diff options
Diffstat (limited to 'drivers/mailbox/mailbox-th1520.c')
| -rw-r--r-- | drivers/mailbox/mailbox-th1520.c | 597 |
1 files changed, 597 insertions, 0 deletions
diff --git a/drivers/mailbox/mailbox-th1520.c b/drivers/mailbox/mailbox-th1520.c new file mode 100644 index 000000000000..4e84640ac3b8 --- /dev/null +++ b/drivers/mailbox/mailbox-th1520.c @@ -0,0 +1,597 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * Copyright (C) 2021 Alibaba Group Holding Limited. + */ + +#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> +#include <linux/slab.h> + +/* Status Register */ +#define TH_1520_MBOX_STA 0x0 +#define TH_1520_MBOX_CLR 0x4 +#define TH_1520_MBOX_MASK 0xc + +/* Transmit/receive data register: + * INFO0 ~ INFO6 + */ +#define TH_1520_MBOX_INFO_NUM 8 +#define TH_1520_MBOX_DATA_INFO_NUM 7 +#define TH_1520_MBOX_INFO0 0x14 +/* Transmit ack register: INFO7 */ +#define TH_1520_MBOX_INFO7 0x30 + +/* Generate remote icu IRQ Register */ +#define TH_1520_MBOX_GEN 0x10 +#define TH_1520_MBOX_GEN_RX_DATA BIT(6) +#define TH_1520_MBOX_GEN_TX_ACK BIT(7) + +#define TH_1520_MBOX_CHAN_RES_SIZE 0x1000 +#define TH_1520_MBOX_CHANS 4 +#define TH_1520_MBOX_CHAN_NAME_SIZE 20 + +#define TH_1520_MBOX_ACK_MAGIC 0xdeadbeaf + +#ifdef CONFIG_PM_SLEEP +/* store MBOX context across system-wide suspend/resume transitions */ +struct th1520_mbox_context { + u32 intr_mask[TH_1520_MBOX_CHANS - 1]; +}; +#endif + +enum th1520_mbox_icu_cpu_id { + TH_1520_MBOX_ICU_KERNEL_CPU0, /* 910T */ + TH_1520_MBOX_ICU_CPU1, /* 902 */ + TH_1520_MBOX_ICU_CPU2, /* 906 */ + TH_1520_MBOX_ICU_CPU3, /* 910R */ +}; + +struct th1520_mbox_con_priv { + enum th1520_mbox_icu_cpu_id idx; + void __iomem *comm_local_base; + void __iomem *comm_remote_base; + char irq_desc[TH_1520_MBOX_CHAN_NAME_SIZE]; + struct mbox_chan *chan; +}; + +struct th1520_mbox_priv { + struct device *dev; + void __iomem *local_icu[TH_1520_MBOX_CHANS]; + void __iomem *remote_icu[TH_1520_MBOX_CHANS - 1]; + void __iomem *cur_cpu_ch_base; + spinlock_t mbox_lock; /* control register lock */ + + struct mbox_controller mbox; + struct mbox_chan mbox_chans[TH_1520_MBOX_CHANS]; + struct clk_bulk_data clocks[TH_1520_MBOX_CHANS]; + struct th1520_mbox_con_priv con_priv[TH_1520_MBOX_CHANS]; + int irq; +#ifdef CONFIG_PM_SLEEP + struct th1520_mbox_context *ctx; +#endif +}; + +static struct th1520_mbox_priv * +to_th1520_mbox_priv(struct mbox_controller *mbox) +{ + return container_of(mbox, struct th1520_mbox_priv, mbox); +} + +static void th1520_mbox_write(struct th1520_mbox_priv *priv, u32 val, u32 offs) +{ + iowrite32(val, priv->cur_cpu_ch_base + offs); +} + +static u32 th1520_mbox_read(struct th1520_mbox_priv *priv, u32 offs) +{ + return ioread32(priv->cur_cpu_ch_base + offs); +} + +static u32 th1520_mbox_rmw(struct th1520_mbox_priv *priv, u32 off, u32 set, + u32 clr) +{ + unsigned long flags; + u32 val; + + spin_lock_irqsave(&priv->mbox_lock, flags); + val = th1520_mbox_read(priv, off); + val &= ~clr; + val |= set; + th1520_mbox_write(priv, val, off); + spin_unlock_irqrestore(&priv->mbox_lock, flags); + + return val; +} + +static void th1520_mbox_chan_write(struct th1520_mbox_con_priv *cp, u32 val, + u32 offs, bool is_remote) +{ + if (is_remote) + iowrite32(val, cp->comm_remote_base + offs); + else + iowrite32(val, cp->comm_local_base + offs); +} + +static u32 th1520_mbox_chan_read(struct