> -----Original Message----- > From: Pan Lijun-B44306 > Sent: Thursday, October 29, 2015 6:55 PM > To: Wood Scott-B07421 > Cc: gregkh@linuxfoundation.org; arnd@arndb.de; devel@driverdev.osuosl.org; > linux-kernel@vger.kernel.org; Yoder Stuart-B08248 > ; katz Itai-RM05202 ; > Rivera Jose-B46482 ; Li Yang-Leo-R58472 > ; agraf@suse.de; Hamciuc Bogdan-BHAMCIU1 > ; Marginean Alexandru-R89243 > ; Sharma Bhupesh-B45370 > ; Erez Nir-RM30794 > ; Schmitt Richard-B43082 > ; dan.carpenter@oracle.com > Subject: RE: [PATCH 5/5] staging: fsl-mc: Management Complex restool driver > > > > > -----Original Message----- > > From: Wood Scott-B07421 > > Sent: Tuesday, October 27, 2015 12:17 AM > > To: Pan Lijun-B44306 > > Cc: gregkh@linuxfoundation.org; arnd@arndb.de; > > devel@driverdev.osuosl.org; linux-kernel@vger.kernel.org; Yoder > > Stuart-B08248 ; katz Itai-RM05202 > > ; Rivera Jose-B46482 > > ; Li Yang-Leo-R58472 > > ; agraf@suse.de; Hamciuc Bogdan-BHAMCIU1 > > ; Marginean Alexandru-R89243 > > ; Sharma Bhupesh-B45370 > > ; Erez Nir-RM30794 > > ; Schmitt Richard-B43082 > > ; dan.carpenter@oracle.com > > Subject: Re: [PATCH 5/5] staging: fsl-mc: Management Complex restool > > driver > > > > On Sun, 2015-10-25 at 17:41 -0500, Lijun Pan wrote: > > > The kernel support for the restool (a user space resource management > > > tool) is a driver for the /dev/dprc.N device file. > > > Its purpose is to provide an ioctl interface, which the restool uses > > > to interact with the MC bus driver and with the MC firmware. > > > We allocate a dpmcp at driver initialization, and keep that dpmcp > > > until driver exit. > > > We use that dpmcp by default. > > > If that dpmcp is in use, we create another portal at run time and > > > destroy the newly created portal after use. > > > The ioctl RESTOOL_SEND_MC_COMMAND sends user space command to > fsl- > > mc > > > bus and utilizes the fsl-mc bus to communicate with MC firmware. > > > The ioctl RESTOOL_DPRC_SYNC request the mc-bus launch objects scan > > > under root dprc. > > > In order to support multiple root dprc, we utilize the bus notify > > > mechanism to scan fsl_mc_bus_type for the newly added root dprc. > > > After discovering the root dprc, it creates a miscdevice /dev/dprc.N > > > to associate with this root dprc. > > > > > > Signed-off-by: Lijun Pan > > > --- > > > drivers/staging/fsl-mc/bus/Kconfig | 7 +- > > > drivers/staging/fsl-mc/bus/Makefile | 3 + > > > drivers/staging/fsl-mc/bus/mc-ioctl.h | 24 ++ > > > drivers/staging/fsl-mc/bus/mc-restool.c | 488 > > > ++++++++++++++++++++++++++++++++ > > > 4 files changed, 521 insertions(+), 1 deletion(-) create mode > > > 100644 drivers/staging/fsl-mc/bus/mc-ioctl.h > > > create mode 100644 drivers/staging/fsl-mc/bus/mc-restool.c > > > > > > diff --git a/drivers/staging/fsl-mc/bus/Kconfig > > > b/drivers/staging/fsl- mc/bus/Kconfig index 0d779d9..39c6ef9 100644 > > > --- a/drivers/staging/fsl-mc/bus/Kconfig > > > +++ b/drivers/staging/fsl-mc/bus/Kconfig > > > @@ -21,4 +21,9 @@ config FSL_MC_BUS > > > Only enable this option when building the kernel for > > > Freescale QorQIQ LS2xxxx SoCs. > > > > > > - > > > +config FSL_MC_RESTOOL > > > + tristate "Freescale Management Complex (MC) restool driver" > > > + depends on FSL_MC_BUS > > > + help > > > + Driver that provides kernel support for the Freescale Management > > > + Complex resource manager user-space tool. > > > diff --git a/drivers/staging/fsl-mc/bus/Makefile > > > b/drivers/staging/fsl- mc/bus/Makefile index 25433a9..28b5fc0 100644 > > > --- a/drivers/staging/fsl-mc/bus/Makefile > > > +++ b/drivers/staging/fsl-mc/bus/Makefile > > > @@ -15,3 +15,6 @@ mc-bus-driver-objs := mc-bus.o \ > > > mc-allocator.o \ > > > dpmcp.o \ > > > dpbp.o > > > + > > > +# MC restool kernel support > > > +obj-$(CONFIG_FSL_MC_RESTOOL) += mc-restool.o > > > diff --git a/drivers/staging/fsl-mc/bus/mc-ioctl.h > > > b/drivers/staging/fsl- mc/bus/mc-ioctl.h new file mode 100644 index > > > 0000000..e52f907 > > > --- /dev/null > > > +++ b/drivers/staging/fsl-mc/bus/mc-ioctl.h > > > @@ -0,0 +1,24 @@ > > > +/* > > > + * Freescale Management Complex (MC) ioclt interface > > > > ioctl > > > > > + * > > > + * Copyright (C) 2014 Freescale Semiconductor, Inc. > > > + * Author: Lijun Pan > > > + * > > > + * This file is licensed under the terms of the GNU General Public > > > + * License version 2. This program is licensed "as is" without any > > > + * warranty of any kind, whether express or implied. > > > + */ > > > +#ifndef _FSL_MC_IOCTL_H_ > > > +#define _FSL_MC_IOCTL_H_ > > > + > > > +#include > > > + > > > +#define RESTOOL_IOCTL_TYPE 'R' > > > + > > > +#define RESTOOL_DPRC_SYNC \ > > > + _IO(RESTOOL_IOCTL_TYPE, 0x2) > > > + > > > +#define RESTOOL_SEND_MC_COMMAND \ > > > + _IOWR(RESTOOL_IOCTL_TYPE, 0x4, struct mc_command) > > > > Look at Documentation/ioctl/ioctl-number.txt and reserve a range within 'R' > > that doesn't conflict. > > > > Add thorough documentation of this API. > > What path do you recommend me to put documentation of this API? Is Documentation/misc-devices/mc-restool.txt the correct location? > > > > I'm not sure how it's usually handled with staging drivers, but > > eventually this will need to move to an appropriate uapi header. Is > > this functionality even needed before the driver comes out of staging? > > I don't see "userspace restool support" in drivers/staging/fsl-mc/TODO. > > > > Don't reference struct mc_command without including the header that > > defines it. > > > > > +#endif /* _FSL_MC_IOCTL_H_ */ > > > diff --git a/drivers/staging/fsl-mc/bus/mc-restool.c > > > b/drivers/staging/fsl- mc/bus/mc-restool.c new file mode 100644 > > > index > > > 0000000..a219172 > > > --- /dev/null > > > +++ b/drivers/staging/fsl-mc/bus/mc-restool.c > > > @@ -0,0 +1,488 @@ > > > +/* > > > + * Freescale Management Complex (MC) restool driver > > > + * > > > + * Copyright (C) 2014 Freescale Semiconductor, Inc. > > > + * Author: Lijun Pan > > > + * > > > + * This file is licensed under the terms of the GNU General Public > > > + * License version 2. This program is licensed "as is" without any > > > + * warranty of any kind, whether express or implied. > > > + */ > > > + > > > +#include "../include/mc-private.h" > > > +#include > > > +#include > > > +#include > > > +#include > > > +#include > > > +#include > > > +#include > > > +#include > > > +#include "mc-ioctl.h" > > > +#include "../include/mc-sys.h" > > > +#include "../include/mc-cmd.h" > > > +#include "../include/dpmng.h" > > > + > > > +/** > > > + * Maximum number of