| // SPDX-License-Identifier: GPL-2.0 | 
 | /* | 
 |  * Marvell Dove PMU support | 
 |  */ | 
 | #include <linux/io.h> | 
 | #include <linux/irq.h> | 
 | #include <linux/irqdomain.h> | 
 | #include <linux/of.h> | 
 | #include <linux/of_irq.h> | 
 | #include <linux/of_address.h> | 
 | #include <linux/platform_device.h> | 
 | #include <linux/pm_domain.h> | 
 | #include <linux/reset.h> | 
 | #include <linux/reset-controller.h> | 
 | #include <linux/sched.h> | 
 | #include <linux/slab.h> | 
 | #include <linux/soc/dove/pmu.h> | 
 | #include <linux/spinlock.h> | 
 |  | 
 | #define NR_PMU_IRQS		7 | 
 |  | 
 | #define PMC_SW_RST		0x30 | 
 | #define PMC_IRQ_CAUSE		0x50 | 
 | #define PMC_IRQ_MASK		0x54 | 
 |  | 
 | #define PMU_PWR			0x10 | 
 | #define PMU_ISO			0x58 | 
 |  | 
 | struct pmu_data { | 
 | 	spinlock_t lock; | 
 | 	struct device_node *of_node; | 
 | 	void __iomem *pmc_base; | 
 | 	void __iomem *pmu_base; | 
 | 	struct irq_chip_generic *irq_gc; | 
 | 	struct irq_domain *irq_domain; | 
 | #ifdef CONFIG_RESET_CONTROLLER | 
 | 	struct reset_controller_dev reset; | 
 | #endif | 
 | }; | 
 |  | 
 | /* | 
 |  * The PMU contains a register to reset various subsystems within the | 
 |  * SoC.  Export this as a reset controller. | 
 |  */ | 
 | #ifdef CONFIG_RESET_CONTROLLER | 
 | #define rcdev_to_pmu(rcdev) container_of(rcdev, struct pmu_data, reset) | 
 |  | 
 | static int pmu_reset_reset(struct reset_controller_dev *rc, unsigned long id) | 
 | { | 
 | 	struct pmu_data *pmu = rcdev_to_pmu(rc); | 
 | 	unsigned long flags; | 
 | 	u32 val; | 
 |  | 
 | 	spin_lock_irqsave(&pmu->lock, flags); | 
 | 	val = readl_relaxed(pmu->pmc_base + PMC_SW_RST); | 
 | 	writel_relaxed(val & ~BIT(id), pmu->pmc_base + PMC_SW_RST); | 
 | 	writel_relaxed(val | BIT(id), pmu->pmc_base + PMC_SW_RST); | 
 | 	spin_unlock_irqrestore(&pmu->lock, flags); | 
 |  | 
 | 	return 0; | 
 | } | 
 |  | 
 | static int pmu_reset_assert(struct reset_controller_dev *rc, unsigned long id) | 
 | { | 
 | 	struct pmu_data *pmu = rcdev_to_pmu(rc); | 
 | 	unsigned long flags; | 
 | 	u32 val = ~BIT(id); | 
 |  | 
 | 	spin_lock_irqsave(&pmu->lock, flags); | 
 | 	val &= readl_relaxed(pmu->pmc_base + PMC_SW_RST); | 
 | 	writel_relaxed(val, pmu->pmc_base + PMC_SW_RST); | 
 | 	spin_unlock_irqrestore(&pmu->lock, flags); | 
 |  | 
 | 	return 0; | 
 | } | 
 |  | 
 | static int pmu_reset_deassert(struct reset_controller_dev *rc, unsigned long id) | 
 | { | 
 | 	struct pmu_data *pmu = rcdev_to_pmu(rc); | 
 | 	unsigned long flags; | 
 | 	u32 val = BIT(id); | 
 |  | 
 | 	spin_lock_irqsave(&pmu->lock, flags); | 
 | 	val |= readl_relaxed(pmu->pmc_base + PMC_SW_RST); | 
 | 	writel_relaxed(val, pmu->pmc_base + PMC_SW_RST); | 
 | 	spin_unlock_irqrestore(&pmu->lock, flags); | 
 |  | 
 | 	return 0; | 
 | } | 
 |  | 
 | static const struct reset_control_ops pmu_reset_ops = { | 
