// SPDX-License-Identifier: GPL-2.0 /* * Copyright (c) 2018 Pengutronix, Oleksij Rempel <o.rempel@pengutronix.de> */ #include <linux/clk.h> #include <linux/firmware/imx/ipc.h> #include <linux/interrupt.h> #include <linux/io.h> #include <linux/iopoll.h> #include <linux/kernel.h> #include <linux/mailbox_controller.h> #include <linux/module.h> #include <linux/of_device.h> #include <linux/pm_runtime.h> #include <linux/slab.h> #define IMX_MU_xSR_GIPn(x) BIT(28 + (3 - (x))) #define IMX_MU_xSR_RFn(x) BIT(24 + (3 - (x))) #define IMX_MU_xSR_TEn(x) BIT(20 + (3 - (x))) #define IMX_MU_xSR_BRDIP BIT(9) /* General Purpose Interrupt Enable */ #define IMX_MU_xCR_GIEn(x) BIT(28 + (3 - (x))) /* Receive Interrupt Enable */ #define IMX_MU_xCR_RIEn(x) BIT(24 + (3 - (x))) /* Transmit Interrupt Enable */ #define IMX_MU_xCR_TIEn(x) BIT(20 + (3 - (x))) /* General Purpose Interrupt Request */ #define IMX_MU_xCR_GIRn(x) BIT(16 + (3 - (x))) #define IMX_MU_CHANS 16 /* TX0/RX0/RXDB[0-3] */ #define IMX_MU_SCU_CHANS 6 #define IMX_MU_CHAN_NAME_SIZE 20 enum imx_mu_chan_type { IMX_MU_TYPE_TX, /* Tx */ IMX_MU_TYPE_RX, /* Rx */ IMX_MU_TYPE_TXDB, /* Tx doorbell */ IMX_MU_TYPE_RXDB, /* Rx doorbell */ }; struct imx_sc_rpc_msg_max { struct imx_sc_rpc_msg hdr; u32 data[7]; }; struct imx_mu_con_priv { unsigned int idx; char irq_desc[IMX_MU_CHAN_NAME_SIZE]; enum imx_mu_chan_type type; struct mbox_chan *chan; struct tasklet_struct txdb_tasklet; }; struct imx_mu_priv { struct device *dev; void __iomem *base; spinlock_t xcr_lock; /* control register lock */ struct mbox_controller mbox; struct mbox_chan mbox_chans[IMX_MU_CHANS]; struct imx_mu_con_priv con_priv[IMX_MU_CHANS]; const struct imx_mu_dcfg *dcfg; struct clk *clk; int irq; u32 xcr; bool side_b; }; struct imx_mu_dcfg { int (*tx)(struct imx_mu_priv *priv, struct imx_mu_con_priv *cp, void *data); int (*rx)(struct imx_mu_priv *priv, struct imx_mu_con_priv *cp); void (*init)(struct imx_mu_priv *priv); u32 xTR[4]; /* Transmit Registers */ u32 xRR[4]; /* Receive Registers */ u32 xSR; /* Status Register */ u32 xCR; /* Control Register */ }; static struct imx_mu_priv *to_imx_mu_priv(struct mbox_controller *mbox) { return container_of(mbox, struct imx_mu_priv, mbox); } static void imx_mu_write(struct imx_mu_priv *priv, u32 val, u32 offs) { iowrite32(val, priv->base + offs); } static u32 imx_mu_read(struct imx_mu_priv *priv, u32 offs) { return ioread32(priv->base + offs); } static u32 imx_mu_xcr_rmw(struct imx_mu_priv *priv, u32 set, u32 clr) { unsigned long flags; u32 val; spin_lock_irqsave(&priv->xcr_lock, flags); val = imx_mu_read(priv, priv->dcfg->xCR); val &= ~clr; val |= set; imx_mu_write(priv, val, priv->dcfg->xCR); spin_unlock_irqrestore(&priv->xcr_lock, flags); return val; } static int imx_mu_generic_tx(struct imx_mu_priv *priv, struct imx_mu_con_priv *cp, void *data) { u32 *arg = data; switch (cp->type) { case IMX_MU_TYPE_TX: imx_mu_write(priv, *arg, priv->dcfg->xTR[cp->idx]); imx_mu_xcr_rmw(priv, IMX_MU_xCR_TIEn(cp->idx), 0); break; case IMX_MU_TYPE_TXDB: