/* * Copyright (c) 2015, Fuzhou Rockchip Electronics Co., Ltd * * This program is free software; you can redistribute it and/or modify it * under the terms and conditions of the GNU General Public License, * version 2, as published by the Free Software Foundation. * * This program is distributed in the hope it will be useful, but WITHOUT * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for * more details. */ #include <linux/clk.h> #include <linux/interrupt.h> #include <linux/io.h> #include <linux/kernel.h> #include <linux/mailbox_controller.h> #include <linux/module.h> #include <linux/of_device.h> #include <linux/platform_device.h> #define MAILBOX_A2B_INTEN 0x00 #define MAILBOX_A2B_STATUS 0x04 #define MAILBOX_A2B_CMD(x) (0x08 + (x) * 8) #define MAILBOX_A2B_DAT(x) (0x0c + (x) * 8) #define MAILBOX_B2A_INTEN 0x28 #define MAILBOX_B2A_STATUS 0x2C #define MAILBOX_B2A_CMD(x) (0x30 + (x) * 8) #define MAILBOX_B2A_DAT(x) (0x34 + (x) * 8) struct rockchip_mbox_msg { u32 cmd; int rx_size; }; struct rockchip_mbox_data { int num_chans; }; struct rockchip_mbox_chan { int idx; int irq; struct rockchip_mbox_msg *msg; struct rockchip_mbox *mb; }; struct rockchip_mbox { struct mbox_controller mbox; struct clk *pclk; void __iomem *mbox_base; /* The maximum size of buf for each channel */ u32 buf_size; struct rockchip_mbox_chan *chans; }; static int rockchip_mbox_send_data(struct mbox_chan *chan, void *data) { struct rockchip_mbox *mb = dev_get_drvdata(chan->mbox->dev); struct rockchip_mbox_msg *msg = data; struct rockchip_mbox_chan *chans = mb->chans; if (!msg) return -EINVAL; if (msg->rx_size > mb->buf_size) { dev_err(mb->mbox.dev, "Transmit size over buf size(%d)\n", mb->buf_size); return -EINVAL; } dev_dbg(mb->mbox.dev, "Chan[%d]: A2B message, cmd 0x%08x\n", chans->idx, msg->cmd); mb->chans[chans->idx].msg = msg; writel_relaxed(msg->cmd, mb->mbox_base + MAILBOX_A2B_CMD(chans->idx)); writel_relaxed(msg->rx_size, mb->mbox_base + MAILBOX_A2B_DAT(chans->idx)); return 0; } static int rockchip_mbox_startup(struct mbox_chan *chan) { struct rockchip_mbox *mb = dev_get_drvdata(chan->mbox->dev); /* Enable all B2A interrupts */ writel_relaxed((1 << mb->mbox.num_chans) - 1, mb->mbox_base + MAILBOX_B2A_INTEN); return 0; } static void rockchip_mbox_shutdown(struct mbox_chan *chan) { struct rockchip_mbox *mb = dev_get_drvdata(chan->mbox->dev); struct rockchip_mbox_chan *chans = mb->chans; /* Disable all B2A interrupts */ writel_relaxed(0, mb->mbox_base + MAILBOX_B2A_INTEN); mb->chans[chans->idx].msg = NULL; } static const struct mbox_chan_ops rockchip_mbox_chan_ops = { .send_data = rockchip_mbox_send_data, .startup = rockchip_mbox_startup, .shutdown = rockchip_mbox_shutdown, }; static irqreturn_t rockchip_mbox_irq(int irq, void *dev_id) { int idx; struct rockchip_mbox *mb = (struct rockchip_mbox *)dev_id; u32 status = readl_relaxed(mb->mbox_base + MAILBOX_B2A_STATUS); for (idx = 0; idx < mb->mbox.num_chans; idx++) { if ((status & (1 << idx)) && (irq == mb->chans[idx].irq)) { /* Clear mbox interrupt */ writel_relaxed(1 << idx, mb->mbox_base + MAILBOX_B2A_STATUS); return IRQ_WAKE_THREAD; } } return IRQ_NONE; } static irqreturn_t rockchip_mbox_isr(int irq, void *dev_id) { int idx; struct rockchip_mbox_msg *msg = NULL; struct rockchip_mbox *mb = (struct rockchip_mbox *)dev_id; for (idx = 0; idx < mb->mbox.num_chans; idx++) { if (irq != mb->chans[idx].irq) continue; msg = mb->chans[idx].msg; if (!msg) { dev_err(mb->mbox.dev, "Chan[%d]: B2A message is NULL\n", idx); break; /* spurious */ } mbox_chan_received_data(&mb->mbox.chans[idx], msg); mb->chans[idx].msg = NULL; dev_dbg(mb->mbox.dev, "Chan[%d]: B2A message, cmd 0x%08x\n", idx, msg->cmd); break; } return IRQ_HANDLED; } static const struct rockchip_mbox_data rk3368_drv_data = { .num_chans = 4, }; static const struct of_device_id rockchip_mbox_of_match[] = { { .compatible = "rockchip,rk3368-mailbox", .data = &rk3368_drv_data}, { }, }; MODULE_DEVICE_TABLE(of, rockchp_mbox_of_match); static int rockchip_mbox_probe(struct platform_device *pdev) { struct rockchip_mbox *mb; const struct of_device_id *match; const struct rockchip_mbox_data *drv_data; struct resource *res; int ret, irq, i; if (!pdev->dev.of_node) return -ENODEV; match = of_match_node(rockchip_mbox_of_match, pdev->dev.of_node); drv_data = (const struct rockchip_mbox_data *)match->data; mb = devm_kzalloc(&pdev->dev, sizeof(*mb), GFP_KERNEL); if (!mb) return -ENOMEM; mb->chans = devm_kcalloc(&pdev->dev, drv_data->num_chans, sizeof(*mb->chans), GFP_KERNEL); if (!mb->chans) return -ENOMEM; mb->mbox.chans = devm_kcalloc(&pdev->dev, drv_data->num_chans, sizeof(*mb->mbox.chans), GFP_KERNEL); if (!mb->mbox.chans) return -ENOMEM; platform_set_drvdata(pdev, mb); mb->mbox.dev = &pdev->dev; mb->mbox.num_chans = drv_data->num_chans; mb->mbox.ops = &rockchip_mbox_chan_ops; mb->mbox.txdone_irq = true; res = platform_get_resource(pdev, IORESOURCE_MEM, 0); if (!res) return -ENODEV; mb->mbox_base = devm_ioremap_resource(&pdev->dev, res); if (IS_ERR(mb->mbox_base)) return PTR_ERR(mb->mbox_base); /* Each channel has two buffers for A2B and B2A */ mb->buf_size = (size_t)resource_size(res) / (drv_data->num_chans * 2); mb->pclk = devm_clk_get(&pdev->dev, "pclk_mailbox"); if (IS_ERR(mb->pclk)) { ret = PTR_ERR(mb->pclk); dev_err(&pdev->dev, "failed to get pclk_mailbox clock: %d\n", ret); return ret; } ret = clk_prepare_enable(mb->pclk); if (ret) { dev_err(&pdev->dev, "failed to enable pclk: %d\n", ret); return ret; } for (i = 0; i < mb->mbox.num_chans; i++) { irq = platform_get_irq(pdev, i); if (irq < 0) return irq; ret = devm_request_threaded_irq(&pdev->dev, irq, rockchip_mbox_irq, rockchip_mbox_isr, IRQF_ONESHOT, dev_name(&pdev->dev), mb); if (ret < 0) return ret; mb->chans[i].idx = i; mb->chans[i].irq = irq; mb->chans[i].mb = mb; mb->chans[i].msg = NULL; } ret = mbox_controller_register(&mb->mbox); if (ret < 0) dev_err(&pdev->dev, "Failed to register mailbox: %d\n", ret); return ret; } static int rockchip_mbox_remove(struct platform_device *pdev) { struct rockchip_mbox *mb = platform_get_drvdata(pdev); if (!mb) return -EINVAL; mbox_controller_unregister(&mb->mbox); return 0; } static struct platform_driver rockchip_mbox_driver = { .probe = rockchip_mbox_probe, .remove = rockchip_mbox_remove, .driver = { .name = "rockchip-mailbox", .of_match_table = of_match_ptr(rockchip_mbox_of_match), }, }; module_platform_driver(rockchip_mbox_driver); MODULE_LICENSE("GPL v2"); MODULE_DESCRIPTION("Rockchip mailbox: communicate between CPU cores and MCU"); MODULE_AUTHOR("Addy Ke <addy.ke@rock-chips.com>"); MODULE_AUTHOR("Caesar Wang <wxt@rock-chips.com>");