 | 	.reset = pmu_reset_reset, | 
 | 	.assert = pmu_reset_assert, | 
 | 	.deassert = pmu_reset_deassert, | 
 | }; | 
 |  | 
 | static struct reset_controller_dev pmu_reset __initdata = { | 
 | 	.ops = &pmu_reset_ops, | 
 | 	.owner = THIS_MODULE, | 
 | 	.nr_resets = 32, | 
 | }; | 
 |  | 
 | static void __init pmu_reset_init(struct pmu_data *pmu) | 
 | { | 
 | 	int ret; | 
 |  | 
 | 	pmu->reset = pmu_reset; | 
 | 	pmu->reset.of_node = pmu->of_node; | 
 |  | 
 | 	ret = reset_controller_register(&pmu->reset); | 
 | 	if (ret) | 
 | 		pr_err("pmu: %s failed: %d\n", "reset_controller_register", ret); | 
 | } | 
 | #else | 
 | static void __init pmu_reset_init(struct pmu_data *pmu) | 
 | { | 
 | } | 
 | #endif | 
 |  | 
 | struct pmu_domain { | 
 | 	struct pmu_data *pmu; | 
 | 	u32 pwr_mask; | 
 | 	u32 rst_mask; | 
 | 	u32 iso_mask; | 
 | 	struct generic_pm_domain base; | 
 | }; | 
 |  | 
 | #define to_pmu_domain(dom) container_of(dom, struct pmu_domain, base) | 
 |  | 
 | /* | 
 |  * This deals with the "old" Marvell sequence of bringing a power domain | 
 |  * down/up, which is: apply power, release reset, disable isolators. | 
 |  * | 
 |  * Later devices apparantly use a different sequence: power up, disable | 
 |  * isolators, assert repair signal, enable SRMA clock, enable AXI clock, | 
 |  * enable module clock, deassert reset. | 
 |  * | 
 |  * Note: reading the assembly, it seems that the IO accessors have an | 
 |  * unfortunate side-effect - they cause memory already read into registers | 
 |  * for the if () to be re-read for the bit-set or bit-clear operation. | 
 |  * The code is written to avoid this. | 
 |  */ | 
 | static int pmu_domain_power_off(struct generic_pm_domain *domain) | 
 | { | 
 | 	struct pmu_domain *pmu_dom = to_pmu_domain(domain); | 
 | 	struct pmu_data *pmu = pmu_dom->pmu; | 
 | 	unsigned long flags; | 
 | 	unsigned int val; | 
 | 	void __iomem *pmu_base = pmu->pmu_base; | 
 | 	void __iomem *pmc_base = pmu->pmc_base; | 
 |  | 
 | 	spin_lock_irqsave(&pmu->lock, flags); | 
 |  | 
 | 	/* Enable isolators */ | 
 | 	if (pmu_dom->iso_mask) { | 
 | 		val = ~pmu_dom->iso_mask; | 
 | 		val &= readl_relaxed(pmu_base + PMU_ISO); | 
 | 		writel_relaxed(val, pmu_base + PMU_ISO); | 
 | 	} | 
 |  | 
 | 	/* Reset unit */ | 
 | 	if (pmu_dom->rst_mask) { | 
 | 		val = ~pmu_dom->rst_mask; | 
 | 		val &= readl_relaxed(pmc_base + PMC_SW_RST); | 
 | 		writel_relaxed(val, pmc_base + PMC_SW_RST); | 
 | 	} | 
 |  | 
 | 	/* Power down */ | 
 | 	val = readl_relaxed(pmu_base + PMU_PWR) | pmu_dom->pwr_mask; | 
 | 	writel_relaxed(val, pmu_base + PMU_PWR); | 
 |  | 
 | 	spin_unlock_irqrestore(&pmu->lock, flags); | 
 |  | 
 | 	return 0; | 
 | } | 
 |  | 
 | static int pmu_domain_power_on(struct generic_pm_domain *domain) | 
 | { | 
 | 	struct pmu_domain *pmu_dom = to_pmu_domain(domain); | 
 | 	struct pmu_data *pmu = pmu_dom->pmu; | 