imx_mu_xcr_rmw(priv, IMX_MU_xCR_GIRn(cp->idx), 0); tasklet_schedule(&cp->txdb_tasklet); break; default: dev_warn_ratelimited(priv->dev, "Send data on wrong channel type: %d\n", cp->type); return -EINVAL; } return 0; } static int imx_mu_generic_rx(struct imx_mu_priv *priv, struct imx_mu_con_priv *cp) { u32 dat; dat = imx_mu_read(priv, priv->dcfg->xRR[cp->idx]); mbox_chan_received_data(cp->chan, (void *)&dat); return 0; } static int imx_mu_scu_tx(struct imx_mu_priv *priv, struct imx_mu_con_priv *cp, void *data) { struct imx_sc_rpc_msg_max *msg = data; u32 *arg = data; int i, ret; u32 xsr; switch (cp->type) { case IMX_MU_TYPE_TX: /* * msg->hdr.size specifies the number of u32 words while * sizeof yields bytes. */ if (msg->hdr.size > sizeof(*msg) / 4) { /* * The real message size can be different to * struct imx_sc_rpc_msg_max size */ dev_err(priv->dev, "Maximal message size (%zu bytes) exceeded on TX; got: %i bytes\n", sizeof(*msg), msg->hdr.size << 2); return -EINVAL; } for (i = 0; i < 4 && i < msg->hdr.size; i++) imx_mu_write(priv, *arg++, priv->dcfg->xTR[i % 4]); for (; i < msg->hdr.size; i++) { ret = readl_poll_timeout(priv->base + priv->dcfg->xSR, xsr, xsr & IMX_MU_xSR_TEn(i % 4), 0, 100); if (ret) { dev_err(priv->dev, "Send data index: %d timeout\n", i); return ret; } imx_mu_write(priv, *arg++, priv->dcfg->xTR[i % 4]); } imx_mu_xcr_rmw(priv, IMX_MU_xCR_TIEn(cp->idx), 0); break; default: dev_warn_ratelimited(priv->dev, "Send data on wrong channel type: %d\n", cp->type); return -EINVAL; } return 0; } static int imx_mu_scu_rx(struct imx_mu_priv *priv, struct imx_mu_con_priv *cp) { struct imx_sc_rpc_msg_max msg; u32 *data = (u32 *)&msg; int i, ret; u32 xsr; imx_mu_xcr_rmw(priv, 0, IMX_MU_xCR_RIEn(0)); *data++ = imx_mu_read(priv, priv->dcfg->xRR[0]); if (msg.hdr.size > sizeof(msg) / 4) { dev_err(priv->dev, "Maximal message size (%zu bytes) exceeded on RX; got: %i bytes\n", sizeof(msg), msg.hdr.size << 2); return -EINVAL; } for (i = 1; i < msg.hdr.size; i++) { ret = readl_poll_timeout(priv->base + priv->dcfg->xSR, xsr, xsr & IMX_MU_xSR_RFn(i % 4), 0, 100); if (ret) { dev_err(priv->dev, "timeout read idx %d\n", i); return ret; } *data++ = imx_mu_read(priv, priv->dcfg->xRR[i % 4]); } imx_mu_xcr_rmw(priv, IMX_MU_xCR_RIEn(0), 0); mbox_chan_received_data(cp->chan, (void *)&msg); return 0; } static void imx_mu_txdb_tasklet(unsigned long data) { struct imx_mu_con_priv *cp = (struct imx_mu_con_priv *)data; mbox_chan_txdone(cp->chan, 0); } static irqreturn_t imx_mu_isr(int irq, void *p) { struct mbox_chan *chan = p; struct imx_mu_priv *priv = to_imx_mu_priv(chan->mbox); struct imx_mu_con_priv *cp = chan->con_priv; u32 val, ctrl; ctrl = imx_mu_read(priv, priv->dcfg->xCR); val = imx_mu_read(priv, priv->dcfg->xSR); switch (cp->type) { case IMX_MU_TYPE_TX: val &= IMX_MU_xSR_TEn(cp->idx) & (ctrl & IMX_MU_xCR_TIEn(cp->idx)); break; case IMX_MU_TYPE_RX: val &= IMX_MU_xSR_RFn(cp->idx) & (ctrl & IMX_MU_xCR_RIEn(cp->idx)); break; case IMX_MU_TYPE_RXDB: val &= IMX_MU_xSR_GIPn(cp->idx) & (ctrl & IMX_MU_xCR_GIEn(cp->idx)); break; default: break; } if (!val) return IRQ_NONE; if (val == IMX_MU_xSR_TEn(cp->idx)) { imx_mu_xcr_rmw(priv, 0, IMX_MU_xCR_TIEn(cp->idx)); mbox_chan_txdone(chan, 0); } else if (val == IMX_MU_xSR_RFn(cp->idx)) { priv->dcfg->rx(priv, cp); } else if (val == IMX_MU_xSR_GIPn(cp->idx)) { imx_mu_write(priv, IMX_MU_xSR_GIPn(cp->idx), priv->dcfg->xSR); mbox_chan_received_data(chan, NULL); } else { dev_warn_ratelimited(priv->dev, "Not handled interrupt\n"); return IRQ_NONE; } return IRQ_HANDLED; } static int imx_mu_send_data(struct mbox_chan *chan, void *data) { struct imx_mu_priv *priv = to_imx_mu_priv(chan->mbox); struct imx_mu_con_priv *cp = chan->con_priv; return priv->dcfg->tx(priv, cp, data); } static int imx_mu_startup(struct mbox_chan *chan) { struct imx_mu_priv *priv = to_imx_mu_priv(chan->mbox); struct imx_mu_con_priv *cp = chan->con_priv; unsigned long irq_flag = IRQF_SHARED; int ret; pm_runtime_get_sync(priv->dev); if (cp->type == IMX_MU_TYPE_TXDB) { /* Tx doorbell don't have ACK support */ tasklet_init(&cp->txdb_tasklet, imx_mu_txdb_tasklet, (unsigned long)cp); return 0; } /* IPC MU should be with IRQF_NO_SUSPEND set */ if (!priv->dev->pm_domain) irq_flag |= IRQF_NO_SUSPEND; ret = request_irq(priv->irq, imx_mu_isr, irq_flag, cp->irq_desc, chan); if (ret) { dev_err(priv->dev, "Unable to acquire IRQ %d\n", priv->irq); return ret; } switch (cp->type) { case IMX_MU_TYPE_RX: imx_mu_xcr_rmw(priv, IMX_MU_xCR_RIEn(cp->idx), 0); break; case IMX_MU_TYPE_RXDB: imx_mu_xcr_rmw(priv, IMX_MU_xCR_GIEn(cp->idx), 0); break; default: break; } return 0; } static void imx_mu_shutdown(struct mbox_chan *chan) { struct imx_mu_priv *priv = to_imx_mu_priv(chan->mbox); struct imx_mu_con_priv *cp = chan->con_priv; if (cp->type == IMX_MU_TYPE_TXDB) { tasklet_kill(&cp->txdb_tasklet); pm_runtime_put_sync(priv->dev); return; } switch (cp->type) { case IMX_MU_TYPE_TX: imx_mu_xcr_rmw(priv, 0, IMX_MU_xCR_TIEn(cp->idx)); break; case IMX_MU_TYPE_RX: imx_mu_xcr_rmw(priv, 0, IMX_MU_xCR_RIEn(cp->idx)); break; case IMX_MU_TYPE_RXDB: imx_mu_xcr_rmw(priv, 0, IMX_MU_xCR_GIEn(cp->idx)); break; default: break; } free_irq(priv->irq, chan); pm_runtime_put_sync(priv->dev); } static const struct mbox_chan_ops imx_mu_ops = { .send_data = imx_mu_send_data, .startup = imx_mu_startup, .shutdown = imx_mu_shutdown, }; static struct mbox_chan *imx_mu_scu_xlate(struct mbox_controller *mbox, const struct of_phandle_args *sp) { u32 type, idx, chan; if (sp->args_count != 2) { dev_err(mbox->dev, "Invalid argument count %d\n", sp->args_count); return ERR_PTR(-EINVAL); } type = sp->args[0]; /* channel type */ idx = sp->args[1]; /* index */ switch (type) { case IMX_MU_TYPE_TX: case IMX_MU_TYPE_RX: if (idx != 0) dev_err(mbox->dev, "Invalid chan idx: %d\n", idx); chan = type; break; case IMX_MU_TYPE_RXDB: chan = 2 + idx; break; default: dev_err(mbox->dev, "Invalid chan type: %d\n", type); return ERR_PTR(-EINVAL); } if (chan >= mbox->num_chans) { dev_err(mbox->dev, "Not supported channel