct early_domain_core *core_data;
+
+	core_data = platform_get_drvdata(pdev);
+	pm_qos_remove_request(&core_data->ed_qos_request);
+	__pm_relax(&core_data->ed_wake_lock);
+	unregister_cpu_notifier(&core_data->ed_notifier);
+	kfree(core_data);
+	return 0;
+}
+
+static const struct of_device_id early_domain_table[] = {
+	{ .compatible = "qcom,early_domain" },
+	{}
+};
+
+static struct platform_driver early_domain_driver = {
+	.probe = early_domain_probe,
+	.remove = early_domain_remove,
+	.driver = {
+		.name = "early_domain",
+		.owner = THIS_MODULE,
+		.of_match_table = early_domain_table,
+	},
+};
+
+static int __init earlydom_init(void)
+{
+	return platform_driver_register(&early_domain_driver);
+}
+
+fs_initcall(earlydom_init);
+
+static void __exit earlydom_exit(void)
+{
+	platform_driver_unregister(&early_domain_driver);
+}
+
+module_exit(earlydom_exit);
+MODULE_DESCRIPTION("QCOM EARLYDOMAIN DRIVER");
+MODULE_LICENSE("GPL v2");
+MODULE_DEVICE_TABLE(of, early_domain_table);
diff --git a/include/soc/qcom/early_domain.h b/include/soc/qcom/early_domain.h
new file mode 100644
index 000000000000..076f2d6fac2b
--- /dev/null
+++ b/include/soc/qcom/early_domain.h
@@ -0,0 +1,98 @@
+/* Copyright (c) 2018, The Linux Foundation. All rights reserved.
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 and
+ * only version 2 as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ */
+
+/* Early domain services invoked in bootloaders run in parallel after
+ * kernel takes over. One page in memory is reserved to pass information
+ * between bootloader and kernel. This page has a header to capture status,
+ * request and cpumask described in structure early_domain_header. Early
+ * domain core driver in kernel reads this header to decide the status of
+ * services and takes necessary action. The rest of the page is intended to
+ * pass service specific information. Offset for service specific area are
+ * defined in macros, and its the service specific driver's responsiblity
+ * to operate in their defined areas to pass service specific information.
+ * *
+ * *
+ * *
+ * *****************************************
+ * *              Header                   *
+ * *                                       *
+ * *****************************************
+ * *                                       *
+ * *              Early display            *
+ * *                                       *
+ * *                                       *
+ * *****************************************
+ * *                                       *
+ * *              Early camera             *
+ * *                                       *
+ * *                                       *
+ * *****************************************
+ * *                                       *
+ * *              Early audio              *
+ * *                                       *
+ * *                                       *
+ * *****************************************
+ * *
+ */
+
+enum service_id {
+	EARLY_DOMAIN_CORE = 0,
+	EARLY_DISPLAY,
+	EARLY_CAMERA,
+	EARLY_AUDIO,
+};
+
+#ifdef CONFIG_QCOM_EARLY_DOMAIN
+#include <linux/workqueue.h>
+#include <linux/cpumask.h>
+#include <linux/pm_qos.h>
+#include <linux/notifier.h>
+
+#define EARLY_DOMAIN_MAGIC	"ERLYDOM"
+#define MAGIC_SIZE		8
+#define NUM_SERVICES		3
+#define SERVICE_SHARED_MEM_SIZE		((PAGE_SIZE)/(NUM_SERVICES))
+
+struct early_domain_header {
+	char magic[MAGIC_SIZE];
+	unsigned long cpumask;
+	unsigned long early_domain_status;
+	unsigned long early_domain_request;
+};
+
+struct early_domain_core {
+	struct platform_device *pdev;
+	struct early_domain_header *pdata;
+	struct work_struct early_domain_work;
+	phys_addr_t lk_pool_paddr;
+	size_t lk_pool_size;
+	phys_addr_t early_domain_shm;
+	size_t early_domain_shm_size;
+	cpumask_t cpumask;
+	struct notifier_block ed_notifier;
+	struct pm_qos_request ed_qos_request;
+	struct wakeup_source ed_wake_lock;
+};
+
+void request_early_service_shutdown(enum service_id);
+bool get_early_service_status(enum service_id sid);
+void *get_service_shared_mem_start(enum service_id sid);
+
+#else
+
+static inline void request_early_service_shutdown(enum service_id sid) {}
+static inline bool get_early_service_status(enum service_id sid)
+						{ return false; }
+static inline void *get_service_shared_mem_start(enum service_id sid)
+						{ return NULL; }
+
+#endif