From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from ipmail07.adl2.internode.on.net (ipmail07.adl2.internode.on.net [150.101.137.131]) by lists.ozlabs.org (Postfix) with ESMTP id 3tH9Gk24l9zDvWr for ; Mon, 14 Nov 2016 10:44:14 +1100 (AEDT) X-IronPort-Anti-Spam-Filtered: true X-IronPort-Anti-Spam-Result: A2BXAwAs+ihYfQpSY3pcHAEBBAEBCgEBgyYLAQEBAQF3gQCFKJ8eh2yKZYQWIIJNgzYCgl8BAgEBAQEBAhMBARYvMIRhAQEBBCcTPxALFQMJFRAPARE2GYhHAxaxHD2HJg2EEAEBAQcCASSLFoJIgWoWhWEFiEmGFwyBNYlYEzWGPIZehCqBCE+HZIV+iR2EJ4QKgTwRCxyDIRyBcSo0AYdBAQEB Received: from static-82-10.transact.net.au (HELO new-mexico.localnet) ([122.99.82.10]) by ipmail07.adl2.internode.on.net with ESMTP; 14 Nov 2016 10:14:03 +1030 From: Alistair Popple To: openbmc@lists.ozlabs.org Cc: christopher.lee.bostic@gmail.com, xxpetri@de.ibm.com, zahrens@us.ibm.com Subject: Re: [PATCH linux v6 18/18] drivers/fsi: Add SCOM FSI client device driver Date: Mon, 14 Nov 2016 10:44:01 +1100 Message-ID: <1518766.oRRvze06Vl@new-mexico> User-Agent: KMail/4.14.1 (Linux/4.2.0-0.bpo.1-amd64; KDE/4.14.2; x86_64; ; ) In-Reply-To: <1477865379-11566-19-git-send-email-christopher.lee.bostic@gmail.com> References: <1477865379-11566-1-git-send-email-christopher.lee.bostic@gmail.com> <1477865379-11566-19-git-send-email-christopher.lee.bostic@gmail.com> MIME-Version: 1.0 Content-Transfer-Encoding: 7Bit Content-Type: text/plain; charset="us-ascii" X-BeenThere: openbmc@lists.ozlabs.org X-Mailman-Version: 2.1.23 Precedence: list List-Id: Development list for OpenBMC List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Sun, 13 Nov 2016 23:44:14 -0000 Hi Chris, Is there a similar device driver for the CFAM/FSI that I missed? That is will there be a chardev for read/writing FSI addresses directly (ie. a chardev to call fsi_device_read/write)? Probably not critical for an initial release but we will need one at some point as I'm pretty sure the cronus server for example has get/putcfam commands as some registers aren't available via SCOM. Regards, Alistair On Sun, 30 Oct 2016 05:09:20 PM christopher.lee.bostic@gmail.com wrote: > From: Chris Bostic > > Create a simple SCOM engine device driver that reads and writes > across an FSI bus. > > Signed-off-by: Chris Bostic > > --- > > V4 - Add put_scom and get_scom operations > > V5 - Add character device registration and fill in read/write > syscalls. > > V6 - Add multi scom engine support. Add list of devices. > Use file private data to store and hand off scom structures. > > - Add lseek, open, close > > - Remove data/address structure to pass from user space to > kernel. Use offset provided by read/write and pass data > > - Added list setup in init and so did not add the macro > module_fsi_driver > > - Global structs made static where possible. > > - Change from char dev to use misc device api as shown > in examples from Jeremy Kere. > --- > drivers/fsi/Kconfig | 6 ++ > drivers/fsi/Makefile | 1 + > drivers/fsi/fsi-scom.c | 238 +++++++++++++++++++++++++++++++++++++++++++++++++ > 3 files changed, 245 insertions(+) > create mode 100644 drivers/fsi/fsi-scom.c > > diff --git a/drivers/fsi/Kconfig b/drivers/fsi/Kconfig > index b21fe3c..1fa9bc0 100644 > --- a/drivers/fsi/Kconfig > +++ b/drivers/fsi/Kconfig > @@ -23,6 +23,12 @@ config FSI_MASTER_GPIO > depends