 | 	unsigned long flags; | 
 | 	unsigned int val; | 
 | 	void __iomem *pmu_base = pmu->pmu_base; | 
 | 	void __iomem *pmc_base = pmu->pmc_base; | 
 |  | 
 | 	spin_lock_irqsave(&pmu->lock, flags); | 
 |  | 
 | 	/* Power on */ | 
 | 	val = ~pmu_dom->pwr_mask & readl_relaxed(pmu_base + PMU_PWR); | 
 | 	writel_relaxed(val, pmu_base + PMU_PWR); | 
 |  | 
 | 	/* Release reset */ | 
 | 	if (pmu_dom->rst_mask) { | 
 | 		val = pmu_dom->rst_mask; | 
 | 		val |= readl_relaxed(pmc_base + PMC_SW_RST); | 
 | 		writel_relaxed(val, pmc_base + PMC_SW_RST); | 
 | 	} | 
 |  | 
 | 	/* Disable isolators */ | 
 | 	if (pmu_dom->iso_mask) { | 
 | 		val = pmu_dom->iso_mask; | 
 | 		val |= readl_relaxed(pmu_base + PMU_ISO); | 
 | 		writel_relaxed(val, pmu_base + PMU_ISO); | 
 | 	} | 
 |  | 
 | 	spin_unlock_irqrestore(&pmu->lock, flags); | 
 |  | 
 | 	return 0; | 
 | } | 
 |  | 
 | static void __pmu_domain_register(struct pmu_domain *domain, | 
 | 	struct device_node *np) | 
 | { | 
 | 	unsigned int val = readl_relaxed(domain->pmu->pmu_base + PMU_PWR); | 
 |  | 
 | 	domain->base.power_off = pmu_domain_power_off; | 
 | 	domain->base.power_on = pmu_domain_power_on; | 
 |  | 
 | 	pm_genpd_init(&domain->base, NULL, !(val & domain->pwr_mask)); | 
 |  | 
 | 	if (np) | 
 | 		of_genpd_add_provider_simple(np, &domain->base); | 
 | } | 
 |  | 
 | /* PMU IRQ controller */ | 
 | static void pmu_irq_handler(struct irq_desc *desc) | 
 | { | 
 | 	struct pmu_data *pmu = irq_desc_get_handler_data(desc); | 
 | 	struct irq_chip_generic *gc = pmu->irq_gc; | 
 | 	struct irq_domain *domain = pmu->irq_domain; | 
 | 	void __iomem *base = gc->reg_base; | 
 | 	u32 stat = readl_relaxed(base + PMC_IRQ_CAUSE) & gc->mask_cache; | 
 | 	u32 done = ~0; | 
 |  | 
 | 	if (stat == 0) { | 
 | 		handle_bad_irq(desc); | 
 | 		return; | 
 | 	} | 
 |  | 
 | 	while (stat) { | 
 | 		u32 hwirq = fls(stat) - 1; | 
 |  | 
 | 		stat &= ~(1 << hwirq); | 
 | 		done &= ~(1 << hwirq); | 
 |  | 
 | 		generic_handle_irq(irq_find_mapping(domain, hwirq)); | 
 | 	} | 
 |  | 
 | 	/* | 
 | 	 * The PMU mask register is not RW0C: it is RW.  This means that | 
 | 	 * the bits take whatever value is written to them; if you write | 
 | 	 * a '1', you will set the interrupt. | 
 | 	 * | 
 | 	 * Unfortunately this means there is NO race free way to clear | 
 | 	 * these interrupts. | 
 | 	 * | 
 | 	 * So, let's structure the code so that the window is as small as | 
 | 	 * possible. | 
 | 	 */ | 
 | 	irq_gc_lock(gc); | 
 | 	done &= readl_relaxed(base + PMC_IRQ_CAUSE); | 
 | 	writel_relaxed(done, base + PMC_IRQ_CAUSE); | 
 | 	irq_gc_unlock(gc); | 
 | } | 
 |  | 
 | static int __init dove_init_pmu_irq(struct pmu_data *pmu, int irq) | 
 | { | 
 | 	const char *name = "pmu_irq"; | 
 | 	struct irq_chip_generic *gc; | 
 | 	struct irq_domain *domain; | 
 | 	int ret; | 
 |  | 
