diff options
Diffstat (limited to 'drivers/mailbox/mailbox-xgene-slimpro.c')
| -rw-r--r-- | drivers/mailbox/mailbox-xgene-slimpro.c | 262 |
1 files changed, 262 insertions, 0 deletions
diff --git a/drivers/mailbox/mailbox-xgene-slimpro.c b/drivers/mailbox/mailbox-xgene-slimpro.c new file mode 100644 index 000000000..de260799f --- /dev/null +++ b/drivers/mailbox/mailbox-xgene-slimpro.c @@ -0,0 +1,262 @@ +// SPDX-License-Identifier: GPL-2.0-or-later +/* + * APM X-Gene SLIMpro MailBox Driver + * + * Copyright (c) 2015, Applied Micro Circuits Corporation + * Author: Feng Kan fkan@apm.com + */ +#include <linux/acpi.h> +#include <linux/delay.h> +#include <linux/interrupt.h> +#include <linux/io.h> +#include <linux/mailbox_controller.h> +#include <linux/module.h> +#include <linux/of.h> +#include <linux/platform_device.h> +#include <linux/spinlock.h> + +#define MBOX_CON_NAME "slimpro-mbox" +#define MBOX_REG_SET_OFFSET 0x1000 +#define MBOX_CNT 8 +#define MBOX_STATUS_AVAIL_MASK BIT(16) +#define MBOX_STATUS_ACK_MASK BIT(0) + +/* Configuration and Status Registers */ +#define REG_DB_IN 0x00 +#define REG_DB_DIN0 0x04 +#define REG_DB_DIN1 0x08 +#define REG_DB_OUT 0x10 +#define REG_DB_DOUT0 0x14 +#define REG_DB_DOUT1 0x18 +#define REG_DB_STAT 0x20 +#define REG_DB_STATMASK 0x24 + +/** + * X-Gene SlimPRO mailbox channel information + * + * @dev: Device to which it is attached + * @chan: Pointer to mailbox communication channel + * @reg: Base address to access channel registers + * @irq: Interrupt number of the channel + * @rx_msg: Received message storage + */ +struct slimpro_mbox_chan { + struct device *dev; + struct mbox_chan *chan; + void __iomem *reg; + int irq; + u32 rx_msg[3]; +}; + +/** + * X-Gene SlimPRO Mailbox controller data + * + * X-Gene SlimPRO Mailbox controller has 8 commnunication channels. + * Each channel has a separate IRQ number assgined to it. + * + * @mb_ctrl: Representation of the commnunication channel controller + * @mc: Array of SlimPRO mailbox channels of the controller + * @chans: Array of mailbox communication channels + * + */ +struct slimpro_mbox { + struct mbox_controller mb_ctrl; + struct slimpro_mbox_chan mc[MBOX_CNT]; + struct mbox_chan chans[MBOX_CNT]; +}; + +static void mb_chan_send_msg(struct slimpro_mbox_chan *mb_chan, u32 *msg) +{ + writel(msg[1], mb_chan->reg + REG_DB_DOUT0); + writel(msg[2], mb_chan->reg + REG_DB_DOUT1); + writel(msg[0], mb_chan->reg + REG_DB_OUT); +} + +static void mb_chan_recv_msg(struct slimpro_mbox_chan *mb_chan) +{ + mb_chan->rx_msg[1] = readl(mb_chan->reg + REG_DB_DIN0); + mb_chan->rx_msg[2] = readl(mb_chan->reg + REG_DB_DIN1); + mb_chan->rx_msg[0] = readl(mb_chan->reg + REG_DB_IN); +} + +static int mb_chan_status_ack(struct slimpro_mbox_chan *mb_chan) +{ + u32 val = readl(mb_chan->reg + REG_DB_STAT); + + if (val & MBOX_STATUS_ACK_MASK) { + writel(MBOX_STATUS_ACK_MASK, mb_chan->reg + REG_DB_STAT); + return 1; + } + return 0; +} + +static int mb_chan_status_avail(struct slimpro_mbox_chan *mb_chan) +{ + u32 val = readl(mb_chan->reg + REG_DB_STAT); + + if (val & MBOX_STATUS_AVAIL_MASK) { + mb_chan_recv_msg(mb_chan); + writel(MBOX_STATUS_AVAIL_MASK, mb_chan->reg + REG_DB_STAT); + return 1; + } + return 0; +} + +static irqreturn_t slimpro_mbox_irq(int irq, void *id) +{ + struct slimpro_mbox_chan *mb_chan = id; + + if (mb_chan_status_ack(mb_chan)) + mbox_chan_txdone(mb_chan->chan, 0); + + if (mb_chan_status_avail(mb_chan)) + mbox_chan_received_data(mb_chan->chan, mb_chan->rx_msg); + + return IRQ_HANDLED; +} + +static int slimpro_mbox_send_data(struct mbox_chan *chan, void *msg) +{ + struct slimpro_mbox_chan *mb_chan = chan->con_priv; + + mb_chan_send_msg(mb_chan, msg); + return 0; +} + +static int slimpro_mbox_startup(struct mbox_chan *chan) +{ + struct slimpro_mbox_chan *mb_chan = chan->con_priv; + int rc; + u32 val; + + rc = devm_request_irq(mb_chan->dev, mb_chan->irq, slimpro_mbox_irq, 0, + MBOX_CON_NAME, mb_chan); + if (unlikely(rc)) { + dev_err(mb_chan->dev, "failed to register mailbox interrupt %d\n", + mb_chan->irq); + return rc; + } + + /* Enable HW interrupt */ + writel(MBOX_STATUS_ACK_MASK | MBOX_STATUS_AVAIL_MASK, + mb_chan->reg + REG_DB_STAT); + /* Unmask doorbell status interrupt */ + val = readl(mb_chan->reg + REG_DB_STATMASK); + val &= ~(MBOX_STATUS_ACK_MASK | MBOX_STATUS_AVAIL_MASK); + writel(val, mb_chan->reg + REG_DB_STATMASK); + + return 0; +} + +static void slimpro_mbox_shutdown(struct mbox_chan *chan) +{ + struct slimpro_mbox_chan *mb_chan = chan->con_priv; + u32 val; + + /* Mask doorbell status interrupt */ + val = readl(mb_chan->reg + REG_DB_STATMASK); + val |= (MBOX_STATUS_ACK_MASK | MBOX_STATUS_AVAIL_MASK); + writel(val, mb_chan->reg + REG_DB_STATMASK); + + devm_free_irq(mb_chan->dev, mb_chan->irq, mb_chan); +} + +static const struct mbox_chan_ops slimpro_mbox_ops = { + .send_data = slimpro_mbox_send_data, + .startup = slimpro_mbox_startup, + .shutdown = slimpro_mbox_shutdown, +}; + +static int slimpro_mbox_probe(struct platform_device *pdev) +{ + struct slimpro_mbox *ctx; + struct resource *regs; + void __iomem *mb_base; + int rc; + int i; + + ctx = devm_kzalloc(&pdev->dev, sizeof(struct slimpro_mbox), GFP_KERNEL); + if (!ctx) + return -ENOMEM; + + platform_set_drvdata(pdev, ctx); + + regs = platform_get_resource(pdev, IORESOURCE_MEM, 0); + mb_base = devm_ioremap_resource(&pdev->dev, regs); + if (IS_ERR(mb_base)) + return PTR_ERR(mb_base); + + /* Setup mailbox links */ + for (i = 0; i < MBOX_CNT; i++) { + ctx->mc[i].irq = platform_get_irq(pdev, i); + if (ctx->mc[i].irq < 0) { + if (i == 0) { + dev_err(&pdev->dev, "no available IRQ\n"); + return -EINVAL; + } + dev_info(&pdev->dev, "no IRQ for channel %d\n", i); + break; + } + + ctx->mc[i].dev = &pdev->dev; + ctx->mc[i].reg = mb_base + i * MBOX_REG_SET_OFFSET; + ctx->mc[i].chan = &ctx->chans[i]; + ctx->chans[i].con_priv = &ctx->mc[i]; + } + + /* Setup mailbox controller */ + ctx->mb_ctrl.dev = &pdev->dev; + ctx->mb_ctrl.chans = ctx->chans; + ctx->mb_ctrl.txdone_irq = true; + ctx->mb_ctrl.ops = &slimpro_mbox_ops; + ctx->mb_ctrl.num_chans = i; + + rc = devm_mbox_controller_register(&pdev->dev, &ctx->mb_ctrl); + if (rc) { + dev_err(&pdev->dev, + "APM X-Gene SLIMpro MailBox register failed:%d\n", rc); + return rc; + } + + dev_info(&pdev->dev, "APM X-Gene SLIMpro MailBox registered\n"); + return 0; +} + +static const struct of_device_id slimpro_of_match[] = { + {.compatible = "apm,xgene-slimpro-mbox" }, + { }, +}; +MODULE_DEVICE_TABLE(of, slimpro_of_match); + +#ifdef CONFIG_ACPI +static const struct acpi_device_id slimpro_acpi_ids[] = { + {"APMC0D01", 0}, + {} +}; +MODULE_DEVICE_TABLE(acpi, slimpro_acpi_ids); +#endif + +static struct platform_driver slimpro_mbox_driver = { + .probe = slimpro_mbox_probe, + .driver = { + .name = "xgene-slimpro-mbox", + .of_match_table = of_match_ptr(slimpro_of_match), + .acpi_match_table = ACPI_PTR(slimpro_acpi_ids) + }, +}; + +static int __init slimpro_mbox_init(void) +{ + return platform_driver_register(&slimpro_mbox_driver); +} + +static void __exit slimpro_mbox_exit(void) +{ + platform_driver_unregister(&slimpro_mbox_driver); +} + +subsys_initcall(slimpro_mbox_init); +module_exit(slimpro_mbox_exit); + +MODULE_DESCRIPTION("APM X-Gene SLIMpro Mailbox Driver"); +MODULE_LICENSE("GPL"); |