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author | Linus Torvalds <torvalds@linux-foundation.org> | 2015-09-01 13:00:04 -0700 |
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committer | Linus Torvalds <torvalds@linux-foundation.org> | 2015-09-01 13:00:04 -0700 |
commit | 102178108e2246cb4b329d3fb7872cd3d7120205 (patch) | |
tree | 3c0720bd96e613631d3983bba385fc675dceb08e /drivers/soc/dove/pmu.c | |
parent | 50686e8a3aed2f5d295e9d2e79ff43df461c7b76 (diff) | |
parent | 21815b9a24c6e6d3488703609561bd2892d3d9f3 (diff) | |
download | op-kernel-dev-102178108e2246cb4b329d3fb7872cd3d7120205.zip op-kernel-dev-102178108e2246cb4b329d3fb7872cd3d7120205.tar.gz |
Merge tag 'armsoc-drivers' of git://git.kernel.org/pub/scm/linux/kernel/git/arm/arm-soc
Pull ARM SoC driver updates from Olof Johansson:
"Some releases this branch is nearly empty, others we have more stuff.
It tends to gather drivers that need SoC modification or dependencies
such that they have to (also) go in through our tree.
For this release, we have merged in part of the reset controller tree
(with handshake that the parts we have merged in will remain stable),
as well as dependencies on a few clock branches.
In general, new items here are:
- Qualcomm driver for SMM/SMD, which is how they communicate with the
coprocessors on (some) of their platforms
- memory controller work for ARM's PL172 memory controller
- reset drivers for various platforms
- PMU power domain support for Marvell platforms
- Tegra support for T132/T210 SoCs: PMC, fuse, memory controller
per-SoC support"
* tag 'armsoc-drivers' of git://git.kernel.org/pub/scm/linux/kernel/git/arm/arm-soc: (49 commits)
ARM: tegra: cpuidle: implement cpuidle_state.enter_freeze()
ARM: tegra: Disable cpuidle if PSCI is available
soc/tegra: pmc: Use existing pclk reference
soc/tegra: pmc: Remove unnecessary return statement
soc: tegra: Remove redundant $(CONFIG_ARCH_TEGRA) in Makefile
memory: tegra: Add Tegra210 support
memory: tegra: Add support for a variable-size client ID bitfield
clk: shmobile: rz: Add CPG/MSTP Clock Domain support
clk: shmobile: rcar-gen2: Add CPG/MSTP Clock Domain support
clk: shmobile: r8a7779: Add CPG/MSTP Clock Domain support
clk: shmobile: r8a7778: Add CPG/MSTP Clock Domain support
clk: shmobile: Add CPG/MSTP Clock Domain support
ARM: dove: create a proper PMU driver for power domains, PMU IRQs and resets
reset: reset-zynq: Adding support for Xilinx Zynq reset controller.
docs: dts: Added documentation for Xilinx Zynq Reset Controller bindings.
MIPS: ath79: Add the reset controller to the AR9132 dtsi
reset: Add a driver for the reset controller on the AR71XX/AR9XXX
devicetree: Add bindings for the ATH79 reset controller
reset: socfpga: Update reset-socfpga to read the altr,modrst-offset property
doc: dt: add documentation for lpc1850-rgu reset driver
...
Diffstat (limited to 'drivers/soc/dove/pmu.c')
-rw-r--r-- | drivers/soc/dove/pmu.c | 412 |
1 files changed, 412 insertions, 0 deletions
diff --git a/drivers/soc/dove/pmu.c b/drivers/soc/dove/pmu.c new file mode 100644 index 0000000..6792aae --- /dev/null +++ b/drivers/soc/dove/pmu.c @@ -0,0 +1,412 @@ +/* + * 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 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(unsigned int irq, struct irq_desc *desc) +{ + struct pmu_data *pmu = irq_get_handler_data(irq); + 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(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; +} + +/* + * 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); + } + pm_genpd_poweroff_unused(); + + /* 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; +} |