On 26.06.2018 12:09, A.s. Dong wrote: >> -----Original Message----- >> From: Oleksij Rempel [mailto:o.rempel@xxxxxxxxxxxxxx] >> Sent: Friday, June 15, 2018 5:51 PM >> To: Shawn Guo <shawnguo@xxxxxxxxxx>; Fabio Estevam >> <fabio.estevam@xxxxxxx>; Rob Herring <robh+dt@xxxxxxxxxx>; Mark >> Rutland <mark.rutland@xxxxxxx>; A.s. Dong <aisheng.dong@xxxxxxx> >> Cc: Oleksij Rempel <o.rempel@xxxxxxxxxxxxxx>; kernel@xxxxxxxxxxxxxx; >> linux-arm-kernel@xxxxxxxxxxxxxxxxxxx; devicetree@xxxxxxxxxxxxxxx; linux- >> clk@xxxxxxxxxxxxxxx; dl-linux-imx <linux-imx@xxxxxxx> >> Subject: [PATCH v2 4/4] mailbox: Add support for i.MX7D messaging unit >> >> The Mailbox controller is able to send messages (up to 4 32 bit words) >> between the endpoints. >> >> This driver was tested using the mailbox-test driver sending messages >> between the Cortex-A7 and the Cortex-M4. >> >> Signed-off-by: Oleksij Rempel <o.rempel@xxxxxxxxxxxxxx> >> --- >> drivers/mailbox/Kconfig | 6 + >> drivers/mailbox/Makefile | 2 + >> drivers/mailbox/imx-mailbox.c | 288 >> ++++++++++++++++++++++++++++++++++ >> 3 files changed, 296 insertions(+) >> create mode 100644 drivers/mailbox/imx-mailbox.c >> >> diff --git a/drivers/mailbox/Kconfig b/drivers/mailbox/Kconfig index >> a2bb27446dce..e1d2738a2e4c 100644 >> --- a/drivers/mailbox/Kconfig >> +++ b/drivers/mailbox/Kconfig >> @@ -15,6 +15,12 @@ config ARM_MHU >> The controller has 3 mailbox channels, the last of which can be >> used in Secure mode only. >> >> +config IMX_MBOX >> + tristate "iMX Mailbox" >> + depends on SOC_IMX7D || COMPILE_TEST >> + help >> + Mailbox implementation for iMX7D Messaging Unit (MU). >> + >> config PLATFORM_MHU >> tristate "Platform MHU Mailbox" >> depends on OF >> diff --git a/drivers/mailbox/Makefile b/drivers/mailbox/Makefile index >> cc23c3a43fcd..ba2fe1b6dd62 100644 >> --- a/drivers/mailbox/Makefile >> +++ b/drivers/mailbox/Makefile >> @@ -7,6 +7,8 @@ obj-$(CONFIG_MAILBOX_TEST) += mailbox-test.o >> >> obj-$(CONFIG_ARM_MHU) += arm_mhu.o >> >> +obj-$(CONFIG_IMX_MBOX) += imx-mailbox.o >> + >> obj-$(CONFIG_PLATFORM_MHU) += platform_mhu.o >> >> obj-$(CONFIG_PL320_MBOX) += pl320-ipc.o >> diff --git a/drivers/mailbox/imx-mailbox.c b/drivers/mailbox/imx-mailbox.c >> new file mode 100644 index 000000000000..e3f621cb1d30 >> --- /dev/null >> +++ b/drivers/mailbox/imx-mailbox.c >> @@ -0,0 +1,288 @@ >> +// SPDX-License-Identifier: GPL-2.0 >> +/* >> + * Copyright (c) 2018 Pengutronix, Oleksij Rempel >> +<o.rempel@xxxxxxxxxxxxxx> */ >> + >> +#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> >> + >> +/* Transmit Register */ >> +#define IMX_MU_xTRn(x) (0x00 + 4 * (x)) >> +/* Receive Register */ >> +#define IMX_MU_xRRn(x) (0x10 + 4 * (x)) >> +/* Status Register */ >> +#define IMX_MU_xSR 0x20 >> +#define IMX_MU_xSR_TEn(x) BIT(20 + (x)) >> +#define IMX_MU_xSR_RFn(x) BIT(24 + (x)) >> +#define IMX_MU_xSR_BRDIP BIT(9) >> + >> +/* Control Register */ >> +#define IMX_MU_xCR 0x24 >> +/* Transmit Interrupt Enable */ >> +#define IMX_MU_xCR_TIEn(x) BIT(20 + (x)) >> +/* Receive Interrupt Enable */ >> +#define IMX_MU_xCR_RIEn(x) BIT(24 + (x)) >> + >> +#define IMX_MU_MAX_CHANS 4u >> + >> +struct imx_mu_priv; >> + >> +struct imx_mu_cfg { >> + unsigned int chans; >> + void (*init_hw)(struct imx_mu_priv *priv); }; >> + >> +struct imx_mu_con_priv { >> + int irq; >> + unsigned int bidx; >> + unsigned int idx; >> +}; >> + >> +struct imx_mu_priv { >> + struct device *dev; >> + const struct imx_mu_cfg *dcfg; >> + void __iomem *base; >> + >> + struct mbox_controller