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1// SPDX-License-Identifier: GPL-2.0-only2/*3 * Copyright (c) 2015, Fuzhou Rockchip Electronics Co., Ltd4 */5 6#include <linux/clk.h>7#include <linux/interrupt.h>8#include <linux/io.h>9#include <linux/kernel.h>10#include <linux/mailbox_controller.h>11#include <linux/of.h>12#include <linux/module.h>13#include <linux/platform_device.h>14 15#define MAILBOX_A2B_INTEN 0x0016#define MAILBOX_A2B_STATUS 0x0417#define MAILBOX_A2B_CMD(x) (0x08 + (x) * 8)18#define MAILBOX_A2B_DAT(x) (0x0c + (x) * 8)19 20#define MAILBOX_B2A_INTEN 0x2821#define MAILBOX_B2A_STATUS 0x2C22#define MAILBOX_B2A_CMD(x) (0x30 + (x) * 8)23#define MAILBOX_B2A_DAT(x) (0x34 + (x) * 8)24 25struct rockchip_mbox_msg {26 u32 cmd;27 int rx_size;28};29 30struct rockchip_mbox_data {31 int num_chans;32};33 34struct rockchip_mbox_chan {35 int idx;36 int irq;37 struct rockchip_mbox_msg *msg;38 struct rockchip_mbox *mb;39};40 41struct rockchip_mbox {42 struct mbox_controller mbox;43 struct clk *pclk;44 void __iomem *mbox_base;45 46 /* The maximum size of buf for each channel */47 u32 buf_size;48 49 struct rockchip_mbox_chan *chans;50};51 52static int rockchip_mbox_send_data(struct mbox_chan *chan, void *data)53{54 struct rockchip_mbox *mb = dev_get_drvdata(chan->mbox->dev);55 struct rockchip_mbox_msg *msg = data;56 struct rockchip_mbox_chan *chans = mb->chans;57 58 if (!msg)59 return -EINVAL;60 61 if (msg->rx_size > mb->buf_size) {62 dev_err(mb->mbox.dev, "Transmit size over buf size(%d)\n",63 mb->buf_size);64 return -EINVAL;65 }66 67 dev_dbg(mb->mbox.dev, "Chan[%d]: A2B message, cmd 0x%08x\n",68 chans->idx, msg->cmd);69 70 mb->chans[chans->idx].msg = msg;71 72 writel_relaxed(msg->cmd, mb->mbox_base + MAILBOX_A2B_CMD(chans->idx));73 writel_relaxed(msg->rx_size, mb->mbox_base +74 MAILBOX_A2B_DAT(chans->idx));75 76 return 0;77}78 79static int rockchip_mbox_startup(struct mbox_chan *chan)80{81 struct rockchip_mbox *mb = dev_get_drvdata(chan->mbox->dev);82 83 /* Enable all B2A interrupts */84 writel_relaxed((1 << mb->mbox.num_chans) - 1,85 mb->mbox_base + MAILBOX_B2A_INTEN);86 87 return 0;88}89 90static void rockchip_mbox_shutdown(struct mbox_chan *chan)91{92 struct rockchip_mbox *mb = dev_get_drvdata(chan->mbox->dev);93 struct rockchip_mbox_chan *chans = mb->chans;94 95 /* Disable all B2A interrupts */96 writel_relaxed(0, mb->mbox_base + MAILBOX_B2A_INTEN);97 98 mb->chans[chans->idx].msg = NULL;99}100 101static const struct mbox_chan_ops rockchip_mbox_chan_ops = {102 .send_data = rockchip_mbox_send_data,103 .startup = rockchip_mbox_startup,104 .shutdown = rockchip_mbox_shutdown,105};106 107static irqreturn_t rockchip_mbox_irq(int irq, void *dev_id)108{109 int idx;110 struct rockchip_mbox *mb = (struct rockchip_mbox *)dev_id;111 u32 status = readl_relaxed(mb->mbox_base + MAILBOX_B2A_STATUS);112 113 for (idx = 0; idx < mb->mbox.num_chans; idx++) {114 if ((status & (1 << idx)) && (irq == mb->chans[idx].irq)) {115 /* Clear mbox interrupt */116 writel_relaxed(1 << idx,117 mb->mbox_base + MAILBOX_B2A_STATUS);118 return IRQ_WAKE_THREAD;119 }120 }121 122 return IRQ_NONE;123}124 125static irqreturn_t rockchip_mbox_isr(int irq, void *dev_id)126{127 int idx;128 struct rockchip_mbox_msg *msg = NULL;129 struct rockchip_mbox *mb = (struct rockchip_mbox *)dev_id;130 131 