| Message ID | 20230214212316.3309053-1-quic_eberman@quicinc.com (mailing list archive) |
|---|---|
| State | Superseded |
| Headers | show |
| Series | Drivers for Gunyah hypervisor | expand |
Hi Elliot,
Thank you for the patch! Yet something to improve:
[auto build test ERROR on 3ebb0ac55efaf1d0fb1b106f852c114e5021f7eb]
url: https://github.com/intel-lab-lkp/linux/commits/Elliot-Berman/docs-gunyah-Introduce-Gunyah-Hypervisor/20230215-055721
base: 3ebb0ac55efaf1d0fb1b106f852c114e5021f7eb
patch link: https://lore.kernel.org/r/20230214212316.3309053-1-quic_eberman%40quicinc.com
patch subject: [PATCH v10 07/26] mailbox: Add Gunyah message queue mailbox
config: arm64-allyesconfig (https://download.01.org/0day-ci/archive/20230216/202302161137.mfophRBY-lkp@intel.com/config)
compiler: aarch64-linux-gcc (GCC) 12.1.0
reproduce (this is a W=1 build):
wget https://raw.githubusercontent.com/intel/lkp-tests/master/sbin/make.cross -O ~/bin/make.cross
chmod +x ~/bin/make.cross
# https://github.com/intel-lab-lkp/linux/commit/b427188cd418632da7b26f283f5d2c668038186f
git remote add linux-review https://github.com/intel-lab-lkp/linux
git fetch --no-tags linux-review Elliot-Berman/docs-gunyah-Introduce-Gunyah-Hypervisor/20230215-055721
git checkout b427188cd418632da7b26f283f5d2c668038186f
# save the config file
mkdir build_dir && cp config build_dir/.config
COMPILER_INSTALL_PATH=$HOME/0day COMPILER=gcc-12.1.0 make.cross W=1 O=build_dir ARCH=arm64 olddefconfig
COMPILER_INSTALL_PATH=$HOME/0day COMPILER=gcc-12.1.0 make.cross W=1 O=build_dir ARCH=arm64 SHELL=/bin/bash drivers/
If you fix the issue, kindly add following tag where applicable
| Reported-by: kernel test robot <lkp@intel.com>
| Link: https://lore.kernel.org/oe-kbuild-all/202302161137.mfophRBY-lkp@intel.com/
All errors (new ones prefixed by >>):
drivers/mailbox/gunyah-msgq.c: In function 'gh_msgq_init':
>> drivers/mailbox/gunyah-msgq.c:180:15: error: implicit declaration of function 'mbox_bind_client' [-Werror=implicit-function-declaration]
180 | ret = mbox_bind_client(gh_msgq_chan(msgq), cl);
| ^~~~~~~~~~~~~~~~
cc1: some warnings being treated as errors
vim +/mbox_bind_client +180 drivers/mailbox/gunyah-msgq.c
110
111 /**
112 * gh_msgq_init() - Initialize a Gunyah message queue with an mbox_client
113 * @parent: optional, device parent used for the mailbox controller
114 * @msgq: Pointer to the gh_msgq to initialize
115 * @cl: A mailbox client to bind to the mailbox channel that the message queue creates
116 * @tx_ghrsc: optional, the transmission side of the message queue
117 * @rx_ghrsc: optional, the receiving side of the message queue
118 *
119 * At least one of tx_ghrsc and rx_ghrsc should be not NULL. Most message queue use cases come with
120 * a pair of message queues to facilitate bidirectional communication. When tx_ghrsc is set,
121 * the client can send messages with mbox_send_message(gh_msgq_chan(msgq), msg). When rx_ghrsc
122 * is set, the mbox_client should register an .rx_callback() and the message queue driver will
123 * push all available messages upon receiving the RX ready interrupt. The messages should be
124 * consumed or copied by the client right away as the gh_msgq_rx_data will be replaced/destroyed
125 * after the callback.
126 *
127 * Returns - 0 on success, negative otherwise
128 */
129 int gh_msgq_init(struct device *parent, struct gh_msgq *msgq, struct mbox_client *cl,
130 struct gunyah_resource *tx_ghrsc, struct gunyah_resource *rx_ghrsc)
131 {
132 int ret;
133
134 /* Must have at least a tx_ghrsc or rx_ghrsc and that they are the right device types */
135 if ((!tx_ghrsc && !rx_ghrsc) ||
136 (tx_ghrsc && tx_ghrsc->type != GUNYAH_RESOURCE_TYPE_MSGQ_TX) ||
137 (rx_ghrsc && rx_ghrsc->type != GUNYAH_RESOURCE_TYPE_MSGQ_RX))
138 return -EINVAL;
139
140 if (gh_api_version() != GUNYAH_API_V1) {
141 pr_err("Unrecognized gunyah version: %u. Currently supported: %d\n",
142 gh_api_version(), GUNYAH_API_V1);
143 return -EOPNOTSUPP;
144 }
145
146 if (!gh_api_has_feature(GH_API_FEATURE_MSGQUEUE))
147 return -EOPNOTSUPP;
148
149 msgq->tx_ghrsc = tx_ghrsc;
150 msgq->rx_ghrsc = rx_ghrsc;
151
152 msgq->mbox.dev = parent;
153 msgq->mbox.ops = &gh_msgq_ops;
154 msgq->mbox.num_chans = 1;
155 msgq->mbox.txdone_irq = true;
156 msgq->mbox.chans = kcalloc(msgq->mbox.num_chans, sizeof(*msgq->mbox.chans), GFP_KERNEL);
157 if (!msgq->mbox.chans)
158 return -ENOMEM;
159
160 if (msgq->tx_ghrsc) {
161 ret = request_irq(msgq->tx_ghrsc->irq, gh_msgq_tx_irq_handler, 0, "gh_msgq_tx",
162 msgq);
163 if (ret)
164 goto err_chans;
165 }
166
167 if (msgq->rx_ghrsc) {
168 ret = request_threaded_irq(msgq->rx_ghrsc->irq, NULL, gh_msgq_rx_irq_handler,
169 IRQF_ONESHOT, "gh_msgq_rx", msgq);
170 if (ret)
171 goto err_tx_irq;
172 }
173
174 tasklet_setup(&msgq->txdone_tasklet, gh_msgq_txdone_tasklet);
175
176 ret = mbox_controller_register(&msgq->mbox);
177 if (ret)
178 goto err_rx_irq;
179
> 180 ret = mbox_bind_client(gh_msgq_chan(msgq), cl);
181 if (ret)
182 goto err_mbox;
183
184 return 0;
185 err_mbox:
186 mbox_controller_unregister(&msgq->mbox);
187 err_rx_irq:
188 if (msgq->rx_ghrsc)
189 free_irq(msgq->rx_ghrsc->irq, msgq);
190 err_tx_irq:
191 if (msgq->tx_ghrsc)
192 free_irq(msgq->tx_ghrsc->irq, msgq);
193 err_chans:
194 kfree(msgq->mbox.chans);
195 return ret;
196 }
197 EXPORT_SYMBOL_GPL(gh_msgq_init);
198
On 14/02/2023 21:23, Elliot Berman wrote: > Gunyah message queues are a unidirectional inter-VM pipe for messages up > to 1024 bytes. This driver supports pairing a receiver message queue and > a transmitter message queue to expose a single mailbox channel. > > Signed-off-by: Elliot Berman <quic_eberman@quicinc.com> > --- > Documentation/virt/gunyah/message-queue.rst | 8 + > drivers/mailbox/Makefile | 2 + > drivers/mailbox/gunyah-msgq.c | 214 ++++++++++++++++++++ > include/linux/gunyah.h | 56 +++++ > 4 files changed, 280 insertions(+) > create mode 100644 drivers/mailbox/gunyah-msgq.c > > diff --git a/Documentation/virt/gunyah/message-queue.rst b/Documentation/virt/gunyah/message-queue.rst > index 0667b3eb1ff9..082085e981e0 100644 > --- a/Documentation/virt/gunyah/message-queue.rst > +++ b/Documentation/virt/gunyah/message-queue.rst > @@ -59,3 +59,11 @@ vIRQ: two TX message queues will have two vIRQs (and two capability IDs). > | | | | | | > | | | | | | > +---------------+ +-----------------+ +---------------+ > + > +Gunyah message queues are exposed as mailboxes. To create the mailbox, create > +a mbox_client and call `gh_msgq_init`. On receipt of the RX_READY interrupt, > +all messages in the RX message queue are read and pushed via the `rx_callback` > +of the registered mbox_client. > + > +.. kernel-doc:: drivers/mailbox/gunyah-msgq.c > + :identifiers: gh_msgq_init > diff --git a/drivers/mailbox/Makefile b/drivers/mailbox/Makefile > index fc9376117111..5f929bb55e9a 100644 > --- a/drivers/mailbox/Makefile > +++ b/drivers/mailbox/Makefile > @@ -55,6 +55,8 @@ obj-$(CONFIG_MTK_CMDQ_MBOX) += mtk-cmdq-mailbox.o > > obj-$(CONFIG_ZYNQMP_IPI_MBOX) += zynqmp-ipi-mailbox.o > > +obj-$(CONFIG_GUNYAH) += gunyah-msgq.o Why are we reusing CONFIG_GUNYAH Kconfig symbol for mailbox, why not CONFIG_GUNYAH_MBOX? > + > obj-$(CONFIG_SUN6I_MSGBOX) += sun6i-msgbox.o > > obj-$(CONFIG_SPRD_MBOX) += sprd-mailbox.o > diff --git a/drivers/mailbox/gunyah-msgq.c b/drivers/mailbox/gunyah-msgq.c > new file mode 100644 > index 000000000000..03ffaa30ce9b > --- /dev/null > +++ b/drivers/mailbox/gunyah-msgq.c > @@ -0,0 +1,214 @@ > +// SPDX-License-Identifier: GPL-2.0-only > +/* > + * Copyright (c) 2022-2023 Qualcomm Innovation Center, Inc. All rights reserved. > + */ > + > +#include <linux/mailbox_controller.h> > +#include <linux/module.h> > +#include <linux/interrupt.h> > +#include <linux/gunyah.h> > +#include <linux/printk.h> > +#include <linux/init.h> > +#include <linux/slab.h> > +#include <linux/wait.h> ... > +/* Fired when message queue transitions from "full" to "space available" to send messages */ > +static irqreturn_t gh_msgq_tx_irq_handler(int irq, void *data) > +{ > + struct gh_msgq *msgq = data; > + > + mbox_chan_txdone(gh_msgq_chan(msgq), 0); > + > + return IRQ_HANDLED; > +} > + > +/* Fired after sending message and hypercall told us there was more space available. */ > +static void gh_msgq_txdone_tasklet(struct tasklet_struct *tasklet) Tasklets have been long deprecated, consider using workqueues in this particular case. > +{ > + struct gh_msgq *msgq = container_of(tasklet, struct gh_msgq, txdone_tasklet); > + > + mbox_chan_txdone(gh_msgq_chan(msgq), msgq->last_ret); > +} > + > +static int gh_msgq_send_data(struct mbox_chan *chan, void *data) > +{ .. > + tasklet_schedule(&msgq->txdone_tasklet); > + > + return 0; > +} > + > +static struct mbox_chan_ops gh_msgq_ops = { > + .send_data = gh_msgq_send_data, > +}; > + > +/** > + * gh_msgq_init() - Initialize a Gunyah message queue with an mbox_client > + * @parent: optional, device parent used for the mailbox controller > + * @msgq: Pointer to the gh_msgq to initialize > + * @cl: A mailbox client to bind to the mailbox channel that the message queue creates > + * @tx_ghrsc: optional, the transmission side of the message queue > + * @rx_ghrsc: optional, the receiving side of the message queue > + * > + * At least one of tx_ghrsc and rx_ghrsc should be not NULL. Most message queue use cases come with > + * a pair of message queues to facilitate bidirectional communication. When tx_ghrsc is set, > + * the client can send messages with mbox_send_message(gh_msgq_chan(msgq), msg). When rx_ghrsc > + * is set, the mbox_client should register an .rx_callback() and the message queue driver will > + * push all available messages upon receiving the RX ready interrupt. The messages should be > + * consumed or copied by the client right away as the gh_msgq_rx_data will be replaced/destroyed > + * after the callback. > + * > + * Returns - 0 on success, negative otherwise > + */ > +int gh_msgq_init(struct device *parent, struct gh_msgq *msgq, struct mbox_client *cl, > + struct gunyah_resource *tx_ghrsc, struct gunyah_resource *rx_ghrsc) > +{ > + int ret; > + > + /* Must have at least a tx_ghrsc or rx_ghrsc and that they are the right device types */ > + if ((!tx_ghrsc && !rx_ghrsc) || > + (tx_ghrsc && tx_ghrsc->type != GUNYAH_RESOURCE_TYPE_MSGQ_TX) || > + (rx_ghrsc && rx_ghrsc->type != GUNYAH_RESOURCE_TYPE_MSGQ_RX)) > + return -EINVAL; > + > + if (gh_api_version() != GUNYAH_API_V1) { > + pr_err("Unrecognized gunyah version: %u. Currently supported: %d\n", dev_err(parent would make this more useful > + gh_api_version(), GUNYAH_API_V1); > + return -EOPNOTSUPP; > + } > + > + if (!gh_api_has_feature(GH_API_FEATURE_MSGQUEUE)) > + return -EOPNOTSUPP; > + > + msgq->tx_ghrsc = tx_ghrsc; > + msgq->rx_ghrsc = rx_ghrsc; > + > + msgq->mbox.dev = parent; > + msgq->mbox.ops = &gh_msgq_ops; > + msgq->mbox.num_chans = 1; > + msgq->mbox.txdone_irq = true; > + msgq->mbox.chans = kcalloc(msgq->mbox.num_chans, sizeof(*msgq->mbox.chans), GFP_KERNEL); > + if (!msgq->mbox.chans) > + return -ENOMEM; > + > + if (msgq->tx_ghrsc) { > + ret = request_irq(msgq->tx_ghrsc->irq, gh_msgq_tx_irq_handler, 0, "gh_msgq_tx", > + msgq); > + if (ret) > + goto err_chans; > + } > + > + if (msgq->rx_ghrsc) { > + ret = request_threaded_irq(msgq->rx_ghrsc->irq, NULL, gh_msgq_rx_irq_handler, > + IRQF_ONESHOT, "gh_msgq_rx", msgq); > + if (ret) > + goto err_tx_irq; > + } > + > + tasklet_setup(&msgq->txdone_tasklet, gh_msgq_txdone_tasklet); > + > + ret = mbox_controller_register(&msgq->mbox); > + if (ret) > + goto err_rx_irq; > + > + ret = mbox_bind_client(gh_msgq_chan(msgq), cl); > + if (ret) > + goto err_mbox; > + > + return 0; > +err_mbox: > + mbox_controller_unregister(&msgq->mbox); > +err_rx_irq: > + if (msgq->rx_ghrsc) > + free_irq(msgq->rx_ghrsc->irq, msgq); > +err_tx_irq: > + if (msgq->tx_ghrsc) > + free_irq(msgq->tx_ghrsc->irq, msgq); > +err_chans: > + kfree(msgq->mbox.chans); > + return ret; > +} > +EXPORT_SYMBOL_GPL(gh_msgq_init); > + > +void gh_msgq_remove(struct gh_msgq *msgq) > +{ > + mbox_controller_unregister(&msgq->mbox); > + > + if (msgq->rx_ghrsc) > + free_irq(msgq->rx_ghrsc->irq, msgq); > + > + if (msgq->tx_ghrsc) > + free_irq(msgq->tx_ghrsc->irq, msgq); > + > + kfree(msgq->mbox.chans); > +} > +EXPORT_SYMBOL_GPL(gh_msgq_remove); > + > +MODULE_LICENSE("GPL"); > +MODULE_DESCRIPTION("Gunyah Message Queue Driver");
On 2/20/2023 5:59 AM, Srinivas Kandagatla wrote: > > > On 14/02/2023 21:23, Elliot Berman wrote: >> Gunyah message queues are a unidirectional inter-VM pipe for messages up >> to 1024 bytes. This driver supports pairing a receiver message queue and >> a transmitter message queue to expose a single mailbox channel. >> >> Signed-off-by: Elliot Berman <quic_eberman@quicinc.com> >> --- >> Documentation/virt/gunyah/message-queue.rst | 8 + >> drivers/mailbox/Makefile | 2 + >> drivers/mailbox/gunyah-msgq.c | 214 ++++++++++++++++++++ >> include/linux/gunyah.h | 56 +++++ >> 4 files changed, 280 insertions(+) >> create mode 100644 drivers/mailbox/gunyah-msgq.c >> >> diff --git a/Documentation/virt/gunyah/message-queue.rst >> b/Documentation/virt/gunyah/message-queue.rst >> index 0667b3eb1ff9..082085e981e0 100644 >> --- a/Documentation/virt/gunyah/message-queue.rst >> +++ b/Documentation/virt/gunyah/message-queue.rst >> @@ -59,3 +59,11 @@ vIRQ: two TX message queues will have two vIRQs >> (and two capability IDs). >> | | | | >> | | >> | | | | >> | | >> +---------------+ +-----------------+ >> +---------------+ >> + >> +Gunyah message queues are exposed as mailboxes. To create the >> mailbox, create >> +a mbox_client and call `gh_msgq_init`. On receipt of the RX_READY >> interrupt, >> +all messages in the RX message queue are read and pushed via the >> `rx_callback` >> +of the registered mbox_client. >> + >> +.. kernel-doc:: drivers/mailbox/gunyah-msgq.c >> + :identifiers: gh_msgq_init >> diff --git a/drivers/mailbox/Makefile b/drivers/mailbox/Makefile >> index fc9376117111..5f929bb55e9a 100644 >> --- a/drivers/mailbox/Makefile >> +++ b/drivers/mailbox/Makefile >> @@ -55,6 +55,8 @@ obj-$(CONFIG_MTK_CMDQ_MBOX) += mtk-cmdq-mailbox.o >> obj-$(CONFIG_ZYNQMP_IPI_MBOX) += zynqmp-ipi-mailbox.o >> +obj-$(CONFIG_GUNYAH) += gunyah-msgq.o > > Why are we reusing CONFIG_GUNYAH Kconfig symbol for mailbox, why not > CONFIG_GUNYAH_MBOX? > There was some previous discussion about this: https://lore.kernel.org/all/2a7bb5f2-1286-b661-659a-a5037150eae8@quicinc.com/ >> + >> obj-$(CONFIG_SUN6I_MSGBOX) += sun6i-msgbox.o >> obj-$(CONFIG_SPRD_MBOX) += sprd-mailbox.o >> diff --git a/drivers/mailbox/gunyah-msgq.c >> b/drivers/mailbox/gunyah-msgq.c >> new file mode 100644 >> index 000000000000..03ffaa30ce9b >> --- /dev/null >> +++ b/drivers/mailbox/gunyah-msgq.c >> @@ -0,0 +1,214 @@ >> +// SPDX-License-Identifier: GPL-2.0-only >> +/* >> + * Copyright (c) 2022-2023 Qualcomm Innovation Center, Inc. All >> rights reserved. >> + */ >> + >> +#include <linux/mailbox_controller.h> >> +#include <linux/module.h> >> +#include <linux/interrupt.h> >> +#include <linux/gunyah.h> >> +#include <linux/printk.h> >> +#include <linux/init.h> >> +#include <linux/slab.h> >> +#include <linux/wait.h> > > ... > >> +/* Fired when message queue transitions from "full" to "space >> available" to send messages */ >> +static irqreturn_t gh_msgq_tx_irq_handler(int irq, void *data) >> +{ >> + struct gh_msgq *msgq = data; >> + >> + mbox_chan_txdone(gh_msgq_chan(msgq), 0); >> + >> + return IRQ_HANDLED; >> +} >> + >> +/* Fired after sending message and hypercall told us there was more >> space available. */ >> +static void gh_msgq_txdone_tasklet(struct tasklet_struct *tasklet) > > Tasklets have been long deprecated, consider using workqueues in this > particular case. > Workqueues have higher latency and tasklets came as recommendation from Jassi. drivers/mailbox/imx-mailbox.c uses