| // 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; |
| } |