number: %d. (type: %d, idx: %d)\n", chan, type, idx); return ERR_PTR(-EINVAL); } return &mbox->chans[chan]; } static struct mbox_chan * imx_mu_xlate(struct mbox_controller *mbox, const struct of_phandle_args *sp) { u32 type, idx, chan; if (sp->args_count != 2) { dev_err(mbox->dev, "Invalid argument count %d\n", sp->args_count); return ERR_PTR(-EINVAL); } type = sp->args[0]; /* channel type */ idx = sp->args[1]; /* index */ chan = type * 4 + idx; if (chan >= mbox->num_chans) { dev_err(mbox->dev, "Not supported channel number: %d. (type: %d, idx: %d)\n", chan, type, idx); return ERR_PTR(-EINVAL); } return &mbox->chans[chan]; } static void imx_mu_init_generic(struct imx_mu_priv *priv) { unsigned int i; for (i = 0; i < IMX_MU_CHANS; i++) { struct imx_mu_con_priv *cp = &priv->con_priv[i]; cp->idx = i % 4; cp->type = i >> 2; cp->chan = &priv->mbox_chans[i]; priv->mbox_chans[i].con_priv = cp; snprintf(cp->irq_desc, sizeof(cp->irq_desc), "imx_mu_chan[%i-%i]", cp->type, cp->idx); } priv->mbox.num_chans = IMX_MU_CHANS; priv->mbox.of_xlate = imx_mu_xlate; if (priv->side_b) return; /* Set default MU configuration */ imx_mu_write(priv, 0, priv->dcfg->xCR); } static void imx_mu_init_scu(struct imx_mu_priv *priv) { unsigned int i; for (i = 0; i < IMX_MU_SCU_CHANS; i++) { struct imx_mu_con_priv *cp = &priv->con_priv[i]; cp->idx = i < 2 ? 0 : i - 2; cp->type = i < 2 ? i : IMX_MU_TYPE_RXDB; cp->chan = &priv->mbox_chans[i]; priv->mbox_chans[i].con_priv = cp; snprintf(cp->irq_desc, sizeof(cp->irq_desc), "imx_mu_chan[%i-%i]", cp->type, cp->idx); } priv->mbox.num_chans = IMX_MU_SCU_CHANS; priv->mbox.of_xlate = imx_mu_scu_xlate; /* Set default MU configuration */ imx_mu_write(priv, 0, priv->dcfg->xCR); } static int imx_mu_probe(struct platform_device *pdev) { struct device *dev = &pdev->dev; struct device_node *np = dev->of_node; struct imx_mu_priv *priv; const struct imx_mu_dcfg *dcfg; int ret; priv = devm_kzalloc(dev, sizeof(*priv), GFP_KERNEL); if (!priv) return -ENOMEM; priv->dev = dev; priv->base = devm_platform_ioremap_resource(pdev, 0); if (IS_ERR(priv->base)) return PTR_ERR(priv->base); priv->irq = platform_get_irq(pdev, 0); if (priv->irq < 0) return priv->irq; dcfg = of_device_get_match_data(dev); if (!dcfg) return -EINVAL; priv->dcfg = dcfg; priv->clk = devm_clk_get(dev, NULL); if (IS_ERR(priv->clk)) { if (PTR_ERR(priv->clk) != -ENOENT) return PTR_ERR(priv->clk); priv->clk = NULL; } ret = clk_prepare_enable(priv->clk); if (ret) { dev_err(dev, "Failed to enable clock\n"); return ret; } priv->side_b = of_property_read_bool(np, "fsl,mu-side-b"); priv->dcfg->init(priv); spin_lock_init(&priv->xcr_lock); priv->mbox.dev = dev; priv->mbox.ops = &imx_mu_ops; priv->mbox.chans = priv->mbox_chans; priv->mbox.txdone_irq = true; platform_set_drvdata(pdev, priv); ret = devm_mbox_controller_register(dev, &priv->mbox); if (ret) { clk_disable_unprepare(priv->clk); return ret; } pm_runtime_enable(dev); ret = pm_runtime_get_sync(dev); if (ret < 0) { pm_runtime_put_noidle(dev); goto