tasklets in the same way. I did some quick unscientific measurements of ~1000x samples. The median latency for resource manager went from 25.5 us (tasklet) to 26 us (workqueue) (2% slower). The mean went from 28.7 us to 32.5 us (13% slower). Obviously, the outliers for workqueues were much more extreme. > >> +{ >> + struct gh_msgq *msgq = container_of(tasklet, struct gh_msgq, >> txdone_tasklet); >> + >> + mbox_chan_txdone(gh_msgq_chan(msgq), msgq->last_ret); >> +} >> + >> +static int gh_msgq_send_data(struct mbox_chan *chan, void *data) >> +{ > .. > >> + tasklet_schedule(&msgq->txdone_tasklet); >> + >> + return 0; >> +} >> + >> +static struct mbox_chan_ops gh_msgq_ops = { >> + .send_data = gh_msgq_send_data, >> +}; >> + >> +/** >> + * gh_msgq_init() - Initialize a Gunyah message queue with an >> mbox_client >> + * @parent: optional, device parent used for the mailbox controller >> + * @msgq: Pointer to the gh_msgq to initialize >> + * @cl: A mailbox client to bind to the mailbox channel that the >> message queue creates >> + * @tx_ghrsc: optional, the transmission side of the message queue >> + * @rx_ghrsc: optional, the receiving side of the message queue >> + * >> + * At least one of tx_ghrsc and rx_ghrsc should be not NULL. Most >> message queue use cases come with >> + * a pair of message queues to facilitate bidirectional >> communication. When tx_ghrsc is set, >> + * the client can send messages with >> mbox_send_message(gh_msgq_chan(msgq), msg). When rx_ghrsc >> + * is set, the mbox_client should register an .rx_callback() and the >> message queue driver will >> + * push all available messages upon receiving the RX ready interrupt. >> The messages should be >> + * consumed or copied by the client right away as the gh_msgq_rx_data >> will be replaced/destroyed >> + * after the callback. >> + * >> + * Returns - 0 on success, negative otherwise >> + */ >> +int gh_msgq_init(struct device *parent, struct gh_msgq *msgq, struct >> mbox_client *cl, >> + struct gunyah_resource *tx_ghrsc, struct gunyah_resource >> *rx_ghrsc) >> +{ >> + int ret; >> + >> + /* Must have at least a tx_ghrsc or rx_ghrsc and that they are >> the right device types */ >> + if ((!tx_ghrsc && !rx_ghrsc) || >> + (tx_ghrsc && tx_ghrsc->type != GUNYAH_RESOURCE_TYPE_MSGQ_TX) || >> + (rx_ghrsc && rx_ghrsc->type != GUNYAH_RESOURCE_TYPE_MSGQ_RX)) >> + return -EINVAL; >> + >> + if (gh_api_version() != GUNYAH_API_V1) { >> + pr_err("Unrecognized gunyah version: %u. Currently supported: >> %d\n", > dev_err(parent > > would make this more useful > Done. - Elliot
On 23/02/2023 00:15, Elliot Berman wrote: > > > On 2/20/2023 5:59 AM, Srinivas Kandagatla wrote: >> >> >> On 14/02/2023 21:23, Elliot Berman wrote: >>> Gunyah message queues are a unidirectional inter-VM pipe for messages up >>> to 1024 bytes. This driver supports pairing a receiver message queue and >>> a transmitter message queue to expose a single mailbox channel. >>> >>> Signed-off-by: Elliot Berman <quic_eberman@quicinc.com> >>> --- >>> Documentation/virt/gunyah/message-queue.rst | 8 + >>> drivers/mailbox/Makefile | 2 + >>> drivers/mailbox/gunyah-msgq.c | 214 ++++++++++++++++++++ >>> include/linux/gunyah.h | 56 +++++ >>> 4 files changed, 280 insertions(+) >>> create mode 100644 drivers/mailbox/gunyah-msgq.c >>> >>> diff --git a/Documentation/virt/gunyah/message-queue.rst >>> b/Documentation/virt/gunyah/message-queue.rst >>> index 0667b3eb1ff9..082085e981e0 100644 >>> --- a/Documentation/virt/gunyah/message-queue.rst >>> +++ b/Documentation/virt/gunyah/message-queue.rst >>> @@ -59,3 +59,11 @@ vIRQ: two TX message queues will have two vIRQs >>> (and two capability IDs). >>> | | | | | | >>> | | | | | | >>> +---------------+ +-----------------+ +---------------+ >>> + >>> +Gunyah message queues are exposed as mailboxes. To create the >>> mailbox, create >>> +a mbox_client and call `gh_msgq_init`. On receipt of the RX_READY >>> interrupt, >>> +all messages in the RX message queue are read and pushed via the >>> `rx_callback` >>> +of the registered mbox_client. >>> + >>> +.. kernel-doc:: drivers/mailbox/gunyah-msgq.c >>> + :identifiers: gh_msgq_init >>> diff --git a/drivers/mailbox/Makefile b/drivers/mailbox/Makefile >>> index fc9376117111..5f929bb55e9a 100644 >>> --- a/drivers/mailbox/Makefile >>> +++ b/drivers/mailbox/Makefile >>> @@ -55,6 +55,8 @@ obj-$(CONFIG_MTK_CMDQ_MBOX) += mtk-cmdq-mailbox.o >>> obj-$(CONFIG_ZYNQMP_IPI_MBOX) += zynqmp-ipi-mailbox.o >>> +obj-$(CONFIG_GUNYAH) += gunyah-msgq.o >> >> Why are we reusing CONFIG_GUNYAH Kconfig symbol for mailbox, why not >> CONFIG_GUNYAH_MBOX? >> > > There was some previous discussion about this: > > https://lore.kernel.org/all/2a7bb5f2-1286-b661-659a-a5037150eae8@quicinc.com/ > >>> + >>> obj-$(CONFIG_SUN6I_MSGBOX) += sun6i-msgbox.o >>> obj-$(CONFIG_SPRD_MBOX) += sprd-mailbox.o >>> diff --git a/drivers/mailbox/gunyah-msgq.c >>> b/drivers/mailbox/gunyah-msgq.c >>> new file mode 100644 >>> index 000000000000..03ffaa30ce9b >>> --- /dev/null >>> +++ b/drivers/mailbox/gunyah-msgq.c >>> @@ -0,0 +1,214 @@ >>> +// SPDX-License-Identifier: GPL-2.0-only >>> +/* >>> + * Copyright (c) 2022-2023 Qualcomm Innovation Center, Inc. All >>> rights reserved. >>> + */ >>> + >>> +#include <linux/mailbox_controller.h> >>> +#include <linux/module.h> >>> +#include <linux/interrupt.h> >>> +#include <linux/gunyah.h> >>> +#include <linux/printk.h> >>> +#include <linux/init.h> >>> +#include <linux/slab.h> >>> +#include <linux/wait.h> >> >> ... >> >>> +/* Fired when message queue transitions from "full" to "space >>> available" to send messages */ >>> +static irqreturn_t gh_msgq_tx_irq_handler(int irq, void *data) >>> +{ >>> + struct gh_msgq *msgq = data; >>> + >>> + mbox_chan_txdone(gh_msgq_chan(msgq), 0); >>> + >>> + return IRQ_HANDLED; >>> +} >>> + >>> +/* Fired after sending message and hypercall told us there was more >>> space available. */ >>> +static void gh_msgq_txdone_tasklet(struct tasklet_struct *tasklet) >> >> Tasklets have been long deprecated, consider using workqueues in this >> particular case. >> > > Workqueues have higher latency and tasklets came as recommendation from > Jassi. drivers/mailbox/imx-mailbox.c uses tasklets in the same way. > > I did some quick unscientific measurements of ~1000x samples. The median > latency for resource manager went from 25.5 us (tasklet) to 26 us > (workqueue) (2% slower). The mean went from 28.7 us to 32.5 us (13% > slower). Obviously, the outliers for workqueues were much more extreme. TBH, this is expected because we are only testing resource manager, Note the advantage that you will see shifting from tasket to workqueues is on overall system latencies and some drivers performance that need to react to events. please take some time to read this nice article about this https://lwn.net/Articles/830964/ --srini > >> >>> +{ >>> + struct gh_msgq *msgq = container_of(tasklet, struct gh_msgq, >>> txdone_tasklet); >>> + >>> + mbox_chan_txdone(gh_msgq_chan(msgq), msgq->last_ret); >>> +} >>> + >>> +static int gh_msgq_send_data(struct mbox_chan *chan, void *data) >>> +{ >> .. >> >>> + tasklet_schedule(&msgq->txdone_tasklet); >>> + >>> + return 0; >>> +} >>> + >>> +static struct mbox_chan_ops gh_msgq_ops = { >>> + .send_data = gh_msgq_send_data, >>> +}; >>> + >>> +/** >>> + * gh_msgq_init() - Initialize a Gunyah message queue with an >>> mbox_client >>> + * @parent: optional, device parent used for the mailbox controller >>> + * @msgq: Pointer to the gh_msgq to initialize >>> + * @cl: A mailbox client to bind to the mailbox channel that the >>> message queue creates >>> + * @tx_ghrsc: optional, the transmission side of the message queue >>> + * @rx_ghrsc: optional, the receiving side of the message queue >>> + * >>> + * At least one of tx_ghrsc and rx_ghrsc should be not NULL. Most >>> message queue use cases come with >>> + * a pair of message queues to facilitate bidirectional >>> communication. When tx_ghrsc is set, >>> + * the client can send messages with >>> mbox_send_message(gh_msgq_chan(msgq), msg). When rx_ghrsc >>> + * is set, the mbox_client should register an .rx_callback() and the >>> message queue driver will >>> + * push all available messages upon receiving the RX ready >>> interrupt. The messages should be >>> + * consumed or copied by the client right away as the >>> gh_msgq_rx_data will be replaced/destroyed >>> + * after the callback. >>> + * >>> + * Returns - 0 on success, negative otherwise >>> + */ >>> +int gh_msgq_init(struct device *parent, struct gh_msgq *msgq, struct >>> mbox_client *cl, >>> + struct gunyah_resource *tx_ghrsc, struct >>> gunyah_resource *rx_ghrsc) >>> +{ >>> + int ret; >>> + >>> + /* Must have at least a tx_ghrsc or rx_ghrsc and that they are >>> the right device types */ >>> + if ((!tx_ghrsc && !rx_ghrsc) || >>> + (tx_ghrsc && tx_ghrsc->type != GUNYAH_RESOURCE_TYPE_MSGQ_TX) || >>> + (rx_ghrsc && rx_ghrsc->type != GUNYAH_RESOURCE_TYPE_MSGQ_RX)) >>> + return -EINVAL; >>> + >>> + if (gh_api_version() != GUNYAH_API_V1) { >>> + pr_err("Unrecognized gunyah version: %u. Currently >>> supported: %d\n", >> dev_err(parent >> >> would make this more useful >> > > Done. > > - Elliot
On 2/14/23 3:23 PM, Elliot Berman wrote: > Gunyah message queues are a unidirectional inter-VM pipe for messages up > to 1024 bytes. This driver supports pairing a receiver message queue and > a transmitter message queue to expose a single mailbox channel. > > Signed-off-by: Elliot Berman <quic_eberman@quicinc.com> I have a general comment for "include/linux/gunyah.h". You sometimes use "gunyah" in exported names (for example, enum gunyah_resource_type, or struct gunyah_resource). In many cases, though, you use "gh_ or "GH_" (such as in struct gh_msgq, or GH_DBL_NONBLOCK). Is there a reason that you don't pick one and use it everywhere? I think it would be best--certainly for exported symbols like these--to use a single symbol prefix for all cases. Sometimes there might be a reason to distinguish two names (maybe "gunyah_" symbols are truly public, while "gh_" symbols are helpers meant generally to be private). But I don't think that's the case here. It seems that "gh" is your most frequent prefix, so that might be easier to implement. But "gunyah" is more expressive and is only 4 characters wider. -Alex > --- > Documentation/virt/gunyah/message-queue.rst | 8 + > drivers/mailbox/Makefile | 2 + > drivers/mailbox/gunyah-msgq.c | 214 ++++++++++++++++++++ > include/linux/gunyah.h | 56 +++++ > 4 files changed, 280 insertions(+) > create mode 100644 drivers/mailbox/gunyah-msgq.c > > diff --git a/Documentation/virt/gunyah/message-queue.rst b/Documentation/virt/gunyah/message-queue.rst > index 0667b3eb1ff9..082085e981e0 100644 > --- a/Documentation/virt/gunyah/message-queue.rst > +++ b/Documentation/virt/gunyah/message-queue.rst > @@ -59,3 +59,11 @@ vIRQ: two TX message queues will have two vIRQs (and two capability IDs). > | | | | | | > | | | | | | > +---------------+ +-----------------+ +---------------+ > + > +Gunyah message queues are exposed as mailboxes. To create the mailbox, create > +a mbox_client and call `gh_msgq_init`. On receipt of the RX_READY interrupt, > +all messages in the RX message queue are read and pushed via the `rx_callback` > +of the registered mbox_client. > + > +.. kernel-doc:: drivers/mailbox/gunyah-msgq.c > + :identifiers: gh_msgq_init > diff --git a/drivers/mailbox/Makefile b/drivers/mailbox/Makefile > index fc9376117111..5f929bb55e9a 100644 > --- a/drivers/mailbox/Makefile > +++ b/drivers/mailbox/Makefile > @@ -55,6 +55,8 @@ obj-$(CONFIG_MTK_CMDQ_MBOX) += mtk-cmdq-mailbox.o > > obj-$(CONFIG_ZYNQMP_IPI_MBOX) += zynqmp-ipi-mailbox.o > > +obj-$(CONFIG_GUNYAH) += gunyah-msgq.o > + > obj-$(CONFIG_SUN6I_MSGBOX) += sun6i-msgbox.o > > obj-$(CONFIG_SPRD_MBOX) += sprd-mailbox.o > diff --git a/drivers/mailbox/gunyah-msgq.c b/drivers/mailbox/gunyah-msgq.c > new file mode 100644 > index 000000000000..03ffaa30ce9b > --- /dev/null > +++ b/drivers/mailbox/gunyah-msgq.c > @@ -0,0 +1,214 @@ > +// SPDX-License-Identifier: GPL-2.0-only > +/* > + * Copyright (c) 2022-2023 Qualcomm Innovation Center, Inc. All rights reserved. > + */ > + > +#include <linux/mailbox_controller.h> > +#include <linux/module.h> > +#include <linux/interrupt.h> > +#include <linux/gunyah.h> > +#include <linux/printk.h> > +#include <linux/init.h> > +#include <linux/slab.h> > +#include <linux/wait.h> > + > +#define mbox_chan_to_msgq(chan) (container_of(chan->mbox, struct gh_msgq, mbox)) > + > +static irqreturn_t gh_msgq_rx_irq_handler(int irq, void *data) > +{ > + struct gh_msgq *msgq = data; > + struct gh_msgq_rx_data rx_data; > + enum gh_error err; > + bool ready = true; > + > + while (ready) { > + err = gh_hypercall_msgq_recv(msgq->rx_ghrsc->capid, > + (uintptr_t)&rx_data.data, sizeof(rx_data.data), > + &rx_data.length, &ready); > + if (err != GH_ERROR_OK) { > + if (err != GH_ERROR_MSGQUEUE_EMPTY) > + pr_warn("Failed to receive data from msgq for %s: %d\n", > + msgq->mbox.dev ? dev_name(msgq->mbox.dev) : "", err); > + break; > + } > + mbox_chan_received_data(gh_msgq_chan(msgq), &rx_data); > + } > + > + return IRQ_HANDLED; > +} > + > +/* Fired when message queue transitions from "full" to "space available" to send messages */ > +static irqreturn_t gh_msgq_tx_irq_handler(int irq, void *data) > +{ > + struct gh_msgq *msgq = data; > + > + mbox_chan_txdone(gh_msgq_chan(msgq), 0); > + > + return IRQ_HANDLED; > +} > + > +/* Fired after sending message and hypercall told us there was more space available. */ > +static void gh_msgq_txdone_tasklet(struct tasklet_struct *tasklet) > +{ > + struct gh_msgq *msgq = container_of(tasklet, struct gh_msgq, txdone_tasklet); > + > + mbox_chan_txdone(gh_msgq_chan(msgq), msgq->last_ret); > +} > + > +static int gh_msgq_send_data(struct mbox_chan *chan, void *data) > +{ > + struct gh_msgq *msgq = mbox_chan_to_msgq(chan); > + struct gh_msgq_tx_data *msgq_data = data; > + u64 tx_flags = 0; > + enum gh_error gh_error; > + bool ready; > + > + if (msgq_data->push) > + tx_flags |= GH_HYPERCALL_MSGQ_TX_FLAGS_PUSH; > + > + gh_error = gh_hypercall_msgq_send(msgq->tx_ghrsc->capid, msgq_data->length, > + (uintptr_t)msgq_data->data, tx_flags, &ready); > + > + /** > + * unlikely because Linux tracks state of msgq and should not try to > + * send message when msgq is full. > + */ > + if (unlikely(gh_error == GH_ERROR_MSGQUEUE_FULL)) > + return -EAGAIN; > + > + /** > + * Propagate all other errors to client. If we return error to mailbox > + * framework, then no other messages can be sent and nobody will know > + * to retry this message. > + */ > + msgq->last_ret = gh_remap_error(gh_error); > + > + /** > + * This message was successfully sent, but message queue isn't ready to > + * receive more messages because it's now full. Mailbox framework > + * requires that we only report that message was transmitted when > + * we're ready to transmit another message. We'll get that in the form > + * of tx IRQ once the other side starts to drain the msgq. > + */ > + if (gh_error == GH_ERROR_OK && !ready) > + return 0; > + > + /** > + * We can send more messages. Mailbox framework requires that tx done > + * happens asynchronously to sending the message. Gunyah message queues > + * tell us right away on the hypercall return whether we can send more > + * messages. To work around this, defer the txdone to a tasklet. > + */ > + tasklet_schedule(&msgq->txdone_tasklet); > + > + return 0; > +} > + > +static struct mbox_chan_ops gh_msgq_ops = { > + .send_data = gh_msgq_send_data, > +}; > + > +/** > + * gh_msgq_init() - Initialize a Gunyah message queue with an mbox_client > + * @parent: optional, device parent used for the mailbox controller > + * @msgq: Pointer to the gh_msgq to initialize > + * @cl: A mailbox client to bind to the mailbox channel that the