DPRCs that can be opened at the same time */ > > > +#define MAX_DPRC_HANDLES 64 > > > + > > > +/** > > > + * restool_misc - information associated with the newly added > > > +miscdevice > > > + * @misc: newly created miscdevice associated with root dprc > > > + * @miscdevt: device id of this miscdevice > > > + * @list: a linked list node representing this miscdevcie > > > + * @static_mc_io: pointer to the static MC I/O object used by the > > > +restool > > > + * @dynamic_instance_count: number of dynamically created instances > > > + * @static_instance_in_use: static instance is in use or not > > > + * @mutex: mutex lock to serialze the operations > > > + * @dev: root dprc associated with this miscdevice */ struct > > > +restool_misc { > > > + struct miscdevice misc; > > > + dev_t miscdevt; > > > + struct list_head list; > > > + struct fsl_mc_io *static_mc_io; > > > + uint32_t dynamic_instance_count; > > > + bool static_instance_in_use; > > > + struct mutex mutex; > > > + struct device *dev; > > > +}; > > > + > > > +/* > > > + * initialize a global list to link all > > > + * the miscdevice nodes (struct restool_misc) */ > > > +LIST_HEAD(misc_list); > > > > static > > > > > +static int fsl_mc_restool_dev_open(struct inode *inode, struct file > > > +*filep) { > > > + struct fsl_mc_device *root_mc_dev; > > > + int error = 0; > > > + struct fsl_mc_io *dynamic_mc_io = NULL; > > > + struct restool_misc *restool_misc; > > > + struct restool_misc *restool_misc_cursor; > > > + > > > + pr_debug("%s: inode's dev_t == %u\n", __func__, > > > + inode->i_rdev); > > > + > > > + list_for_each_entry(restool_misc_cursor, &misc_list, list) { > > > + if (restool_misc_cursor->miscdevt == inode->i_rdev) { > > > + pr_debug("%s: Found the restool_misc\n", __func__); > > > + restool_misc = restool_misc_cursor; > > > + break; > > > + } > > > + } > > > > No synchronization on the list? > > > > > + > > > + if (!restool_misc) > > > + return -EINVAL; > > > + > > > + if (WARN_ON(restool_misc->dev == NULL)) > > > + return -EINVAL; > > > + > > > + mutex_lock(&restool_misc->mutex); > > > + > > > + if (!restool_misc->static_instance_in_use) { > > > + restool_misc->static_instance_in_use = true; > > > + filep->private_data = restool_misc->static_mc_io; > > > + } else { > > > + dynamic_mc_io = kzalloc(sizeof(struct fsl_mc_io), GFP_KERNEL); > > > + if (dynamic_mc_io == NULL) { > > > + error = -ENOMEM; > > > + goto error; > > > + } > > > + > > > + root_mc_dev = to_fsl_mc_device(restool_misc->dev); > > > + error = fsl_mc_portal_allocate(root_mc_dev, 0, &dynamic_mc_io); > > > + if (error < 0) { > > > + pr_err("Not able to allocate MC portal\n"); > > > + goto error; > > > + } > > > + ++restool_misc->dynamic_instance_count; > > > + filep->private_data = dynamic_mc_io; > > > + } > > > > Why is the first user handled differently from subsequent users? Does > > each user really need its own portal, or can you just synchronize access? > > First user get the statically allocated portal. > Second user need to dynamically allocate one. > Some operations may take a long time (say 1 second) in MC object creation. > In order to support asynchronous portal operation, We allocate portal for each > user. > > Lijun > > > > > -Scott {.n++%ݶw{.n+{G{ayʇڙ,jfhz_(階ݢj"mG?&~iOzv^m ?I