Hi, A mistake in typo. > From: linux-acpi-owner@xxxxxxxxxxxxxxx [mailto:linux-acpi-owner@xxxxxxxxxxxxxxx] On Behalf Of Zheng, Lv > Sent: Thursday, September 04, 2014 12:36 PM > To: Ashwin Chaugule; arnd@xxxxxxxx > Cc: linux-acpi@xxxxxxxxxxxxxxx; linaro-acpi@xxxxxxxxxxxxxxxx; rjw@xxxxxxxxxxxxx; broonie@xxxxxxxxxx > Subject: RE: [PATCH v5 1/2] Mailbox: Add support for Platform Communication Channel > > Hi, > > > From: linux-acpi-owner@xxxxxxxxxxxxxxx [mailto:linux-acpi-owner@xxxxxxxxxxxxxxx] On Behalf Of Ashwin Chaugule > > Sent: Thursday, September 04, 2014 6:19 AM > > > > ACPI 5.0+ spec defines a generic mode of communication > > between the OS and a platform such as the BMC. This medium > > (PCC) is typically used by CPPC (ACPI CPU Performance management), > > RAS (ACPI reliability protocol) and MPST (ACPI Memory power > > states). > > > > This patch adds PCC support as a Mailbox Controller. > > > > Signed-off-by: Ashwin Chaugule <ashwin.chaugule@xxxxxxxxxx> > > --- > > drivers/mailbox/Kconfig | 12 ++ > > drivers/mailbox/Makefile | 2 + > > drivers/mailbox/mailbox.c | 4 - > > drivers/mailbox/pcc.c | 297 +++++++++++++++++++++++++++++++++++++ > > include/linux/mailbox_controller.h | 4 + > > 5 files changed, 315 insertions(+), 4 deletions(-) > > create mode 100644 drivers/mailbox/pcc.c > > > > diff --git a/drivers/mailbox/Kconfig b/drivers/mailbox/Kconfig > > index c8b5c13..e08cc83 100644 > > --- a/drivers/mailbox/Kconfig > > +++ b/drivers/mailbox/Kconfig > > @@ -50,4 +50,16 @@ config OMAP_MBOX_KFIFO_SIZE > > Specify the default size of mailbox's kfifo buffers (bytes). > > This can also be changed at runtime (via the mbox_kfifo_size > > module parameter). > > + > > +config PCC > > + bool "Platform Communication Channel Driver" > > + depends on ACPI > > + help > > + ACPI 5.0+ spec defines a generic mode of communication > > + between the OS and a platform such as the BMC. This medium > > + (PCC) is typically used by CPPC (ACPI CPU Performance management), > > + RAS (ACPI reliability protocol) and MPST (ACPI Memory power > > + states). Select this driver if your platform implements the > > + PCC clients mentioned above. > > + > > endif > > diff --git a/drivers/mailbox/Makefile b/drivers/mailbox/Makefile > > index 2fa343a..0b09d6f 100644 > > --- a/drivers/mailbox/Makefile > > +++ b/drivers/mailbox/Makefile > > @@ -9,3 +9,5 @@ obj-$(CONFIG_OMAP1_MBOX) += mailbox_omap1.o > > mailbox_omap1-objs := mailbox-omap1.o > > obj-$(CONFIG_OMAP2PLUS_MBOX) += mailbox_omap2.o > > mailbox_omap2-objs := mailbox-omap2.o > > + > > +obj-$(CONFIG_PCC) += pcc.o > > diff --git a/drivers/mailbox/mailbox.c b/drivers/mailbox/mailbox.c > > index 63ecc17..e07cfb0 100644 > > --- a/drivers/mailbox/mailbox.c > > +++ b/drivers/mailbox/mailbox.c > > @@ -21,10 +21,6 @@ > > #include <linux/mailbox_client.h> > > #include <linux/mailbox_controller.h> > > > > -#define TXDONE_BY_IRQ BIT(0) /* controller has remote RTR irq */ > > -#define TXDONE_BY_POLL BIT(1) /* controller can read status of last TX */ > > -#define TXDONE_BY_ACK BIT(2) /* S/W ACK recevied by Client ticks the TX */ > > - > > static LIST_HEAD(mbox_cons); > > static DEFINE_MUTEX(con_mutex); > > > > diff --git a/drivers/mailbox/pcc.c b/drivers/mailbox/pcc.c > > new file mode 