message queue creates > + * @tx_ghrsc: optional, the transmission side of the message queue > + * @rx_ghrsc: optional, the receiving side of the message queue > + * > + * At least one of tx_ghrsc and rx_ghrsc should be not NULL. Most message queue use cases come with > + * a pair of message queues to facilitate bidirectional communication. When tx_ghrsc is set, > + * the client can send messages with mbox_send_message(gh_msgq_chan(msgq), msg). When rx_ghrsc > + * is set, the mbox_client should register an .rx_callback() and the message queue driver will > + * push all available messages upon receiving the RX ready interrupt. The messages should be > + * consumed or copied by the client right away as the gh_msgq_rx_data will be replaced/destroyed > + * after the callback. > + * > + * Returns - 0 on success, negative otherwise > + */ > +int gh_msgq_init(struct device *parent, struct gh_msgq *msgq, struct mbox_client *cl, > + struct gunyah_resource *tx_ghrsc, struct gunyah_resource *rx_ghrsc) > +{ > + int ret; > + > + /* Must have at least a tx_ghrsc or rx_ghrsc and that they are the right device types */ > + if ((!tx_ghrsc && !rx_ghrsc) || > + (tx_ghrsc && tx_ghrsc->type != GUNYAH_RESOURCE_TYPE_MSGQ_TX) || > + (rx_ghrsc && rx_ghrsc->type != GUNYAH_RESOURCE_TYPE_MSGQ_RX)) > + return -EINVAL; > + > + if (gh_api_version() != GUNYAH_API_V1) { > + pr_err("Unrecognized gunyah version: %u. Currently supported: %d\n", > + gh_api_version(), GUNYAH_API_V1); > + return -EOPNOTSUPP; > + } > + > + if (!gh_api_has_feature(GH_API_FEATURE_MSGQUEUE)) > + return -EOPNOTSUPP; > + > + msgq->tx_ghrsc = tx_ghrsc; > + msgq->rx_ghrsc = rx_ghrsc; > + > + msgq->mbox.dev = parent; > + msgq->mbox.ops = &gh_msgq_ops; > + msgq->mbox.num_chans = 1; > + msgq->mbox.txdone_irq = true; > + msgq->mbox.chans = kcalloc(msgq->mbox.num_chans, sizeof(*msgq->mbox.chans), GFP_KERNEL); > + if (!msgq->mbox.chans) > + return -ENOMEM; > + > + if (msgq->tx_ghrsc) { > + ret = request_irq(msgq->tx_ghrsc->irq, gh_msgq_tx_irq_handler, 0, "gh_msgq_tx", > + msgq); > + if (ret) > + goto err_chans; > + } > + > + if (msgq->rx_ghrsc) { > + ret = request_threaded_irq(msgq->rx_ghrsc->irq, NULL, gh_msgq_rx_irq_handler, > + IRQF_ONESHOT, "gh_msgq_rx", msgq); > + if (ret) > + goto err_tx_irq; > + } > + > + tasklet_setup(&msgq->txdone_tasklet, gh_msgq_txdone_tasklet); > + > + ret = mbox_controller_register(&msgq->mbox); > + if (ret) > + goto err_rx_irq; > + > + ret = mbox_bind_client(gh_msgq_chan(msgq), cl); > + if (ret) > + goto err_mbox; > + > + return 0; > +err_mbox: > + mbox_controller_unregister(&msgq->mbox); > +err_rx_irq: > + if (msgq->rx_ghrsc) > + free_irq(msgq->rx_ghrsc->irq, msgq); > +err_tx_irq: > + if (msgq->tx_ghrsc) > + free_irq(msgq->tx_ghrsc->irq, msgq); > +err_chans: > + kfree(msgq->mbox.chans); > + return ret; > +} > +EXPORT_SYMBOL_GPL(gh_msgq_init); > + > +void gh_msgq_remove(struct gh_msgq *msgq) > +{ > + mbox_controller_unregister(&msgq->mbox); > + > + if (msgq->rx_ghrsc) > + free_irq(msgq->rx_ghrsc->irq, msgq); > + > + if (msgq->tx_ghrsc) > + free_irq(msgq->tx_ghrsc->irq, msgq); > + > + kfree(msgq->mbox.chans); > +} > +EXPORT_SYMBOL_GPL(gh_msgq_remove); > + > +MODULE_LICENSE("GPL"); > +MODULE_DESCRIPTION("Gunyah Message Queue Driver"); > diff --git a/include/linux/gunyah.h b/include/linux/gunyah.h > index cb6df4eec5c2..2e13669c6363 100644 > --- a/include/linux/gunyah.h > +++ b/include/linux/gunyah.h > @@ -8,11 +8,67 @@ > > #include <linux/bitfield.h> > #include <linux/errno.h> > +#include <linux/interrupt.h> > #include <linux/limits.h> > +#include <linux/mailbox_controller.h> > +#include <linux/mailbox_client.h> > #include <linux/types.h> > > +/* Follows resource manager's resource types for VM_GET_HYP_RESOURCES */ > +enum gunyah_resource_type { > + GUNYAH_RESOURCE_TYPE_BELL_TX = 0, > + GUNYAH_RESOURCE_TYPE_BELL_RX = 1, > + GUNYAH_RESOURCE_TYPE_MSGQ_TX = 2, > + GUNYAH_RESOURCE_TYPE_MSGQ_RX = 3, > + GUNYAH_RESOURCE_TYPE_VCPU = 4, > +}; > + > +struct gunyah_resource { > + enum gunyah_resource_type type; > + u64 capid; > + int irq; > +}; > + > +/** > + * Gunyah Message Queues > + */ > + > +#define GH_MSGQ_MAX_MSG_SIZE 240 > + > +struct gh_msgq_tx_data { > + size_t length; > + bool push; > + char data[]; > +}; > + > +struct gh_msgq_rx_data { > + size_t length; > + char data[GH_MSGQ_MAX_MSG_SIZE]; > +}; > + > +struct gh_msgq { > + struct gunyah_resource *tx_ghrsc; > + struct gunyah_resource *rx_ghrsc; > + > + /* msgq private */ > + int last_ret; /* Linux error, not GH_STATUS_* */ > + struct mbox_controller mbox; > + struct tasklet_struct txdone_tasklet; > +}; > + > + > +int gh_msgq_init(struct device *parent, struct gh_msgq *msgq, struct mbox_client *cl, > + struct gunyah_resource *tx_ghrsc, struct gunyah_resource *rx_ghrsc); > +void gh_msgq_remove(struct gh_msgq *msgq); > + > +static inline struct mbox_chan *gh_msgq_chan(struct gh_msgq *msgq) > +{ > + return &msgq->mbox.chans[0]; > +} > + > /******************************************************************************/ > /* Common arch-independent definitions for Gunyah hypercalls */ > + > #define GH_CAPID_INVAL U64_MAX > #define GH_VMID_ROOT_VM 0xff >
On 2/14/23 3:23 PM, Elliot Berman wrote: > Gunyah message queues are a unidirectional inter-VM pipe for messages up > to 1024 bytes. This driver supports pairing a receiver message queue and > a transmitter message queue to expose a single mailbox channel. > > Signed-off-by: Elliot Berman <quic_eberman@quicinc.com> > --- > Documentation/virt/gunyah/message-queue.rst | 8 + > drivers/mailbox/Makefile | 2 + > drivers/mailbox/gunyah-msgq.c | 214 ++++++++++++++++++++ > include/linux/gunyah.h | 56 +++++ > 4 files changed, 280 insertions(+) > create mode 100644 drivers/mailbox/gunyah-msgq.c > > diff --git a/Documentation/virt/gunyah/message-queue.rst b/Documentation/virt/gunyah/message-queue.rst > index 0667b3eb1ff9..082085e981e0 100644 > --- a/Documentation/virt/gunyah/message-queue.rst > +++ b/Documentation/virt/gunyah/message-queue.rst > @@ -59,3 +59,11 @@ vIRQ: two TX message queues will have two vIRQs (and two capability IDs). > | | | | | | > | | | | | | > +---------------+ +-----------------+ +---------------+ > + > +Gunyah message queues are exposed as mailboxes. To create the mailbox, create > +a mbox_client and call `gh_msgq_init`. On receipt of the RX_READY interrupt, > +all messages in the RX message queue are read and pushed via the `rx_callback` > +of the registered mbox_client. > + > +.. kernel-doc:: drivers/mailbox/gunyah-msgq.c > + :identifiers: gh_msgq_init > diff --git a/drivers/mailbox/Makefile b/drivers/mailbox/Makefile > index fc9376117111..5f929bb55e9a 100644 > --- a/drivers/mailbox/Makefile > +++ b/drivers/mailbox/Makefile > @@ -55,6 +55,8 @@ obj-$(CONFIG_MTK_CMDQ_MBOX) += mtk-cmdq-mailbox.o > > obj-$(CONFIG_ZYNQMP_IPI_MBOX) += zynqmp-ipi-mailbox.o > > +obj-$(CONFIG_GUNYAH) += gunyah-msgq.o > + > obj-$(CONFIG_SUN6I_MSGBOX) += sun6i-msgbox.o > > obj-$(CONFIG_SPRD_MBOX) += sprd-mailbox.o > diff --git a/drivers/mailbox/gunyah-msgq.c b/drivers/mailbox/gunyah-msgq.c > new file mode 100644 > index 000000000000..03ffaa30ce9b > --- /dev/null > +++ b/drivers/mailbox/gunyah-msgq.c You use a dash in this source file name, but an underscore everywhere else. Unless there's a good reason to do this, please be consistent (use "gunyah_msgq.c"). > @@ -0,0 +1,214 @@ > +// SPDX-License-Identifier: GPL-2.0-only > +/* > + * Copyright (c) 2022-2023 Qualcomm Innovation Center, Inc. All rights reserved. > + */ > + > +#include <linux/mailbox_controller.h> > +#include <linux/module.h> > +#include <linux/interrupt.h> > +#include <linux/gunyah.h> > +#include <linux/printk.h> > +#include <linux/init.h> > +#include <linux/slab.h> > +#include <linux/wait.h> > + > +#define mbox_chan_to_msgq(chan) (container_of(chan->mbox, struct gh_msgq, mbox)) > + > +static irqreturn_t gh_msgq_rx_irq_handler(int irq, void *data) > +{ > + struct