 | 	/* mask and clear all interrupts */ | 
 | 	writel(0, pmu->pmc_base + PMC_IRQ_MASK); | 
 | 	writel(0, pmu->pmc_base + PMC_IRQ_CAUSE); | 
 |  | 
 | 	domain = irq_domain_add_linear(pmu->of_node, NR_PMU_IRQS, | 
 | 				       &irq_generic_chip_ops, NULL); | 
 | 	if (!domain) { | 
 | 		pr_err("%s: unable to add irq domain\n", name); | 
 | 		return -ENOMEM; | 
 | 	} | 
 |  | 
 | 	ret = irq_alloc_domain_generic_chips(domain, NR_PMU_IRQS, 1, name, | 
 | 					     handle_level_irq, | 
 | 					     IRQ_NOREQUEST | IRQ_NOPROBE, 0, | 
 | 					     IRQ_GC_INIT_MASK_CACHE); | 
 | 	if (ret) { | 
 | 		pr_err("%s: unable to alloc irq domain gc: %d\n", name, ret); | 
 | 		irq_domain_remove(domain); | 
 | 		return ret; | 
 | 	} | 
 |  | 
 | 	gc = irq_get_domain_generic_chip(domain, 0); | 
 | 	gc->reg_base = pmu->pmc_base; | 
 | 	gc->chip_types[0].regs.mask = PMC_IRQ_MASK; | 
 | 	gc->chip_types[0].chip.irq_mask = irq_gc_mask_clr_bit; | 
 | 	gc->chip_types[0].chip.irq_unmask = irq_gc_mask_set_bit; | 
 |  | 
 | 	pmu->irq_domain = domain; | 
 | 	pmu->irq_gc = gc; | 
 |  | 
 | 	irq_set_handler_data(irq, pmu); | 
 | 	irq_set_chained_handler(irq, pmu_irq_handler); | 
 |  | 
 | 	return 0; | 
 | } | 
 |  | 
 | int __init dove_init_pmu_legacy(const struct dove_pmu_initdata *initdata) | 
 | { | 
 | 	const struct dove_pmu_domain_initdata *domain_initdata; | 
 | 	struct pmu_data *pmu; | 
 | 	int ret; | 
 |  | 
 | 	pmu = kzalloc(sizeof(*pmu), GFP_KERNEL); | 
 | 	if (!pmu) | 
 | 		return -ENOMEM; | 
 |  | 
 | 	spin_lock_init(&pmu->lock); | 
 | 	pmu->pmc_base = initdata->pmc_base; | 
 | 	pmu->pmu_base = initdata->pmu_base; | 
 |  | 
 | 	pmu_reset_init(pmu); | 
 | 	for (domain_initdata = initdata->domains; domain_initdata->name; | 
 | 	     domain_initdata++) { | 
 | 		struct pmu_domain *domain; | 
 |  | 
 | 		domain = kzalloc(sizeof(*domain), GFP_KERNEL); | 
 | 		if (domain) { | 
 | 			domain->pmu = pmu; | 
 | 			domain->pwr_mask = domain_initdata->pwr_mask; | 
 | 			domain->rst_mask = domain_initdata->rst_mask; | 
 | 			domain->iso_mask = domain_initdata->iso_mask; | 
 | 			domain->base.name = domain_initdata->name; | 
 |  | 
 | 			__pmu_domain_register(domain, NULL); | 
 | 		} | 
 | 	} | 
 |  | 
 | 	ret = dove_init_pmu_irq(pmu, initdata->irq); | 
 | 	if (ret) | 
 | 		pr_err("dove_init_pmu_irq() failed: %d\n", ret); | 
 |  | 
 | 	if (pmu->irq_domain) | 
 | 		irq_domain_associate_many(pmu->irq_domain, | 
 | 					  initdata->irq_domain_start, | 
 | 					  0, NR_PMU_IRQS); | 
 |  | 
 | 	return 0; | 
 | } | 
 |  | 
 | /* | 
 |  * pmu: power-manager@d0000 { | 
 |  *	compatible = "marvell,dove-pmu"; | 
 |  *	reg = <0xd0000 0x8000> <0xd8000 0x8000>; | 
 |  *	interrupts = <33>; | 
 |  *	interrupt-controller; | 
 |  *	#reset-cells = 1; | 
 |  *	vpu_domain: vpu-domain { | 
 |  *		#power-domain-cells = <0>; | 
 |  *		marvell,pmu_pwr_mask = <0x00000008>; | 