on FSI > ---help--- > This option enables a FSI master driver using GPIO lines. > + > +config FSI_SCOM > + tristate "SCOM FSI client" > + depends on FSI > + ---help--- > + This option enables the SCOM FSI client device driver. > endif > > endmenu > diff --git a/drivers/fsi/Makefile b/drivers/fsi/Makefile > index 2021ce5..3e31d9a 100644 > --- a/drivers/fsi/Makefile > +++ b/drivers/fsi/Makefile > @@ -2,3 +2,4 @@ > obj-$(CONFIG_FSI) += fsi-core.o > obj-$(CONFIG_FSI_MASTER_FAKE) += fsi-master-fake.o > obj-$(CONFIG_FSI_MASTER_GPIO) += fsi-master-gpio.o > +obj-$(CONFIG_FSI_SCOM) += fsi-scom.o > diff --git a/drivers/fsi/fsi-scom.c b/drivers/fsi/fsi-scom.c > new file mode 100644 > index 0000000..27be082 > --- /dev/null > +++ b/drivers/fsi/fsi-scom.c > @@ -0,0 +1,238 @@ > +/* > + * SCOM FSI Client device driver > + * > + * Copyright (C) IBM Corporation 2016 > + * > + * This program is free software; you can redistribute it and/or modify > + * it under the terms of the GNU General Public License version 2 as > + * published by the Free Software Foundation. > + * > + * This program is distributed in the hope that it will be useful, > + * but WITHOUT ANY WARRANTY; without even the implied warranty of > + * MERGCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the > + * GNU General Public License for more details. > + */ > + > +#include > +#include > +#include > +#include > +#include > +#include > +#include > +#include > +#include > + > +#define FSI_ENGID_SCOM 0x5 > + > +#define SCOM_FSI2PIB_DELAY 50 > + > +/* SCOM engine register set */ > +#define SCOM_DATA0_REG 0x00 > +#define SCOM_DATA1_REG 0x04 > +#define SCOM_CMD_REG 0x08 > +#define SCOM_RESET_REG 0x1C > + > +#define SCOM_RESET_CMD 0x80000000 > +#define SCOM_WRITE_CMD 0x80000000 > + > +struct scom_device { > + struct list_head link; > + struct fsi_device *fsi_dev; > + struct miscdevice mdev; > + char name[32]; > +}; > + > +#define to_scom_dev(x) container_of((x), struct scom_device, mdev) > + > +static struct list_head scom_devices; > +static atomic_t scom_idx = ATOMIC_INIT(0); > +static int scom_probe(struct device *); > + > +static int put_scom(struct scom_device *scom_dev, uint64_t value, > + uint32_t addr) > +{ > + int rc; > + uint32_t data = SCOM_RESET_CMD; > + > + rc = fsi_device_write(scom_dev->fsi_dev, SCOM_RESET_REG, &data, > + sizeof(uint32_t)); > + if (rc) > + return rc; > + > + data = (value >> 32) & 0xffffffff; > + rc = fsi_device_write(scom_dev->fsi_dev, SCOM_DATA0_REG, &data, > + sizeof(uint32_t)); > + if (rc) > + return rc; > + > + data = value & 0xffffffff; > + rc = fsi_device_write(scom_dev->fsi_dev, SCOM_DATA1_REG, &data, > + sizeof(uint32_t)); > + if (rc) > + return rc; > + > + data = SCOM_WRITE_CMD | addr; > + return fsi_device_write(scom_dev->fsi_dev, SCOM_CMD_REG, &data, > + sizeof(uint32_t)); > +} > + > +static int get_scom(struct scom_device *scom_dev, uint64_t *value, > + uint32_t addr) > +{ > + uint32_t result, data; > + int rc; > + > + udelay(SCOM_FSI2PIB_DELAY); > + > + data = addr; > + rc = fsi_device_write(scom_dev->fsi_dev, SCOM_CMD_REG, &data, > + sizeof(uint32_t)); > + if (rc) > + return rc; > + > + rc = fsi_device_read(scom_dev->fsi_dev, SCOM_DATA0_REG, &result, > + sizeof(uint32_t)); > + if (rc) > + return rc; > + > + *value |= (uint64_t) result << 32; > + rc = fsi_device_read(scom_dev->fsi_dev, SCOM_DATA1_REG, &result, > + sizeof(uint32_t)); > + if (rc) > + return rc; > + > + *value |= result; > + > + return 0; > +} > + > +static loff_t scom_llseek(struct file *filep, loff_t offset, int whence) > +{ > + if (whence != 0) /* SEEK_SET */ > + return -EINVAL; > + > + filep->f_pos = offset; > + return offset; > +} > + > +static ssize_t scom_read(struct file *filep, char __user *buf, size_t len, > + loff_t *offset) > +{ > + int rc = 0; > + struct miscdevice *mdev = > + (struct miscdevice *)filep->private_data; > + struct scom_device *scom = to_scom_dev(mdev); > + struct device *dev = &scom->fsi_dev->dev; > + uint64_t val; > + > + if (len != sizeof(uint64_t)) > + return -EINVAL; > + > + rc = get_scom(scom, &val, *offset); > + if (rc) { > + dev_dbg(dev, "get_scom fail:%d\n", rc); > + return rc; > + } > + > + rc = copy_to_user(buf, &val, len); > + if (rc) > + dev_dbg(dev, "copy to user failed:%d\n", rc); > + > + return rc ? rc : len; > +} > + > +static ssize_t scom_write(struct file *filep, const char __user *buf, > + size_t len, loff_t *offset) > +{ > + int rc = 0; > + struct miscdevice *mdev = > + (struct miscdevice *)filep->private_data; > + struct scom_device *scom = to_scom_dev(mdev); > + struct device *dev = &scom->fsi_dev->dev; > + uint64_t val; > + > + if (len != sizeof(uint64_t)) > + return -EINVAL; > + > + rc = copy_from_user(&val, buf, len); > + if (rc) { > + dev_dbg(dev, "copy from user failed:%d\n", rc); > + return -EINVAL; > + } > + > + rc = put_scom(scom, val, *offset); > + if (rc) > + dev_dbg(dev, "put_scom failed with:%d\n", rc); > + > + > + return rc ? rc : len; > +} > + > +static const struct file_operations scom_fops = { > + .owner = THIS_MODULE, > + .llseek = scom_llseek, > + .read = scom_read, > + .write = scom_write, > +}; > + > +static int scom_probe(struct device *dev) > +{ > + struct fsi_device *fsi_dev = to_fsi_dev(dev); > + struct scom_device *scom = NULL; > + > + scom = devm_kzalloc(dev, sizeof(*scom), GFP_KERNEL); > + if (!scom) > + return -ENOMEM; > + > + snprintf(scom->name, sizeof(scom->name), > + "scom%d", atomic_inc_return(&scom_idx)); > + scom->fsi_dev = fsi_dev; > + scom->mdev.minor = MISC_DYNAMIC_MINOR; > + scom->mdev.fops = &scom_fops; > + scom->mdev.name = scom->name; > + scom->mdev.parent = dev; > + list_add(&scom->link, &scom_devices); > + > + return misc_register(&scom->mdev); > +} > + > +static struct fsi_device_id scom_ids[] = { > + { > + .engine_type = FSI_ENGID_SCOM, > + .version = FSI_VERSION_ANY, > + }, > + { 0 } > +}; > + > +static struct fsi_driver scom_drv = { > + .id_table = scom_ids, > + .drv = { > + .name = "scom", > + .bus = &fsi_bus_type, > + .probe = scom_probe, > + } > +}; > + > +static int scom_init(void) > +{ > + INIT_LIST_HEAD(&scom_devices); > + return fsi_driver_register(&scom_drv); > +} > + > +static void scom_exit(void) > +{ > + struct list_head *pos; > + struct scom_device *scom = NULL; > + > + list_for_each(pos, &scom_devices) { > + scom = list_entry(pos, struct scom_device, link); > + misc_deregister(&scom->mdev); > + devm_kfree(&scom->fsi_dev->dev, scom); > + } > + fsi_driver_unregister(&scom_drv); > +} > + > +module_init(scom_init); > +module_exit(scom_exit); > +MODULE_LICENSE("GPL"); >