mbox; >> + struct mbox_chan mbox_chans[IMX_MU_MAX_CHANS]; >> + >> + struct imx_mu_con_priv con_priv[IMX_MU_MAX_CHANS]; >> + struct clk *clk; >> +}; >> + >> +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_rmw(struct imx_mu_priv *priv, u32 offs, u32 set, u32 >> +clr) { >> + u32 val; >> + >> + val = imx_mu_read(priv, offs); >> + val &= ~clr; >> + val |= set; >> + imx_mu_write(priv, val, offs); >> + >> + return val; >> +} >> + >> +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, dat; >> + >> + val = imx_mu_read(priv, IMX_MU_xSR); >> + val &= IMX_MU_xSR_TEn(cp->bidx) | IMX_MU_xSR_RFn(cp->bidx); >> + if (!val) >> + return IRQ_NONE; >> + >> + if (val & IMX_MU_xSR_TEn(cp->bidx)) { > > I'm wondering whether this can work properly for multi consumers > at the same time. > Because xSR_TEn is 1 by default and four virtual channels actually > are using the same interrupt. That means channel 1 interrupt may > cause channel 2 believe it's txdone. > Have we tested such using? see imx_mu_send_data() ..... imx_mu_rmw(priv, IMX_MU_xCR, IMX_MU_xSR_TEn(cp->bidx), 0); > >> + imx_mu_rmw(priv, IMX_MU_xCR, 0, IMX_MU_xCR_TIEn(cp- >>> bidx)); and here ^^^ TX status is enabled only for send and disabled as soon at transfer is done. >> + mbox_chan_txdone(chan, 0); >> + } >> + >> + if (val & IMX_MU_xSR_RFn(cp->bidx)) { >> + dat = imx_mu_read(priv, IMX_MU_xRRn(cp->idx)); >> + mbox_chan_received_data(chan, (void *)&dat); >> + } >> + >> + return IRQ_HANDLED; >> +} >> + >> +static bool imx_mu_last_tx_done(struct mbox_chan *chan) { >> + struct imx_mu_priv *priv = to_imx_mu_priv(chan->mbox); >> + struct imx_mu_con_priv *cp = chan->con_priv; >> + u32 val; >> + >> + val = imx_mu_read(priv, IMX_MU_xSR); >> + /* test if transmit register is empty */ >> + return (!!(val & IMX_MU_xSR_TEn(cp->bidx))); } >> + >> +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; >> + u32 *arg = data; >> + >> + if (!imx_mu_last_tx_done(chan)) >> + return -EBUSY; >> + >> + imx_mu_write(priv, *arg, IMX_MU_xTRn(cp->idx)); >> + imx_mu_rmw(priv, IMX_MU_xCR, IMX_MU_xSR_TEn(cp->bidx), 0); >> + >> + return 0; >> +} > > Since Sascha is requesting to write a generic MU mailbox driver for both > SCU MU and M4 case, the current way using virtual channels in this patch > only send one word a time obviously can't fit for SCU MU clients well. > Do you think if we can refer to TI case to design a generic data transfer > protocol to allow send multi words which is more close to SCU? According to your code, you are able to send 1 word message. It means, your SCU is configured to trigger an interrupt or status update if REG0 was written. The same is true for 2, 3, 4 and 5 word messages. If the MU configuration would look like you it described, you would be forced to write always 4 words, even for 1 word message. > include/linux/soc/ti/ti-msgmgr.h > struct ti_msgmgr_message { > size_t len; > u8 *buf; > }; > > Or we try to support both type transfer protocols in this driver? Sure. ti-msgmgr.c is a good example. You will probably need reduced variant of it. It is generic enough to make it useful not only for SCU. > That may introduce much complexities, personally I'm not quite > like that. I expect 50-150 lines of extra code. > Regards > Dong Aisheng > >> + >> +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; >> + int ret; >> + >> + ret = request_irq(cp->irq, imx_mu_isr, >> + IRQF_SHARED, "imx_mu_chan", chan); >> + if (ret) { >> + dev_err(chan->mbox->dev, >> + "Unable to acquire IRQ %d\n", cp->irq); >> + return