disable_runtime_pm; } ret = pm_runtime_put_sync(dev); if (ret < 0) goto disable_runtime_pm; clk_disable_unprepare(priv->clk); return 0; disable_runtime_pm: pm_runtime_disable(dev); clk_disable_unprepare(priv->clk); return ret; } static int imx_mu_remove(struct platform_device *pdev) { struct imx_mu_priv *priv = platform_get_drvdata(pdev); pm_runtime_disable(priv->dev); return 0; } static const struct imx_mu_dcfg imx_mu_cfg_imx6sx = { .tx = imx_mu_generic_tx, .rx = imx_mu_generic_rx, .init = imx_mu_init_generic, .xTR = {0x0, 0x4, 0x8, 0xc}, .xRR = {0x10, 0x14, 0x18, 0x1c}, .xSR = 0x20, .xCR = 0x24, }; static const struct imx_mu_dcfg imx_mu_cfg_imx7ulp = { .tx = imx_mu_generic_tx, .rx = imx_mu_generic_rx, .init = imx_mu_init_generic, .xTR = {0x20, 0x24, 0x28, 0x2c}, .xRR = {0x40, 0x44, 0x48, 0x4c}, .xSR = 0x60, .xCR = 0x64, }; static const struct imx_mu_dcfg imx_mu_cfg_imx8_scu = { .tx = imx_mu_scu_tx, .rx = imx_mu_scu_rx, .init = imx_mu_init_scu, .xTR = {0x0, 0x4, 0x8, 0xc}, .xRR = {0x10, 0x14, 0x18, 0x1c}, .xSR = 0x20, .xCR = 0x24, }; static const struct of_device_id imx_mu_dt_ids[] = { { .compatible = "fsl,imx7ulp-mu", .data = &imx_mu_cfg_imx7ulp }, { .compatible = "fsl,imx6sx-mu", .data = &imx_mu_cfg_imx6sx }, { .compatible = "fsl,imx8-mu-scu", .data = &imx_mu_cfg_imx8_scu }, { }, }; MODULE_DEVICE_TABLE(of, imx_mu_dt_ids); static int __maybe_unused imx_mu_suspend_noirq(struct device *dev) { struct imx_mu_priv *priv = dev_get_drvdata(dev); if (!priv->clk) priv->xcr = imx_mu_read(priv, priv->dcfg->xCR); return 0; } static int __maybe_unused imx_mu_resume_noirq(struct device *dev) { struct imx_mu_priv *priv = dev_get_drvdata(dev); /* * ONLY restore MU when context lost, the TIE could * be set during noirq resume as there is MU data * communication going on, and restore the saved * value will overwrite the TIE and cause MU data * send failed, may lead to system freeze. This issue * is observed by testing freeze mode suspend. */ if (!imx_mu_read(priv, priv->dcfg->xCR) && !priv->clk) imx_mu_write(priv, priv->xcr, priv->dcfg->xCR); return 0; } static int __maybe_unused imx_mu_runtime_suspend(struct device *dev) { struct imx_mu_priv *priv = dev_get_drvdata(dev); clk_disable_unprepare(priv->clk); return 0; } static int __maybe_unused imx_mu_runtime_resume(struct device *dev) { struct imx_mu_priv *priv = dev_get_drvdata(dev); int ret; ret = clk_prepare_enable(priv->clk); if (ret) dev_err(dev, "failed to enable clock\n"); return ret; } static const struct dev_pm_ops imx_mu_pm_ops = { SET_NOIRQ_SYSTEM_SLEEP_PM_OPS(imx_mu_suspend_noirq, imx_mu_resume_noirq) SET_RUNTIME_PM_OPS(imx_mu_runtime_suspend, imx_mu_runtime_resume, NULL) }; static struct platform_driver imx_mu_driver = { .probe = imx_mu_probe, .remove = imx_mu_remove, .driver = { .name = "imx_mu", .of_match_table = imx_mu_dt_ids, .pm = &imx_mu_pm_ops, }, }; module_platform_driver(imx_mu_driver); MODULE_AUTHOR("Oleksij Rempel <o.rempel@pengutronix.de>"); MODULE_DESCRIPTION("Message Unit driver for i.MX"); MODULE_LICENSE("GPL v2");