100644 > > index 0000000..f910c96 > > --- /dev/null > > +++ b/drivers/mailbox/pcc.c > > @@ -0,0 +1,297 @@ > > +/* > > + * Copyright (C) 2014 Linaro Ltd. > > + * Author: Ashwin Chaugule <ashwin.chaugule@xxxxxxxxxx> > > + * > > + * 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. > > + * > > + */ > > + > > +#include <linux/acpi.h> > > +#include <linux/io.h> > > +#include <linux/uaccess.h> > > +#include <linux/init.h> > > +#include <linux/cpufreq.h> > > +#include <linux/delay.h> > > +#include <linux/ioctl.h> > > +#include <linux/vmalloc.h> > > +#include <linux/module.h> > > +#include <linux/mailbox_controller.h> > > +#include <linux/mailbox_client.h> > > +#include <linux/platform_device.h> > > + > > +#include <acpi/actbl.h> > > Please do not include this directly, it is already included by <linux/acpi.h> even when CONFIG is N. > See <linux/acpi.h> -> <acpi/acpi.h> -> <acpi/actbl.h> CONFIG should be CONFIG_ACPI. Sorry for the noise. Thanks -Lv > > Thanks and best regards > -Lv > > > + > > +#define MAX_PCC_SUBSPACES 256 > > +#define PCCS_SS_SIG_MAGIC 0x50434300 > > +#define PCC_CMD_COMPLETE 0x1 > > + > > +static struct mbox_chan pcc_mbox_chan[MAX_PCC_SUBSPACES]; > > +static struct mbox_controller pcc_mbox_ctrl = {}; > > + > > +struct mbox_chan *pcc_mbox_request_channel(struct mbox_client *cl, > > + int index) > > +{ > > + struct device *dev = pcc_mbox_ctrl.dev; > > + struct mbox_chan *chan; > > + unsigned long flags; > > + > > + /* > > + * Each PCC Subspace is a Mailbox Channel. > > + * The PCC Clients get their PCC Subspace ID > > + * from their own tables and pass it here. > > + * This returns a pointer to the PCC subspace > > + * for the Client to operate on. > > + */ > > + chan = &pcc_mbox_chan[index]; > > + > > + if (!chan || chan->cl || !try_module_get(dev->driver->owner)) { > > + dev_err(dev, "%s: PCC mailbox not free\n", __func__); > > + return ERR_PTR(-EBUSY); > > + } > > + > > + spin_lock_irqsave(&chan->lock, flags); > > + chan->msg_free = 0; > > + chan->msg_count = 0; > > + chan->active_req = NULL; > > + chan->cl = cl; > > + init_completion(&chan->tx_complete); > > + > > + if (chan->txdone_method == TXDONE_BY_POLL && cl->knows_txdone) > > + chan->txdone_method |= TXDONE_BY_ACK; > > + > > + spin_unlock_irqrestore(&chan->lock, flags); > > + > > + return chan; > > +} > > +EXPORT_SYMBOL_GPL(pcc_mbox_request_channel); > > + > > +void pcc_mbox_free_channel(struct mbox_chan *chan) > > +{ > > + unsigned long flags; > > + > > + if (!chan || !chan->cl) > > + return; > > + > > + spin_lock_irqsave(&chan->lock, flags); > > + chan->cl = NULL; > > + chan->active_req = NULL; > > + if (chan->txdone_method == (TXDONE_BY_POLL | TXDONE_BY_ACK)) > > + chan->txdone_method = TXDONE_BY_POLL; > > + > > + module_put(chan->mbox->dev->driver->owner); > > + spin_unlock_irqrestore(&chan->lock, flags); > > +} > > +EXPORT_SYMBOL_GPL(pcc_mbox_free_channel); > > + > > +static bool pcc_tx_done(struct mbox_chan *chan) > > +{ > > + struct acpi_pcct_subspace *pcct_ss = chan->con_priv; > > + struct acpi_pcct_shared_memory *generic_comm_base = > > + (struct acpi_pcct_shared_memory *) pcct_ss->base_address; > > + u16 cmd_delay = pcct_ss->min_turnaround_time; > > + > > + /* Wait for Platform to consume. */ > > + while (!