gh_msgq *msgq = data; > + struct gh_msgq_rx_data rx_data; > + enum gh_error err; > + bool ready = true; > + > + while (ready) { > + err = gh_hypercall_msgq_recv(msgq->rx_ghrsc->capid, > + (uintptr_t)&rx_data.data, sizeof(rx_data.data), > + &rx_data.length, &ready); > + if (err != GH_ERROR_OK) { > + if (err != GH_ERROR_MSGQUEUE_EMPTY) Srini mentioned something about this too. In many (all?) cases, there is a device pointer available, so you should use dev_*() functions rather than pr_*(). In this particular case, I'm not sure why/when the mbox.dev pointer would be null. Also, dev_*() handles the case of a null device pointer, and it reports the device name (just as you do here). > + pr_warn("Failed to receive data from msgq for %s: %d\n", > + msgq->mbox.dev ? dev_name(msgq->mbox.dev) : "", err); > + break; > + } > + mbox_chan_received_data(gh_msgq_chan(msgq), &rx_data); > + } > + > + return IRQ_HANDLED; > +} > + > +/* Fired when message queue transitions from "full" to "space available" to send messages */ > +static irqreturn_t gh_msgq_tx_irq_handler(int irq, void *data) > +{ > + struct gh_msgq *msgq = data; > + > + mbox_chan_txdone(gh_msgq_chan(msgq), 0); > + > + return IRQ_HANDLED; > +} > + > +/* Fired after sending message and hypercall told us there was more space available. */ > +static void gh_msgq_txdone_tasklet(struct tasklet_struct *tasklet) > +{ > + struct gh_msgq *msgq = container_of(tasklet, struct gh_msgq, txdone_tasklet); > + > + mbox_chan_txdone(gh_msgq_chan(msgq), msgq->last_ret); > +} > + > +static int gh_msgq_send_data(struct mbox_chan *chan, void *data) > +{ > + struct gh_msgq *msgq = mbox_chan_to_msgq(chan); > + struct gh_msgq_tx_data *msgq_data = data; > + u64 tx_flags = 0; > + enum gh_error gh_error; Above you named the variable "err". It helps readability if you use a very consistent naming convention for variables of a certain type when they are used a lot. > + bool ready; > + > + if (msgq_data->push) > + tx_flags |= GH_HYPERCALL_MSGQ_TX_FLAGS_PUSH; > + > + gh_error = gh_hypercall_msgq_send(msgq->tx_ghrsc->capid, msgq_data->length, > + (uintptr_t)msgq_data->data, tx_flags, &ready); > + > + /** > + * unlikely because Linux tracks state of msgq and should not try to > + * send message when msgq is full. > + */ > + if (unlikely(gh_error == GH_ERROR_MSGQUEUE_FULL)) > + return -EAGAIN; > + > + /** > + * Propagate all other errors to client. If we return error to mailbox > + * framework, then no other messages can be sent and nobody will know > + * to retry this message. > + */ > + msgq->last_ret = gh_remap_error(gh_error); > + > + /** > + * This message was successfully sent, but message queue isn't ready to > + * receive more messages because it's now full. Mailbox framework Maybe: s/receive/accept/ > + * requires that we only report that message was transmitted when > + * we're ready to transmit another message. We'll get that in the form > + * of tx IRQ once the other side starts to drain the msgq. > + */ > + if (gh_error == GH_ERROR_OK && !ready) > + return 0; > + > + /** > + * We can send more messages. Mailbox framework requires that tx done > + * happens asynchronously to sending the message. Gunyah message queues > + * tell us right away on the hypercall return whether we can send more > + * messages. To work around this, defer the txdone to a tasklet. > + */ > + tasklet_schedule(&msgq->txdone_tasklet); > + > + return 0; > +} > + > +static struct mbox_chan_ops gh_msgq_ops = { > + .send_data = gh_msgq_send_data, > +}; > + > +/** > + * gh_msgq_init() - Initialize a Gunyah message queue with an mbox_client > + * @parent: optional, device parent used for the mailbox controller > + * @msgq: Pointer to the gh_msgq to initialize > + * @cl: A mailbox client to bind to the mailbox channel that the message queue creates > + * @tx_ghrsc: optional, the transmission side of the message queue > + * @rx_ghrsc: optional, the receiving side of the message queue > + * > + * At least one of tx_ghrsc and rx_ghrsc should be not NULL. Most message queue use cases come with s/should be/must be/ > + * a pair of message queues to facilitate bidirectional communication. When tx_ghrsc is set, > + * the client can send messages with mbox_send_message(gh_msgq_chan(msgq), msg). When rx_ghrsc > + * is set, the mbox_client should register an .rx_callback() and the message queue driver will s/should register/must register/ A general comment on this code is that you sort of half define a Gunyah message queue API. You define an initialization function and an exit function, but you also expose the fact that you use the mailbox framework in implementation. This despite avoiding defining it as an mbox in the DTS file. It might be hard to avoid that I guess. But to me it would be nice if there were a more distinct Gunyah message queue API, which would provide a send_message() function, for example. And in that case, perhaps you would pass in the tx_done and/or rx_data callbacks to this function (since they're required). All that said, this is (currently?) only used by the resource manager, so making a beautiful API might not be that important. Do you envision this being used to communicate with other VMs in the future? > + * push all available messages upon receiving the RX ready interrupt. The messages should be Maybe: s/push/deliver/ > + * consumed or copied by the client right away as the gh_msgq_rx_data will be replaced/destroyed > + * after the callback. > + * > + * Returns - 0 on success, negative otherwise > + */ > +int gh_msgq_init(struct device *parent, struct gh_msgq *msgq, struct mbox_client *cl, > + struct gunyah_resource *tx_ghrsc, struct gunyah_resource *rx_ghrsc) > +{ > + int ret; > + > + /* Must have at least a tx_ghrsc or rx_ghrsc and that they are the right device types */ > + if ((!tx_ghrsc && !rx_ghrsc) || > + (tx_ghrsc && tx_ghrsc->type != GUNYAH_RESOURCE_TYPE_MSGQ_TX) || > + (rx_ghrsc && rx_ghrsc->type != GUNYAH_RESOURCE_TYPE_MSGQ_RX)) > + return -EINVAL; > + > + if (gh_api_version() != GUNYAH_API_V1) { > + pr_err("Unrecognized gunyah version: %u. Currently supported: %d\n", > + gh_api_version(), GUNYAH_API_V1); > + return -EOPNOTSUPP; > + } > + > + if (!gh_api_has_feature(GH_API_FEATURE_MSGQUEUE)) > + return -EOPNOTSUPP; Can Gunyah even function if it doesn't have the MSGQUEUE feature? Will there ever be a Gunyah implementation that does not support it? Perhaps this test could be done in gunyah_init() instead. For that matter, you could verify the result of gh_api_version() at that time also. > + > + msgq->tx_ghrsc = tx_ghrsc; > + msgq->rx_ghrsc = rx_ghrsc; > + > + msgq->mbox.dev = parent; > + msgq->mbox.ops = &gh_msgq_ops; > + msgq->mbox.num_chans = 1; > + msgq->mbox.txdone_irq = true; > + msgq->mbox.chans = kcalloc(msgq->mbox.num_chans, sizeof(*msgq->mbox.chans), GFP_KERNEL); From what I can tell, you will always use exactly one mailbox channel. So you could just do kzalloc(sizeof()...). > + if (!msgq->mbox.chans) > + return -ENOMEM; > + > + if (msgq->tx_ghrsc) { if (tx_ghrsc) { The irq field is assumed to be valid. Are there any sanity checks you could perform? Again this is only used for the resource manager right now, so maybe it's OK. > + ret = request_irq(msgq->tx_ghrsc->irq, gh_msgq_tx_irq_handler, 0, "gh_msgq_tx", ret = request_irq(tx_ghrsc->irq, ... > + msgq); > + if (ret) > + goto err_chans; > + } > + > + if (msgq->rx_ghrsc) { > + ret = request_threaded_irq(msgq->rx_ghrsc->irq, NULL, gh_msgq_rx_irq_handler, > + IRQF_ONESHOT, "gh_msgq_rx", msgq); > + if (ret) > + goto err_tx_irq; > + } > + > + tasklet_setup(&msgq->txdone_tasklet, gh_msgq_txdone_tasklet); > + > + ret = mbox_controller_register(&msgq->mbox); > + if (ret) > + goto err_rx_irq; > + > + ret = mbox_bind_client(gh_msgq_chan(msgq), cl); > + if (ret) > + goto err_mbox; > + > + return 0; > +err_mbox: > + mbox_controller_unregister(&msgq->mbox); > +err_rx_irq: > + if (msgq->rx_ghrsc) > + free_irq(msgq->rx_ghrsc->irq, msgq); > +err_tx_irq: > + if (msgq->tx_ghrsc) > + free_irq(msgq->tx_ghrsc->irq, msgq); > +err_chans: > + kfree(msgq->mbox.chans); > + return ret; > +} > +EXPORT_SYMBOL_GPL(gh_msgq_init); > + > +void gh_msgq_remove(struct gh_msgq *msgq) > +{ Is there any need to un-bind the client? > + mbox_controller_unregister(&msgq->mbox); > + > + if (msgq->rx_ghrsc) > + free_irq(msgq->rx_ghrsc->irq, msgq); > + > + if (msgq->tx_ghrsc) > + free_irq(msgq->tx_ghrsc->irq, msgq); > + > + kfree(msgq->mbox.chans); > +} > +EXPORT_SYMBOL_GPL(gh_msgq_remove); > + > +MODULE_LICENSE("GPL"); > +MODULE_DESCRIPTION("Gunyah Message Queue Driver"); > diff --git a/include/linux/gunyah.h b/include/linux/gunyah.h > index cb6df4eec5c2..2e13669c6363 100644 > --- a/include/linux/gunyah.h > +++ b/include/linux/gunyah.h > @@ -8,11 +8,67 @@ > > #include <linux/bitfield.h> > #include <linux/errno.h> > +#include <linux/interrupt.h> > #include <linux/limits.h> > +#include <linux/mailbox_controller.h> > +#include <linux/mailbox_client.h> > #include <linux/types.h> > > +/* Follows resource manager's resource types for VM_GET_HYP_RESOURCES */ > +enum gunyah_resource_type { > + GUNYAH_RESOURCE_TYPE_BELL_TX = 0, > + GUNYAH_RESOURCE_TYPE_BELL_RX = 1, > + GUNYAH_RESOURCE_TYPE_MSGQ_TX = 2, > + GUNYAH_RESOURCE_TYPE_MSGQ_RX = 3, > + GUNYAH_RESOURCE_TYPE_VCPU = 4, The maximum value here must fit in 8 bits. I guess there's no risk right now of using that up, but you use negative values in some cases elsewhere. > +}; > + > +struct gunyah_resource { > + enum gunyah_resource_type type; > + u64 capid; > + int irq; request_irq() defines the IRQ value to be an unsigned int. > +}; > + > +/** > + * Gunyah Message Queues > + */ > + > +#define GH_MSGQ_MAX_MSG_SIZE 240 > + > +struct gh_msgq_tx_data { > + size_t length; > + bool push; > + char data[]; > +}; > + > +struct gh_msgq_rx_data { > + size_t length; > + char data[GH_MSGQ_MAX_MSG_SIZE]; > +}; > + > +struct gh_msgq { > + struct gunyah_resource *tx_ghrsc; > + struct gunyah_resource *rx_ghrsc; > + > + /* msgq private */ > + int last_ret; /* Linux error, not GH_STATUS_* */ > + struct mbox_controller mbox; > + struct tasklet_struct txdone_tasklet; Can the msgq_client be embedded here too? (I don't really know whether msgq and msgq_client are one-to one.) > +}; > + > + > +int gh_msgq_init(struct device *parent, struct gh_msgq *msgq, struct mbox_client *cl, > + struct gunyah_resource *tx_ghrsc, struct gunyah_resource *rx_ghrsc); > +void gh_msgq_remove(struct gh_msgq *msgq); I suggested: int gh_msgq_send(struct gh_msgq, struct gh_msgq_tx_data *data); -Alex > + > +static inline struct mbox_chan *gh_msgq_chan(struct gh_msgq *msgq) > +{ > + return &msgq->mbox.chans[0]; > +} > + > /******************************************************************************/ > /* Common arch-independent definitions for Gunyah hypercalls */ > + > #define GH_CAPID_INVAL U64_MAX > #define GH_VMID_ROOT_VM 0xff >
On 2/23/2023 2:25 AM, Srinivas Kandagatla wrote: > > > On 23/02/2023 00:15, Elliot Berman wrote: >> >> >> On 2/20/2023 5:59 AM, Srinivas Kandagatla wrote: >>> >>> >>> On 14/02/2023 21:23, Elliot Berman wrote: >>>> Gunyah message queues are a unidirectional inter-VM pipe for >>>> messages up >>>> to 1024 bytes. This driver supports pairing a receiver message queue >>>> and >>>> a transmitter message queue to expose a single mailbox channel. >>>> >>>> Signed-off-by: Elliot Berman <quic_eberman@quicinc.com> >>>> --- >>>> Documentation/virt/gunyah/message-queue.rst | 8 + >>>> drivers/mailbox/Makefile | 2 + >>>> drivers/mailbox/gunyah-msgq.c | 214 >>>> ++++++++++++++++++++ >>>> include/linux/gunyah.h | 56 +++++ >>>> 4 files changed, 280 insertions(+) >>>> create mode 100644 drivers/mailbox/gunyah-msgq.c >>>> >>>> diff --git a/Documentation/virt/gunyah/message-queue.rst >>>> b/Documentation/virt/gunyah/message-queue.rst >>>> index 0667b3eb1ff9..082085e981e0 100644 >>>> --- a/Documentation/virt/gunyah/message-queue.rst >>>> +++ b/Documentation/virt/gunyah/message-queue.rst >>>> @@ -59,3 +59,11 @@ vIRQ: two TX message queues will have two vIRQs >>>> (and two capability IDs). >>>> | | | | | | >>>> | | | | | | >>>> +---------------+ +-----------------+ +---------------+ >>>> + >>>> +Gunyah message queues are exposed as mailboxes. To create the >>>> mailbox, create >>>> +a mbox_client and call `gh_msgq_init`. On receipt of the RX_READY >>>> interrupt, >>>> +all messages in the RX message queue are read and pushed via the >>>> `rx_callback` >>>> +of the registered mbox_client. >>>> + >>>> +.. kernel-doc:: drivers/mailbox/gunyah-msgq.c >>>> + :identifiers: gh_msgq_init >>>> diff --git a/drivers/mailbox/Makefile b/drivers/mailbox/Makefile >>>> index fc9376117111..5f929bb55e9a 100644 >>>> --- a/drivers/mailbox/Makefile >>>> +++ b/drivers/mailbox/Makefile >>>> @@ -55,6 +55,8 @@ obj-$(CONFIG_MTK_CMDQ_MBOX) += mtk-cmdq-mailbox.o >>>> obj-$(CONFIG_ZYNQMP_IPI_MBOX) += zynqmp-ipi-mailbox.o >>>> +obj-$(CONFIG_GUNYAH) += gunyah-msgq.o >>> >>> Why are we reusing CONFIG_GUNYAH Kconfig symbol for mailbox, why not >>> CONFIG_GUNYAH_MBOX? >>> >> >> There was some previous discussion about this: >> >> https://lore.kernel.org/all/2a7bb5f2-1286-b661-659a-a5037150eae8@quicinc.com/ >> >>>> + >>>> obj-$(CONFIG_SUN6I_MSGBOX) += sun6i-msgbox.o >>>> obj-$(CONFIG_SPRD_MBOX) += sprd-mailbox.o >>>> diff --git a/drivers/mailbox/gunyah-msgq.c >>>> b/drivers/mailbox/gunyah-msgq.c >>>> new file mode 100644 >>>> index 000000000000..03ffaa30ce9b >>>> --- /dev/null >>>> +++ b/drivers/mailbox/gunyah-msgq.c >>>> @@ -0,0 +1,214 @@ >>>> +// SPDX-License-Identifier: GPL-2.0-only >>>> +/* >>>> + * Copyright (c) 2022-2023 Qualcomm Innovation Center, Inc. All >>>> rights reserved. >>>> + */ >>>> + >>>> +#include <linux/mailbox_controller.h> >>>> +#include <linux/module.h> >>>> +#include <linux/interrupt.h> >>>> +#include <linux/gunyah.h> >>>> +#include <linux/printk.h> >>>> +#include <linux/init.h> >>>> +#include <linux/slab.h> >>>> +#include <linux/wait.h> >>> >>> ... >>> >>>> +/* Fired when message queue transitions from "full" to "space >>>> available" to send messages */ >>>> +static irqreturn_t gh_msgq_tx_irq_handler(int irq, void *data) >>>> +{ >>>> + struct gh_msgq *msgq = data; >>>> + >>>> + mbox_chan_txdone(gh_msgq_chan(msgq), 0); >>>> + >>>> + return IRQ_HANDLED; >>>> +} >>>> + >>>> +/* Fired after sending message and hypercall told us there was more >>>> space available. */ >>>> +static void gh_msgq_txdone_tasklet(struct tasklet_struct *tasklet) >>> >>> Tasklets have been long deprecated, consider using workqueues in this >>> particular case. >>> >> >> Workqueues have higher latency and tasklets came as recommendation >> from Jassi. drivers/mailbox/imx-mailbox.c uses tasklets in the same way. >> >> I did some quick unscientific measurements of ~1000x samples. The >> median latency for resource manager went from 25.5 us (tasklet) to 26 >> us (workqueue) (2% slower). The mean went from 28.7 us to 32.5 us (13% >> slower). Obviously, the outliers for workqueues were much more extreme. > > TBH, this is expected because we are only testing resource manager, Note > the advantage that you will see shifting from tasket to workqueues is > on overall system latencies and some drivers performance that need to > react to events. > > please take some time to read this nice article about this > https://lwn.net/Articles/830964/ > Hmm, this article is from 2020 and there was another effort in 2007. Neither seems to have succeeded. I'd like to stick to same mechanisms as other mailbox controllers. Jassi, do you have any preferences? Thanks, Elliot
