On 9 February 2016 at 20:46, Duc Dang <dhdang@xxxxxxx> wrote: > On Tue, Feb 9, 2016 at 8:40 AM, Mathieu Poirier > <mathieu.poirier@xxxxxxxxxx> wrote: >> On 8 February 2016 at 15:04, Duc Dang <dhdang@xxxxxxx> wrote: >>> X-Gene mailbox controller provides 8 mailbox channels, with >>> each channel has a dedicated interrupt line. >>> >>> Signed-off-by: Feng Kan <fkan@xxxxxxx> >>> Signed-off-by: Duc Dang <dhdang@xxxxxxx> >>> --- >>> Changes since v4: >>> - Rebase over v4.5-rc1 >>> - Fix section mistmatch warning by removing >>> __init in slimpro_mbox_probe declaration >>> - Correctly print channel number when >>> there is no IRQ for that channel >>> >>> Changes since v3: >>> - Rebase over v4.4 >>> - Remove 'id' in slimpro_mbox_chan structure >>> - Remove small functions that are only called once >>> and fold them into the other callers >>> - Remove void* pointer type cast >>> - Relax the number of mailbox IRQs condition >>> - Use subsys_initcall to guarantee mailbox driver >>> will be registered before any other dependent driver >>> is loaded. >>> >>> drivers/mailbox/Kconfig | 9 ++ >>> drivers/mailbox/Makefile | 2 + >>> drivers/mailbox/mailbox-xgene-slimpro.c | 264 ++++++++++++++++++++++++++++++++ >>> 3 files changed, 275 insertions(+) >>> create mode 100644 drivers/mailbox/mailbox-xgene-slimpro.c >>> >>> diff --git a/drivers/mailbox/Kconfig b/drivers/mailbox/Kconfig >>> index 546d05f..678e434 100644 >>> --- a/drivers/mailbox/Kconfig >>> +++ b/drivers/mailbox/Kconfig >>> @@ -85,4 +85,13 @@ config MAILBOX_TEST >>> Test client to help with testing new Controller driver >>> implementations. >>> >>> +config XGENE_SLIMPRO_MBOX >>> + tristate "APM SoC X-Gene SLIMpro Mailbox Controller" >>> + depends on ARCH_XGENE >>> + help >>> + An implementation of the APM X-Gene Interprocessor Communication >>> + Mailbox (IPCM) between the ARM 64-bit cores and SLIMpro controller. >>> + It is used to send short messages between ARM64-bit cores and >>> + the SLIMpro Management Engine, primarily for PM. Say Y here if you >>> + want to use the APM X-Gene SLIMpro IPCM support. >>> endif >>> diff --git a/drivers/mailbox/Makefile b/drivers/mailbox/Makefile >>> index 92435ef..b602ef8 100644 >>> --- a/drivers/mailbox/Makefile >>> +++ b/drivers/mailbox/Makefile >>> @@ -17,3 +17,5 @@ obj-$(CONFIG_ALTERA_MBOX) += mailbox-altera.o >>> obj-$(CONFIG_BCM2835_MBOX) += bcm2835-mailbox.o >>> >>> obj-$(CONFIG_STI_MBOX) += mailbox-sti.o >>> + >>> +obj-$(CONFIG_XGENE_SLIMPRO_MBOX) += mailbox-xgene-slimpro.o >>> diff --git a/drivers/mailbox/mailbox-xgene-slimpro.c b/drivers/mailbox/mailbox-xgene-slimpro.c >>> new file mode 100644 >>> index 0000000..0ea1eb8 >>> --- /dev/null >>> +++ b/drivers/mailbox/mailbox-xgene-slimpro.c >>> @@ -0,0 +1,264 @@ >>> +/* >>> + * APM X-Gene SLIMpro MailBox Driver >>> + * >>> + * Copyright (c) 2015, Applied Micro Circuits Corporation >>> + * Author: Feng Kan fkan@xxxxxxx >>> + * >>> + * This program is free software; you can redistribute it and/or >>> + * modify it under the terms of the GNU General Public License as >>> + * published by the Free Software Foundation; either version 2 of >>> + * the License, or (at your option) any later version. >>> + * >>> + * This program is distributed in the hope that 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. >>> + * >>> + * You should have received a copy of the GNU General Public License >>> + * along with this program; if not, see <http://www.gnu.org/licenses/>. >>> + * >>> + */ >>> +#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 >>> + >>> +struct slimpro_mbox_chan { >>> + struct device *dev; >>> + struct mbox_chan *chan; >>> + void __iomem *reg; >>> + int irq; >>> + u32 rx_msg[3]; >>> +}; >>> + >>> +struct slimpro_mbox { >>> + struct mbox_controller mb_ctrl; >>> + struct slimpro_mbox_chan mc[MBOX_CNT]; >>> + struct mbox_chan chans[MBOX_CNT]; >>> +}; >> >> The above two structure declaration could use kernel style documentation. > > Can you please clarify or give an example? I looked into several files > in drivers/mailbox/ and drivers/irqchip but could not find what I need > to tweak. http://lxr.free-electrons.com/source/drivers/mailbox/mailbox-sti.c#L42 > >> >>> + >>> +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); >>> +} >> >> Is there a requirement that operations in the above two functions be >> ordered? If not significant gains could be achieved by using >> writel/readl_relaxed(). Same comment for the rest of this driver. > > The 'writes' need to be in order as writing to REG_DB_OUT will trigger > interrupt, so I want the other 2 'writes' complete before it. > > After the receiver get the message, it will clear door bell available > interrupt request, this will also trigger a door bell acknowledge > interrupt. So the 'read' to get the message and the 'write' to clear > the door bell available interrupt must be in order as well. > > Regards, > Duc Dang. >> >> Thanks, >> Mathieu >> >>> + >>> +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 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 (IS_ERR(ctx)) >>> + return PTR_ERR(ctx); >>> + >>> + platform_set_drvdata(pdev, ctx); >>> + >>> + regs = platform_get_resource(pdev, IORESOURCE_MEM, 0); >>> + mb_base = devm_ioremap(&pdev->dev, regs->start, resource_size(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 = mbox_controller_register(&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 int slimpro_mbox_remove(struct platform_device *pdev) >>> +{ >>> + struct slimpro_mbox *smb = platform_get_drvdata(pdev); >>> + >>> + mbox_controller_unregister(&smb->mb_ctrl); >>> + 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, >>> + .remove = slimpro_mbox_remove, >>> + .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"); >>> -- >>> 1.9.1 >>> -- To unsubscribe from this list: send the line "unsubscribe devicetree" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