(ioread16(&generic_comm_base->status) & PCC_CMD_COMPLETE)) > > + udelay(cmd_delay); > > + > > + return true; > > +} > > + > > +static int get_subspace_id(struct mbox_chan *chan) > > +{ > > + unsigned int i; > > + > > + for (i = 0; i < pcc_mbox_ctrl.num_chans; i++) { > > + if (chan == &pcc_mbox_chan[i]) > > + return i; > > + } > > + > > + return -ENOENT; > > +} > > + > > +/* Channel lock is already held by mbox controller code. */ > > +static int pcc_send_data(struct mbox_chan *chan, void *data) > > +{ > > + struct acpi_pcct_subspace *pcct_ss = chan->con_priv; > > + struct acpi_pcct_shared_memory *generic_comm_base = > > + (struct acpi_pcct_shared_memory *) pcct_ss->base_address; > > + struct acpi_generic_address doorbell; > > + u64 doorbell_preserve; > > + u64 doorbell_val; > > + u64 doorbell_write; > > + u16 cmd = 0; > > + u16 ss_idx = -1; > > + int ret = 0; > > + > > + /* Get PCC CMD */ > > + ret = kstrtou16((char*)data, 0, &cmd); > > + if (ret < 0) { > > + pr_err("Err while converting PCC CMD to u16: %d\n", ret); > > + goto out_err; > > + } > > + > > + ss_idx = get_subspace_id(chan); > > + > > + if (ss_idx < 0) { > > + pr_err("Invalid Subspace ID from PCC client\n"); > > + ret = ss_idx; > > + goto out_err; > > + } > > + > > + doorbell = pcct_ss->doorbell_register; > > + doorbell_preserve = pcct_ss->preserve_mask; > > + doorbell_write = pcct_ss->write_mask; > > + > > + /* Write to the shared comm region. */ > > + iowrite16(cmd, &generic_comm_base->command); > > + > > + /* Write Subspace MAGIC value so platform can identify destination. */ > > + iowrite32((PCCS_SS_SIG_MAGIC | ss_idx), &generic_comm_base->signature); > > + > > + /* Flip CMD COMPLETE bit */ > > + iowrite16(0, &generic_comm_base->status); > > + > > + /* Sync notification from OSPM to Platform. */ > > + acpi_read(&doorbell_val, &doorbell); > > + acpi_write((doorbell_val & doorbell_preserve) | doorbell_write, > > + &doorbell); > > + > > +out_err: > > + return ret; > > +} > > + > > +static struct mbox_chan_ops pcc_chan_ops = { > > + .send_data = pcc_send_data, > > + .last_tx_done = pcc_tx_done, > > +}; > > + > > +static int parse_pcc_subspace(struct acpi_subtable_header *header, > > + const unsigned long end) > > +{ > > + struct acpi_pcct_subspace *pcct_ss; > > + > > + if (pcc_mbox_ctrl.num_chans <= MAX_PCC_SUBSPACES) { > > + pcct_ss = (struct acpi_pcct_subspace *) header; > > + > > + if (pcct_ss->header.type != ACPI_PCCT_TYPE_GENERIC_SUBSPACE) { > > + pr_err("Incorrect PCC Subspace type detected\n"); > > + return -EINVAL; > > + } > > + > > + /* New mbox channel entry for each PCC subspace detected. */ > > + pcc_mbox_chan[pcc_mbox_ctrl.num_chans].con_priv = pcct_ss; > > + pcc_mbox_ctrl.num_chans++; > > + > > + } else { > > + pr_err("No more space for PCC subspaces.\n"); > > + return -ENOSPC; > > + } > > + > > + return 0; > > +} > > + > > +/* > > + * Create a virtual device to back the PCCT, so > > + * that the generic Mailbox framework can do its > > + * ref counting. > > + */ > > +struct platform_device pcc_pdev = { > > + .name = "PCCT", > > +}; > > + > > +static int __init acpi_pcc_probe(void) > > +{ > > + acpi_status status = AE_OK; > > + acpi_size pcct_tbl_header_size; > > + struct acpi_table_pcct *pcct_tbl; > > + int ret; > > + > > + /* Search for PCCT */ > > + status = acpi_get_table_with_size(ACPI_SIG_PCCT, 0, > > + (struct acpi_table_header **)&pcct_tbl, > > + &pcct_tbl_header_size); > > + > > + if (ACPI_SUCCESS(status) && !pcct_tbl) { > > + pr_warn("PCCT header not found.