for (idx = 0; idx < mb->mbox.num_chans; idx++) {132 if (irq != mb->chans[idx].irq)133 continue;134 135 msg = mb->chans[idx].msg;136 if (!msg) {137 dev_err(mb->mbox.dev,138 "Chan[%d]: B2A message is NULL\n", idx);139 break; /* spurious */140 }141 142 mbox_chan_received_data(&mb->mbox.chans[idx], msg);143 mb->chans[idx].msg = NULL;144 145 dev_dbg(mb->mbox.dev, "Chan[%d]: B2A message, cmd 0x%08x\n",146 idx, msg->cmd);147 148 break;149 }150 151 return IRQ_HANDLED;152}153 154static const struct rockchip_mbox_data rk3368_drv_data = {155 .num_chans = 4,156};157 158static const struct of_device_id rockchip_mbox_of_match[] = {159 { .compatible = "rockchip,rk3368-mailbox", .data = &rk3368_drv_data},160 { },161};162MODULE_DEVICE_TABLE(of, rockchip_mbox_of_match);163 164static int rockchip_mbox_probe(struct platform_device *pdev)165{166 struct rockchip_mbox *mb;167 const struct rockchip_mbox_data *drv_data;168 struct resource *res;169 int ret, irq, i;170 171 if (!pdev->dev.of_node)172 return -ENODEV;173 174 drv_data = (const struct rockchip_mbox_data *) device_get_match_data(&pdev->dev);175 176 mb = devm_kzalloc(&pdev->dev, sizeof(*mb), GFP_KERNEL);177 if (!mb)178 return -ENOMEM;179 180 mb->chans = devm_kcalloc(&pdev->dev, drv_data->num_chans,181 sizeof(*mb->chans), GFP_KERNEL);182 if (!mb->chans)183 return -ENOMEM;184 185 mb->mbox.chans = devm_kcalloc(&pdev->dev, drv_data->num_chans,186 sizeof(*mb->mbox.chans), GFP_KERNEL);187 if (!mb->mbox.chans)188 return -ENOMEM;189 190 platform_set_drvdata(pdev, mb);191 192 mb->mbox.dev = &pdev->dev;193 mb->mbox.num_chans = drv_data->num_chans;194 mb->mbox.ops = &rockchip_mbox_chan_ops;195 mb->mbox.txdone_irq = true;196 197 mb->mbox_base = devm_platform_get_and_ioremap_resource(pdev, 0, &res);198 if (IS_ERR(mb->mbox_base))199 return PTR_ERR(mb->mbox_base);200 201 /* Each channel has two buffers for A2B and B2A */202 mb->buf_size = (size_t)resource_size(res) / (drv_data->num_chans * 2);203 204 mb->pclk = devm_clk_get(&pdev->dev, "pclk_mailbox");205 if (IS_ERR(mb->pclk)) {206 ret = PTR_ERR(mb->pclk);207 dev_err(&pdev->dev, "failed to get pclk_mailbox clock: %d\n",208 ret);209 return ret;210 }211 212 ret = clk_prepare_enable(mb->pclk);213 if (ret) {214 dev_err(&pdev->dev, "failed to enable pclk: %d\n", ret);215 return ret;216 }217 218 for (i = 0; i < mb->mbox.num_chans; i++) {219 irq = platform_get_irq(pdev, i);220 if (irq < 0)221 return irq;222 223 ret = devm_request_threaded_irq(&pdev->dev, irq,224 rockchip_mbox_irq,225 rockchip_mbox_isr, IRQF_ONESHOT,226 dev_name(&pdev->dev), mb);227 if (ret < 0)228 return ret;229 230 mb->chans[i].idx = i;231 mb->chans[i].irq = irq;232 mb->chans[i].mb = mb;233 mb->chans[i].msg = NULL;234 }235 236 ret = devm_mbox_controller_register(&pdev->dev, &mb->mbox);237 if (ret < 0)238 dev_err(&pdev->dev, "Failed to register mailbox: %d\n", ret);239 240 return ret;241}242 243static struct platform_driver rockchip_mbox_driver = {244 .probe = rockchip_mbox_probe,245 .driver = {246 .name = "rockchip-mailbox",247 .of_match_table = rockchip_mbox_of_match,248 },249};250 251module_platform_driver(rockchip_mbox_driver);252 253MODULE_DESCRIPTION("Rockchip mailbox: communicate between CPU cores and MCU");254MODULE_AUTHOR("Addy Ke <addy.ke@rock-chips.com>");255MODULE_AUTHOR("Caesar Wang <wxt@rock-chips.com>");256