1 // SPDX-License-Identifier: GPL-2.0-only 2 /* 3 * OMAP IOMMU quirks for various TI SoCs 4 * 5 * Copyright (C) 2015-2019 Texas Instruments Incorporated - https://www.ti.com/ 6 * Suman Anna <s-anna@ti.com> 7 */ 8 9 #include <linux/platform_device.h> 10 #include <linux/err.h> 11 #include <linux/clk.h> 12 #include <linux/list.h> 13 14 #include "clockdomain.h" 15 #include "powerdomain.h" 16 #include "common.h" 17 18 struct pwrdm_link { 19 struct device *dev; 20 struct powerdomain *pwrdm; 21 struct list_head node; 22 }; 23 24 static DEFINE_SPINLOCK(iommu_lock); 25 static struct clockdomain *emu_clkdm; 26 static atomic_t emu_count; 27 28 static void omap_iommu_dra7_emu_swsup_config(struct platform_device *pdev, 29 bool enable) 30 { 31 struct device_node *np = pdev->dev.of_node; 32 unsigned long flags; 33 34 if (!of_device_is_compatible(np, "ti,dra7-dsp-iommu")) 35 return; 36 37 if (!emu_clkdm) { 38 emu_clkdm = clkdm_lookup("emu_clkdm"); 39 if (WARN_ON_ONCE(!emu_clkdm)) 40 return; 41 } 42 43 spin_lock_irqsave(&iommu_lock, flags); 44 45 if (enable && (atomic_inc_return(&emu_count) == 1)) 46 clkdm_deny_idle(emu_clkdm); 47 else if (!enable && (atomic_dec_return(&emu_count) == 0)) 48 clkdm_allow_idle(emu_clkdm); 49 50 spin_unlock_irqrestore(&iommu_lock, flags); 51 } 52 53 static struct powerdomain *_get_pwrdm(struct device *dev) 54 { 55 struct clk *clk; 56 struct clk_hw_omap *hwclk; 57 struct clockdomain *clkdm; 58 struct powerdomain *pwrdm = NULL; 59 struct pwrdm_link *entry; 60 unsigned long flags; 61 static LIST_HEAD(cache); 62 63 spin_lock_irqsave(&iommu_lock, flags); 64 65 list_for_each_entry(entry, &cache, node) { 66 if (entry->dev == dev) { 67 pwrdm = entry->pwrdm; 68 break; 69 } 70 } 71 72 spin_unlock_irqrestore(&iommu_lock, flags); 73 74 if (pwrdm) 75 return pwrdm; 76 77 clk = of_clk_get(dev->of_node->parent, 0); 78 if (IS_ERR(clk)) { 79 dev_err(dev, "no fck found\n"); 80 return NULL; 81 } 82 83 hwclk = to_clk_hw_omap(__clk_get_hw(clk)); 84 clk_put(clk); 85 if (!hwclk || !hwclk->clkdm_name) { 86 dev_err(dev, "no hwclk data\n"); 87 return NULL; 88 } 89 90 clkdm = clkdm_lookup(hwclk->clkdm_name); 91 if (!clkdm) { 92 dev_err(dev, "clkdm not found: %s\n", hwclk->clkdm_name); 93 return NULL; 94 } 95 96 pwrdm = clkdm_get_pwrdm(clkdm); 97 if (!pwrdm) { 98 dev_err(dev, "pwrdm not found: %s\n", clkdm->name); 99 return NULL; 100 } 101 102 entry = kmalloc(sizeof(*entry), GFP_KERNEL); 103 if (entry) { 104 entry->dev = dev; 105 entry->pwrdm = pwrdm; 106 spin_lock_irqsave(&iommu_lock, flags); 107 list_add(&entry->node, &cache); 108 spin_unlock_irqrestore(&iommu_lock, flags); 109 } 110 111 return pwrdm; 112 } 113 114 int omap_iommu_set_pwrdm_constraint(struct platform_device *pdev, bool request, 115 u8 *pwrst) 116 { 117 struct powerdomain *pwrdm; 118 u8 next_pwrst; 119 int ret = 0; 120 121 pwrdm = _get_pwrdm(&pdev->dev); 122 if (!pwrdm) 123 return -ENODEV; 124 125 if (request) { 126 *pwrst = pwrdm_read_next_pwrst(pwrdm); 127 omap_iommu_dra7_emu_swsup_config(pdev, true); 128 } 129 130 if (*pwrst > PWRDM_POWER_RET) 131 goto out; 132 133 next_pwrst = request ? PWRDM_POWER_ON : *pwrst; 134 135 ret = pwrdm_set_next_pwrst(pwrdm, next_pwrst); 136 137 out: 138 if (!request) 139 omap_iommu_dra7_emu_swsup_config(pdev, false); 140 141 return ret; 142 } 143