 |  *		marvell,pmu_iso_mask = <0x00000001>; | 
 |  *		resets = <&pmu 16>; | 
 |  *	}; | 
 |  *	gpu_domain: gpu-domain { | 
 |  *		#power-domain-cells = <0>; | 
 |  *		marvell,pmu_pwr_mask = <0x00000004>; | 
 |  *		marvell,pmu_iso_mask = <0x00000002>; | 
 |  *		resets = <&pmu 18>; | 
 |  *	}; | 
 |  * }; | 
 |  */ | 
 | int __init dove_init_pmu(void) | 
 | { | 
 | 	struct device_node *np_pmu, *domains_node, *np; | 
 | 	struct pmu_data *pmu; | 
 | 	int ret, parent_irq; | 
 |  | 
 | 	/* Lookup the PMU node */ | 
 | 	np_pmu = of_find_compatible_node(NULL, NULL, "marvell,dove-pmu"); | 
 | 	if (!np_pmu) | 
 | 		return 0; | 
 |  | 
 | 	domains_node = of_get_child_by_name(np_pmu, "domains"); | 
 | 	if (!domains_node) { | 
 | 		pr_err("%s: failed to find domains sub-node\n", np_pmu->name); | 
 | 		return 0; | 
 | 	} | 
 |  | 
 | 	pmu = kzalloc(sizeof(*pmu), GFP_KERNEL); | 
 | 	if (!pmu) | 
 | 		return -ENOMEM; | 
 |  | 
 | 	spin_lock_init(&pmu->lock); | 
 | 	pmu->of_node = np_pmu; | 
 | 	pmu->pmc_base = of_iomap(pmu->of_node, 0); | 
 | 	pmu->pmu_base = of_iomap(pmu->of_node, 1); | 
 | 	if (!pmu->pmc_base || !pmu->pmu_base) { | 
 | 		pr_err("%s: failed to map PMU\n", np_pmu->name); | 
 | 		iounmap(pmu->pmu_base); | 
 | 		iounmap(pmu->pmc_base); | 
 | 		kfree(pmu); | 
 | 		return -ENOMEM; | 
 | 	} | 
 |  | 
 | 	pmu_reset_init(pmu); | 
 |  | 
 | 	for_each_available_child_of_node(domains_node, np) { | 
 | 		struct of_phandle_args args; | 
 | 		struct pmu_domain *domain; | 
 |  | 
 | 		domain = kzalloc(sizeof(*domain), GFP_KERNEL); | 
 | 		if (!domain) | 
 | 			break; | 
 |  | 
 | 		domain->pmu = pmu; | 
 | 		domain->base.name = kstrdup(np->name, GFP_KERNEL); | 
 | 		if (!domain->base.name) { | 
 | 			kfree(domain); | 
 | 			break; | 
 | 		} | 
 |  | 
 | 		of_property_read_u32(np, "marvell,pmu_pwr_mask", | 
 | 				     &domain->pwr_mask); | 
 | 		of_property_read_u32(np, "marvell,pmu_iso_mask", | 
 | 				     &domain->iso_mask); | 
 |  | 
 | 		/* | 
 | 		 * We parse the reset controller property directly here | 
 | 		 * to ensure that we can operate when the reset controller | 
 | 		 * support is not configured into the kernel. | 
 | 		 */ | 
 | 		ret = of_parse_phandle_with_args(np, "resets", "#reset-cells", | 
 | 						 0, &args); | 
 | 		if (ret == 0) { | 
 | 			if (args.np == pmu->of_node) | 
 | 				domain->rst_mask = BIT(args.args[0]); | 
 | 			of_node_put(args.np); | 
 | 		} | 
 |  | 
 | 		__pmu_domain_register(domain, np); | 
 | 	} | 
 |  | 
 | 	/* Loss of the interrupt controller is not a fatal error. */ | 
 | 	parent_irq = irq_of_parse_and_map(pmu->of_node, 0); | 
 | 	if (!parent_irq) { | 
 | 		pr_err("%s: no interrupt specified\n", np_pmu->name); | 
 | 	} else { | 
 | 		ret = dove_init_pmu_irq(pmu, parent_irq); | 
 | 		if (ret) | 
 | 			pr_err("dove_init_pmu_irq() failed: %d\n", ret); | 
 | 	} | 
 |  | 
 | 	return 0; | 
 | } |