\n"); > > + status = AE_NOT_FOUND; > > + goto out_err; > > + } > > + > > + status = acpi_table_parse_entries(ACPI_SIG_PCCT, > > + sizeof(struct acpi_table_pcct), > > + ACPI_PCCT_TYPE_GENERIC_SUBSPACE, > > + parse_pcc_subspace, MAX_PCC_SUBSPACES); > > + > > + if (ACPI_SUCCESS(status)) > > + pr_err("Error parsing PCC subspaces from PCCT\n"); > > + > > + pr_info("Detected %d PCC Subspaces\n", pcc_mbox_ctrl.num_chans); > > + > > + pcc_mbox_ctrl.chans = pcc_mbox_chan; > > + pcc_mbox_ctrl.ops = &pcc_chan_ops; > > + pcc_mbox_ctrl.txdone_poll = true; > > + pcc_mbox_ctrl.txpoll_period = 1; > > + > > + ret = platform_device_register(&pcc_pdev); > > + > > + if (ret) { > > + pr_err ("Err registering PCC platform device\n"); > > + return -ENODEV; > > + } > > + > > +out_err: > > + return ACPI_SUCCESS(status) ? 1 : 0; > > +} > > + > > +static int pcc_mbox_probe(struct platform_device *pdev) > > +{ > > + int ret = 0; > > + > > + pcc_mbox_ctrl.dev = &pdev->dev; > > + > > + pr_info("Registering PCC driver as Mailbox controller\n"); > > + ret = mbox_controller_register(&pcc_mbox_ctrl); > > + > > + if (ret) { > > + pr_err("Err registering PCC as Mailbox controller: %d\n", ret); > > + ret = -ENODEV; > > + } > > + > > + return ret; > > +} > > + > > +struct platform_driver pcc_mbox_driver = { > > + .probe = pcc_mbox_probe, > > + .driver = { > > + .name = "PCCT", > > + .owner = THIS_MODULE, > > + }, > > +}; > > + > > +static int __init pcc_init(void) > > +{ > > + int ret; > > + > > + if (acpi_disabled) > > + return -ENODEV; > > + > > + /* Check if PCC support is available. */ > > + ret = acpi_pcc_probe(); > > + > > + if (ret) { > > + pr_debug("PCC probe failed.\n"); > > + return -EINVAL; > > + } > > + > > + return platform_driver_register(&pcc_mbox_driver); > > +} > > + > > +device_initcall(pcc_init); > > diff --git a/include/linux/mailbox_controller.h b/include/linux/mailbox_controller.h > > index 9ee195b..956cc06 100644 > > --- a/include/linux/mailbox_controller.h > > +++ b/include/linux/mailbox_controller.h > > @@ -15,6 +15,10 @@ > > > > struct mbox_chan; > > > > +#define TXDONE_BY_IRQ BIT(0) /* controller has remote RTR irq */ > > +#define TXDONE_BY_POLL BIT(1) /* controller can read status of last TX */ > > +#define TXDONE_BY_ACK BIT(2) /* S/W ACK recevied by Client ticks the TX */ > > + > > /** > > * struct mbox_chan_ops - methods to control mailbox channels > > * @send_data: The API asks the MBOX controller driver, in atomic > > -- > > 1.9.1 > > > > -- > > To unsubscribe from this list: send the line "unsubscribe linux-acpi" in > > the body of a message to majordomo@xxxxxxxxxxxxxxx > > More majordomo info at http://vger.kernel.org/majordomo-info.html > -- > To unsubscribe from this list: send the line "unsubscribe linux-acpi" in > the body of a message to majordomo@xxxxxxxxxxxxxxx > More majordomo info at http://vger.kernel.org/majordomo-info.html -- To unsubscribe from this list: send the line "unsubscribe linux-acpi" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