th1520_mbox_con_priv *cp, u32 offs, + bool is_remote) +{ + if (is_remote) + return ioread32(cp->comm_remote_base + offs); + else + return ioread32(cp->comm_local_base + offs); +} + +static void th1520_mbox_chan_rmw(struct th1520_mbox_con_priv *cp, u32 off, + u32 set, u32 clr, bool is_remote) +{ + struct th1520_mbox_priv *priv = to_th1520_mbox_priv(cp->chan->mbox); + unsigned long flags; + u32 val; + + spin_lock_irqsave(&priv->mbox_lock, flags); + val = th1520_mbox_chan_read(cp, off, is_remote); + val &= ~clr; + val |= set; + th1520_mbox_chan_write(cp, val, off, is_remote); + spin_unlock_irqrestore(&priv->mbox_lock, flags); +} + +static void th1520_mbox_chan_rd_data(struct th1520_mbox_con_priv *cp, + void *data, bool is_remote) +{ + u32 off = TH_1520_MBOX_INFO0; + u32 *arg = data; + u32 i; + + /* read info0 ~ info6, totally 28 bytes + * requires data memory size is 28 bytes + */ + for (i = 0; i < TH_1520_MBOX_DATA_INFO_NUM; i++) { + *arg = th1520_mbox_chan_read(cp, off, is_remote); + off += 4; + arg++; + } +} + +static void th1520_mbox_chan_wr_data(struct th1520_mbox_con_priv *cp, + void *data, bool is_remote) +{ + u32 off = TH_1520_MBOX_INFO0; + u32 *arg = data; + u32 i; + + /* write info0 ~ info6, totally 28 bytes + * requires data memory is 28 bytes valid data + */ + for (i = 0; i < TH_1520_MBOX_DATA_INFO_NUM; i++) { + th1520_mbox_chan_write(cp, *arg, off, is_remote); + off += 4; + arg++; + } +} + +static void th1520_mbox_chan_wr_ack(struct th1520_mbox_con_priv *cp, void *data, + bool is_remote) +{ + u32 off = TH_1520_MBOX_INFO7; + u32 *arg = data; + + th1520_mbox_chan_write(cp, *arg, off, is_remote); +} + +static int th1520_mbox_chan_id_to_mapbit(struct th1520_mbox_con_priv *cp) +{ + int mapbit = 0; + int i; + + for (i = 0; i < TH_1520_MBOX_CHANS; i++) { + if (i == cp->idx) + return mapbit; + + if (i != TH_1520_MBOX_ICU_KERNEL_CPU0) + mapbit++; + } + + if (i == TH_1520_MBOX_CHANS) + dev_err(cp->chan->mbox->dev, "convert to mapbit failed\n"); + + return 0; +} + +static irqreturn_t th1520_mbox_isr(int irq, void *p) +{ + struct mbox_chan *chan = p; + struct th1520_mbox_priv *priv = to_th1520_mbox_priv(chan->mbox); + struct th1520_mbox_con_priv *cp = chan->con_priv; + int mapbit = th1520_mbox_chan_id_to_mapbit(cp); + u32 sta, dat[TH_1520_MBOX_DATA_INFO_NUM]; + u32 ack_magic = TH_1520_MBOX_ACK_MAGIC; + u32 info0_data, info7_data; + + sta = th1520_mbox_read(priv, TH_1520_MBOX_STA); + if (!(sta & BIT(mapbit))) + return IRQ_NONE; + + /* clear chan irq bit in STA register */ + th1520_mbox_rmw(priv, TH_1520_MBOX_CLR, BIT(mapbit), 0); + + /* info0 is the protocol word, should not be zero! */ + info0_data = th1520_mbox_chan_read(cp, TH_1520_MBOX_INFO0, false); + if (info0_data) { + /* read info0~info6 data */ + th1520_mbox_chan_rd_data(cp, dat, false); + + /* clear local info0 */ + th1520_mbox_chan_write(cp, 0x0, TH_1520_MBOX_INFO0, false); + + /* notify remote cpu */ + th1520_mbox_chan_wr_ack(cp, &ack_magic, true); + /* CPU1 902/906 use polling mode to monitor info7 */ + if (cp->idx != TH_1520_MBOX_ICU_CPU1 && + cp->idx != TH_1520_MBOX_ICU_CPU2) + th1520_mbox_chan_rmw(cp, TH_1520_MBOX_GEN, + TH_1520_MBOX_GEN_TX_ACK, 0, true); + + /* transfer the data to client */ + mbox_chan_received_data(chan, (void *)dat); + } + + /* info7 magic value mean the real ack signal, not generate bit7 */ + info7_data = th1520_mbox_chan_read(cp, TH_1520_MBOX_INFO7, false); + if (info7_data == TH_1520_MBOX_ACK_MAGIC) { + /* clear local info7 */ + th1520_mbox_chan_write(cp, 0x0, TH_1520_MBOX_INFO7, false); + + /* notify framework the last TX has completed */ + mbox_chan_txdone(chan, 0); + } + + if (!info0_data && !info7_data) + return IRQ_NONE; + + return IRQ_HANDLED; +} + +static int th1520_mbox_send_data(struct mbox_chan *chan, void *data) +{ + struct th1520_mbox_con_priv *cp = chan->con_priv; + + th1520_mbox_chan_wr_data(cp, data, true); + th1520_mbox_chan_rmw(cp, TH_1520_MBOX_GEN, TH_1520_MBOX_GEN_RX_DATA, 0, + true); + return 0; +} + +static int th1520_mbox_startup(struct mbox_chan *chan) +{ + struct th1520_mbox_priv *priv = to_th1520_mbox_priv(chan->mbox); + struct th1520_mbox_con_priv *cp = chan->con_priv; + u32 data[8] = {}; + int mask_bit; + int ret; + + /* clear local and remote generate and info0~info7 */ + th1520_mbox_chan_rmw(cp, TH_1520_MBOX_GEN, 0x0, 0xff, true); + th1520_mbox_chan_rmw(cp, TH_1520_MBOX_GEN, 0x0, 0xff, false); + th1520_mbox_chan_wr_ack(cp, &data[7], true); + th1520_mbox_chan_wr_ack(cp, &data[7], false); + th1520_mbox_chan_wr_data(cp, &data[0], true); + th1520_mbox_chan_wr_data(cp, &data[0], false); + + /* enable the chan mask */ + mask_bit = th1520_mbox_chan_id_to_mapbit(cp); + th1520_mbox_rmw(priv, TH_1520_MBOX_MASK, BIT(mask_bit), 0); + + /* + * Mixing devm_ managed resources with manual IRQ handling is generally + * discouraged due to potential complexities with resource management, + * especially when dealing with shared interrupts. However, in this case, + * the approach is safe and effective because: + * + * 1. Each mailbox channel requests its IRQ within the .startup() callback + * and frees it within the .shutdown() callback. + * 2. During device unbinding, the devm_ managed mailbox controller first + * iterates through all channels, ensuring that their IRQs are freed before + * any other devm_ resources are released. + * + * This ordering guarantees that no interrupts can be triggered from the device + * while it is being unbound, preventing race conditions and ensuring system + * stability. + */ + ret = request_irq(priv->irq, th1520_mbox_isr, + IRQF_SHARED | IRQF_NO_SUSPEND, cp->irq_desc, chan); + if (ret) { + dev_err(priv->dev, "Unable to acquire IRQ %d\n", priv->irq); + return ret; + } + + return 0; +} + +static void th1520_mbox_shutdown(struct mbox_chan *chan) +{ + struct th1520_mbox_priv *priv = to_th1520_mbox_priv(chan->mbox); + struct th1520_mbox_con_priv *cp = chan->con_priv; + int mask_bit; + + free_irq(priv->irq, chan); + + /* clear the chan mask */ + mask_bit = th1520_mbox_chan_id_to_mapbit(cp); + th1520_mbox_rmw(priv, TH_1520_MBOX_MASK, 0, BIT(mask_bit)); +} + +static const struct mbox_chan_ops th1520_mbox_ops = { + .send_data = th1520_mbox_send_data, + .startup = th1520_mbox_startup, + .shutdown = th1520_mbox_shutdown, +}; + +static int th1520_mbox_init_generic(struct th1520_mbox_priv *priv) +{ +#ifdef CONFIG_PM_SLEEP + priv->ctx = devm_kzalloc(priv->dev, sizeof(*priv->ctx), GFP_KERNEL); + if (!priv->ctx) + return -ENOMEM; +#endif + /* Set default configuration */ + th1520_mbox_write(priv, 0xff, TH_1520_MBOX_CLR); + th1520_mbox_write(priv, 0x0, TH_1520_MBOX_MASK); + return 0; +} + +static struct mbox_chan *th1520_mbox_xlate(struct mbox_controller *mbox, + const struct of_phandle_args *sp) +{ + u32 chan; + + if (sp->args_count != 1) { + dev_err(mbox->dev, "Invalid argument count %d\n", + sp->args_count); + return ERR_PTR(-EINVAL); + } + + chan = sp->args[0]; /* comm remote channel */ + + if (chan >= mbox->num_chans) { + dev_err(mbox->dev, "Not supported channel number: %d\n", chan); + return ERR_PTR(-EINVAL); + } + + if (chan == TH_1520_MBOX_ICU_KERNEL_CPU0) { + dev_err(mbox->dev, "Cannot communicate with yourself\n"); + return ERR_PTR(-EINVAL); + } + + return &mbox->chans[chan]; +} + +static void __iomem *th1520_map_mmio(struct platform_device *pdev, + char *res_name, size_t offset) +{ + void __iomem *mapped; + struct resource *res; + + res = platform_get_resource_byname(pdev, IORESOURCE_MEM, res_name); + + if (!res) { + dev_err(&pdev->dev, "Failed to get resource: %s\n", res_name); + return ERR_PTR(-EINVAL); + } + + mapped = devm_ioremap(&pdev->dev, res->start + offset, + resource_size(res) - offset); + if (IS_ERR(mapped)) + dev_err(&pdev->dev, "Failed to map resource: %s\n", res_name); + + return mapped; +} + +static void th1520_disable_clk(void *data) +{ + struct th1520_mbox_priv *priv = data; + + clk_bulk_disable_unprepare(ARRAY_SIZE(priv->clocks), priv->clocks); +} + +static int th1520_mbox_probe(struct platform_device *pdev) +{ + struct device *dev = &pdev->dev; + struct th1520_mbox_priv *priv; + unsigned int remote_idx = 0; + unsigned int i; + int ret; + + priv = devm_kzalloc(dev, sizeof(*priv), GFP_KERNEL); + if (!priv) + return -ENOMEM; + + priv->dev = dev; + + priv->clocks[0].id = "clk-local"; + priv->clocks[1].id = "clk-remote-icu0"; + priv->clocks[2].id = "clk-remote-icu1"; + priv->clocks[3].id = "clk-remote-icu2"; + + ret = devm_clk_bulk_get(dev, ARRAY_SIZE(priv->clocks), + priv->clocks); + if (ret) { + dev_err(dev, "Failed to get clocks\n"); + return ret; + } + + ret = clk_bulk_prepare_enable(ARRAY_SIZE(priv->clocks), priv->clocks); + if (ret) { + dev_err(dev, "Failed to enable clocks\n"); + return ret; + } + + ret = devm_add_action_or_reset(dev, th1520_disable_clk, priv); + if (ret) { + clk_bulk_disable_unprepare(ARRAY_SIZE(priv->clocks), priv->clocks); + return ret; + } + + /* + * The address mappings in the device tree align precisely with those + * outlined in the manual. However, register offsets within these + * mapped regions are irregular, particularly for remote-icu0. + * Consequently, th1520_map_mmio() requires an additional parameter to + * handle this quirk. + */ + priv->local_icu[TH_1520_MBOX_ICU_KERNEL_CPU0] = + th1520_map_mmio(pdev, "local", 0x0); + if (IS_ERR(priv->local_icu[TH_1520_MBOX_ICU_KERNEL_CPU0])) + return PTR_ERR(priv->local_icu[TH_1520_MBOX_ICU_KERNEL_CPU0]); + + priv->remote_icu[0] = th1520_map_mmio(pdev, "remote-icu0", 0x4000); + if (IS_ERR(priv->remote_icu[0])) + return PTR_ERR(priv->remote_icu[0]); + + priv->remote_icu[1] = th1520_map_mmio(pdev, "remote-icu1", 0x0); + if (IS_ERR(priv->remote_icu[1])) + return PTR_ERR(priv->remote_icu[1]); + + priv->remote_icu[2] = th1520_map_mmio(pdev, "remote-icu2", 0x0); + if (IS_ERR(priv->remote_icu[2])) + return PTR_ERR(priv->remote_icu[2]); + + priv->local_icu[TH_1520_MBOX_ICU_CPU1] = + priv->local_icu[TH_1520_MBOX_ICU_KERNEL_CPU0] + + TH_1520_MBOX_CHAN_RES_SIZE; + priv->local_icu[TH_1520_MBOX_ICU_CPU2] = + priv->local_icu[TH_1520_MBOX_ICU_CPU1] + + TH_1520_MBOX_CHAN_RES_SIZE; + priv->local_icu[TH_1520_MBOX_ICU_CPU3] = + priv->local_icu[TH_1520_MBOX_ICU_CPU2] + + TH_1520_MBOX_CHAN_RES_SIZE; + + priv->cur_cpu_ch_base = priv->local_icu[TH_1520_MBOX_ICU_KERNEL_CPU0]; + + priv->irq = platform_get_irq(pdev, 0); + if (priv->irq < 0) + return priv->irq; + + /* init the chans */ + for (i = 0; i < TH_1520_MBOX_CHANS; i++) { + struct th1520_mbox_con_priv *cp = &priv->con_priv[i]; + + cp->idx = i; + cp->chan = &priv->mbox_chans[i]; + priv->mbox_chans[i].con_priv = cp; + snprintf(cp->irq_desc, sizeof(cp->irq_desc), + "th1520_mbox_chan[%i]", cp->idx); + + cp->comm_local_base = priv->local_icu[i]; + if (i != TH_1520_MBOX_ICU_KERNEL_CPU0) { + cp->comm_remote_base = priv->remote_icu[remote_idx]; + remote_idx++; + } + } + + spin_lock_init(&priv->mbox_lock); + + priv->mbox.dev = dev; + priv->mbox.ops = &th1520_mbox_ops; + priv->mbox.chans = priv->mbox_chans; + priv->mbox.num_chans = TH_1520_MBOX_CHANS; + priv->mbox.of_xlate = th1520_mbox_xlate; + priv->mbox.txdone_irq = true; + + platform_set_drvdata(pdev, priv); + + ret = th1520_mbox_init_generic(priv); + if (ret) { + dev_err(dev, "Failed to init mailbox context\n"); + return ret; + } + + return devm_mbox_controller_register(dev, &priv->mbox); +} + +static const struct of_device_id th1520_mbox_dt_ids[] = { + { .compatible = "thead,th1520-mbox" }, + {} +}; +MODULE_DEVICE_TABLE(of, th1520_mbox_dt_ids); + +#ifdef CONFIG_PM_SLEEP +static int __maybe_unused th1520_mbox_suspend_noirq(struct device *dev) +{ + struct th1520_mbox_priv *priv = dev_get_drvdata(dev); + struct th1520_mbox_context *ctx = priv->ctx; + u32 i; + /* + * ONLY interrupt mask bit should be stored and restores. + * INFO data all assumed to be lost. + */ + for (i = 0; i < TH_1520_MBOX_CHANS; i++) { + ctx->intr_mask[i] = + ioread32(priv->local_icu[i] + TH_1520_MBOX_MASK); + } + return 0; +} + +static int __maybe_unused th1520_mbox_resume_noirq(struct device *dev) +{ + struct th1520_mbox_priv *priv = dev_get_drvdata(dev); + struct th1520_mbox_context *ctx = priv->ctx; + u32 i; + + for (i = 0; i < TH_1520_MBOX_CHANS; i++) { + iowrite32(ctx->intr_mask[i], + priv->local_icu[i] + TH_1520_MBOX_MASK); + } + + return 0; +} +#endif + +static int __maybe_unused th1520_mbox_runtime_suspend(struct device *dev) +{ + struct th1520_mbox_priv *priv = dev_get_drvdata(dev); + + clk_bulk_disable_unprepare(ARRAY_SIZE(priv->clocks), priv->clocks); + + return 0; +} + +static int __maybe_unused th1520_mbox_runtime_resume(struct device *dev) +{ + struct th1520_mbox_priv *priv = dev_get_drvdata(dev); + int ret; + + ret = clk_bulk_prepare_enable(ARRAY_SIZE(priv->clocks), priv->clocks); + if (ret) + dev_err(dev, "Failed to enable clocks in runtime resume\n"); + + return ret; +} + +static const struct dev_pm_ops th1520_mbox_pm_ops = { +#ifdef CONFIG_PM_SLEEP + SET_NOIRQ_SYSTEM_SLEEP_PM_OPS(th1520_mbox_suspend_noirq, + th1520_mbox_resume_noirq) +#endif + SET_RUNTIME_PM_OPS(th1520_mbox_runtime_suspend, + th1520_mbox_runtime_resume, NULL) +}; + +static struct platform_driver th1520_mbox_driver = { + .probe = th1520_mbox_probe, + .driver = { + .name = "th1520-mbox", + .of_match_table = th1520_mbox_dt_ids, + .pm = &th1520_mbox_pm_ops, + }, +}; +module_platform_driver(th1520_mbox_driver); + +MODULE_DESCRIPTION("Thead TH-1520 mailbox IPC driver"); +MODULE_LICENSE("GPL"); |