ret; >> + } >> + >> + imx_mu_rmw(priv, IMX_MU_xCR, IMX_MU_xCR_RIEn(cp->bidx), 0); >> + >> + 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; >> + >> + imx_mu_rmw(priv, IMX_MU_xCR, 0, >> + IMX_MU_xCR_TIEn(cp->bidx) | IMX_MU_xCR_RIEn(cp- >>> bidx)); >> + >> + free_irq(cp->irq, chan); >> +} >> + >> +static const struct mbox_chan_ops imx_mu_ops = { >> + .send_data = imx_mu_send_data, >> + .startup = imx_mu_startup, >> + .shutdown = imx_mu_shutdown, >> +}; >> + >> +static int imx_mu_probe(struct platform_device *pdev) { >> + struct device *dev = &pdev->dev; >> + struct resource *iomem; >> + struct imx_mu_priv *priv; >> + const struct imx_mu_cfg *dcfg; >> + unsigned int i, chans; >> + int irq, ret; >> + >> + priv = devm_kzalloc(dev, sizeof(*priv), GFP_KERNEL); >> + if (!priv) >> + return -ENOMEM; >> + >> + dcfg = of_device_get_match_data(dev); >> + if (!dcfg) >> + return -EINVAL; >> + >> + priv->dcfg = dcfg; >> + priv->dev = dev; >> + >> + iomem = platform_get_resource(pdev, IORESOURCE_MEM, 0); >> + priv->base = devm_ioremap_resource(&pdev->dev, iomem); >> + if (IS_ERR(priv->base)) >> + return PTR_ERR(priv->base); >> + >> + irq = platform_get_irq(pdev, 0); >> + if (irq <= 0) >> + return irq < 0 ? irq : -EINVAL; >> + >> + priv->clk = devm_clk_get(dev, NULL); >> + if (IS_ERR(priv->clk)) { >> + if (PTR_ERR(priv->clk) == -ENOENT) { >> + priv->clk = NULL; >> + } else { >> + dev_err(dev, "Failed to get clock\n"); >> + return PTR_ERR(priv->clk); >> + } >> + } >> + >> + ret = clk_prepare_enable(priv->clk); >> + if (ret) { >> + dev_err(dev, "Failed to enable clock\n"); >> + return ret; >> + } >> + >> + chans = min(dcfg->chans, IMX_MU_MAX_CHANS); >> + /* Initialize channel identifiers */ >> + for (i = 0; i < chans; i++) { >> + struct imx_mu_con_priv *cp = &priv->con_priv[i]; >> + >> + cp->bidx = 3 - i; >> + cp->idx = i; >> + cp->irq = irq; >> + priv->mbox_chans[i].con_priv = cp; >> + } >> + >> + priv->mbox.dev = dev; >> + priv->mbox.ops = &imx_mu_ops; >> + priv->mbox.chans = priv->mbox_chans; >> + priv->mbox.num_chans = chans; >> + priv->mbox.txdone_irq = true; >> + >> + platform_set_drvdata(pdev, priv); >> + >> + if (priv->dcfg->init_hw) >> + priv->dcfg->init_hw(priv); >> + >> + return mbox_controller_register(&priv->mbox); >> +} >> + >> +static int imx_mu_remove(struct platform_device *pdev) { >> + struct imx_mu_priv *priv = platform_get_drvdata(pdev); >> + >> + mbox_controller_unregister(&priv->mbox); >> + clk_disable_unprepare(priv->clk); >> + >> + return 0; >> +} >> + >> + >> +static void imx_mu_init_imx7d_a(struct imx_mu_priv *priv) { >> + /* Set default config */ >> + imx_mu_write(priv, 0, IMX_MU_xCR); >> +} >> + >> +static const struct imx_mu_cfg imx_mu_cfg_imx7d_a = { >> + .chans = IMX_MU_MAX_CHANS, >> + .init_hw = imx_mu_init_imx7d_a, >> +}; >> + >> +static const struct imx_mu_cfg imx_mu_cfg_imx7d_b = { >> + .chans = IMX_MU_MAX_CHANS, >> +}; >> + >> +static const struct of_device_id imx_mu_dt_ids[] = { >> + { .compatible = "fsl,imx7s-mu-a", .data = &imx_mu_cfg_imx7d_a }, >> + { .compatible = "fsl,imx7s-mu-b", .data = &imx_mu_cfg_imx7d_b }, >> + { }, >> +}; >> +MODULE_DEVICE_TABLE(of, imx_mu_dt_ids); >> + >> +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, >> + }, >> +}; >> +module_platform_driver(imx_mu_driver); >> + >> +MODULE_AUTHOR("Oleksij Rempel <o.rempel@xxxxxxxxxxxxxx>"); >> +MODULE_DESCRIPTION("Message Unit driver for i.MX"); >> MODULE_LICENSE("GPL >> +v2"); >> -- >> 2.17.1 > > >
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