On 23/02/2023 23:15, Elliot Berman wrote: > > > On 2/23/2023 2:25 AM, Srinivas Kandagatla wrote: >> >> >> On 23/02/2023 00:15, Elliot Berman wrote: >>> >>> >>> On 2/20/2023 5:59 AM, Srinivas Kandagatla wrote: >>>> >>>> >>>> On 14/02/2023 21:23, Elliot Berman wrote: >>>>> Gunyah message queues are a unidirectional inter-VM pipe for >>>>> messages up >>>>> to 1024 bytes. This driver supports pairing a receiver message >>>>> queue and >>>>> a transmitter message queue to expose a single mailbox channel. >>>>> >>>>> Signed-off-by: Elliot Berman <quic_eberman@quicinc.com> >>>>> --- >>>>> Documentation/virt/gunyah/message-queue.rst | 8 + >>>>> drivers/mailbox/Makefile | 2 + >>>>> drivers/mailbox/gunyah-msgq.c | 214 >>>>> ++++++++++++++++++++ >>>>> include/linux/gunyah.h | 56 +++++ >>>>> 4 files changed, 280 insertions(+) >>>>> create mode 100644 drivers/mailbox/gunyah-msgq.c >>>>> >>>>> diff --git a/Documentation/virt/gunyah/message-queue.rst >>>>> b/Documentation/virt/gunyah/message-queue.rst >>>>> index 0667b3eb1ff9..082085e981e0 100644 >>>>> --- a/Documentation/virt/gunyah/message-queue.rst >>>>> +++ b/Documentation/virt/gunyah/message-queue.rst >>>>> @@ -59,3 +59,11 @@ vIRQ: two TX message queues will have two vIRQs >>>>> (and two capability IDs). >>>>> | | | | >>>>> | | >>>>> | | | | >>>>> | | >>>>> +---------------+ +-----------------+ >>>>> +---------------+ >>>>> + >>>>> +Gunyah message queues are exposed as mailboxes. To create the >>>>> mailbox, create >>>>> +a mbox_client and call `gh_msgq_init`. On receipt of the RX_READY >>>>> interrupt, >>>>> +all messages in the RX message queue are read and pushed via the >>>>> `rx_callback` >>>>> +of the registered mbox_client. >>>>> + >>>>> +.. kernel-doc:: drivers/mailbox/gunyah-msgq.c >>>>> + :identifiers: gh_msgq_init >>>>> diff --git a/drivers/mailbox/Makefile b/drivers/mailbox/Makefile >>>>> index fc9376117111..5f929bb55e9a 100644 >>>>> --- a/drivers/mailbox/Makefile >>>>> +++ b/drivers/mailbox/Makefile >>>>> @@ -55,6 +55,8 @@ obj-$(CONFIG_MTK_CMDQ_MBOX) += mtk-cmdq-mailbox.o >>>>> obj-$(CONFIG_ZYNQMP_IPI_MBOX) += zynqmp-ipi-mailbox.o >>>>> +obj-$(CONFIG_GUNYAH) += gunyah-msgq.o >>>> >>>> Why are we reusing CONFIG_GUNYAH Kconfig symbol for mailbox, why not >>>> CONFIG_GUNYAH_MBOX? >>>> >>> >>> There was some previous discussion about this: >>> >>> https://lore.kernel.org/all/2a7bb5f2-1286-b661-659a-a5037150eae8@quicinc.com/ >>> >>>>> + >>>>> obj-$(CONFIG_SUN6I_MSGBOX) += sun6i-msgbox.o >>>>> obj-$(CONFIG_SPRD_MBOX) += sprd-mailbox.o >>>>> diff --git a/drivers/mailbox/gunyah-msgq.c >>>>> b/drivers/mailbox/gunyah-msgq.c >>>>> new file mode 100644 >>>>> index 000000000000..03ffaa30ce9b >>>>> --- /dev/null >>>>> +++ b/drivers/mailbox/gunyah-msgq.c >>>>> @@ -0,0 +1,214 @@ >>>>> +// SPDX-License-Identifier: GPL-2.0-only >>>>> +/* >>>>> + * Copyright (c) 2022-2023 Qualcomm Innovation Center, Inc. All >>>>> rights reserved. >>>>> + */ >>>>> + >>>>> +#include <linux/mailbox_controller.h> >>>>> +#include <linux/module.h> >>>>> +#include <linux/interrupt.h> >>>>> +#include <linux/gunyah.h> >>>>> +#include <linux/printk.h> >>>>> +#include <linux/init.h> >>>>> +#include <linux/slab.h> >>>>> +#include <linux/wait.h> >>>> >>>> ... >>>> >>>>> +/* Fired when message queue transitions from "full" to "space >>>>> available" to send messages */ >>>>> +static irqreturn_t gh_msgq_tx_irq_handler(int irq, void *data) >>>>> +{ >>>>> + struct gh_msgq *msgq = data; >>>>> + >>>>> + mbox_chan_txdone(gh_msgq_chan(msgq), 0); >>>>> + >>>>> + return IRQ_HANDLED; >>>>> +} >>>>> + >>>>> +/* Fired after sending message and hypercall told us there was >>>>> more space available. */ >>>>> +static void gh_msgq_txdone_tasklet(struct tasklet_struct *tasklet) >>>> >>>> Tasklets have been long deprecated, consider using workqueues in >>>> this particular case. >>>> >>> >>> Workqueues have higher latency and tasklets came as recommendation >>> from Jassi. drivers/mailbox/imx-mailbox.c uses tasklets in the same way. >>> >>> I did some quick unscientific measurements of ~1000x samples. The >>> median latency for resource manager went from 25.5 us (tasklet) to 26 >>> us (workqueue) (2% slower). The mean went from 28.7 us to 32.5 us >>> (13% slower). Obviously, the outliers for workqueues were much more >>> extreme. >> >> TBH, this is expected because we are only testing resource manager, >> Note the advantage that you will see shifting from tasket to >> workqueues is on overall system latencies and some drivers performance >> that need to react to events. >> >> please take some time to read this nice article about this >> https://lwn.net/Articles/830964/ >> > > Hmm, this article is from 2020 and there was another effort in 2007. > Neither seems to have succeeded. I'd like to stick to same mechanisms as > other mailbox controllers. I don't want to block this series because of this. We will have more opportunity to improve this once some system wide profiling is done. AFAIU, In this system we will have atleast 2 tasklets between VM and RM and 2 per inter-vm, so if the number of tasklets increase in the system will be potentially spending more time in soft irq handling it. At somepoint in time its good to get some profiling done using bcc/softirqs to see how much time is spent on softirqs. --srini > > Jassi, do you have any preferences? > > Thanks, > Elliot > >
On 2/23/2023 1:11 PM, Alex Elder wrote: > On 2/14/23 3:23 PM, Elliot Berman wrote: >> Gunyah message queues are a unidirectional inter-VM pipe for messages up >> to 1024 bytes. This driver supports pairing a receiver message queue and >> a transmitter message queue to expose a single mailbox channel. >> >> Signed-off-by: Elliot Berman <quic_eberman@quicinc.com> >> --- >> Documentation/virt/gunyah/message-queue.rst | 8 + >> drivers/mailbox/Makefile | 2 + >> drivers/mailbox/gunyah-msgq.c | 214 ++++++++++++++++++++ >> include/linux/gunyah.h | 56 +++++ >> 4 files changed, 280 insertions(+) >> create mode 100644 drivers/mailbox/gunyah-msgq.c >> >> diff --git a/Documentation/virt/gunyah/message-queue.rst >> b/Documentation/virt/gunyah/message-queue.rst >> index 0667b3eb1ff9..082085e981e0 100644 >> --- a/Documentation/virt/gunyah/message-queue.rst >> +++ b/Documentation/virt/gunyah/message-queue.rst >> @@ -59,3 +59,11 @@ vIRQ: two TX message queues will have two vIRQs >> (and two capability IDs). >> | | | | >> | | >> | | | | >> | | >> +---------------+ +-----------------+ >> +---------------+ >> + >> +Gunyah message queues are exposed as mailboxes. To create the >> mailbox, create >> +a mbox_client and call `gh_msgq_init`. On receipt of the RX_READY >> interrupt, >> +all messages in the RX message queue are read and pushed via the >> `rx_callback` >> +of the registered mbox_client. >> + >> +.. kernel-doc:: drivers/mailbox/gunyah-msgq.c >> + :identifiers: gh_msgq_init >> diff --git a/drivers/mailbox/Makefile b/drivers/mailbox/Makefile >> index fc9376117111..5f929bb55e9a 100644 >> --- a/drivers/mailbox/Makefile >> +++ b/drivers/mailbox/Makefile >> @@ -55,6 +55,8 @@ obj-$(CONFIG_MTK_CMDQ_MBOX) += mtk-cmdq-mailbox.o >> obj-$(CONFIG_ZYNQMP_IPI_MBOX) += zynqmp-ipi-mailbox.o >> +obj-$(CONFIG_GUNYAH) += gunyah-msgq.o >> + >> obj-$(CONFIG_SUN6I_MSGBOX) += sun6i-msgbox.o >> obj-$(CONFIG_SPRD_MBOX) += sprd-mailbox.o >> diff --git a/drivers/mailbox/gunyah-msgq.c >> b/drivers/mailbox/gunyah-msgq.c >> new file mode 100644 >> index 000000000000..03ffaa30ce9b >> --- /dev/null >> +++ b/drivers/mailbox/gunyah-msgq.c > > You use a dash in this source file name, but an underscore > everywhere else. Unless there's a good reason to do this, > please be consistent (use "gunyah_msgq.c"). > >> @@ -0,0 +1,214 @@ >> +// SPDX-License-Identifier: GPL-2.0-only >> +/* >> + * Copyright (c) 2022-2023 Qualcomm Innovation Center, Inc. All >> rights reserved. >> + */ >> + >> +#include <linux/mailbox_controller.h> >> +#include <linux/module.h> >> +#include <linux/interrupt.h> >> +#include <linux/gunyah.h> >> +#include <linux/printk.h> >> +#include <linux/init.h> >> +#include <linux/slab.h> >> +#include <linux/wait.h> >> + >> +#define mbox_chan_to_msgq(chan) (container_of(chan->mbox, struct >> gh_msgq, mbox)) >> + >> +static irqreturn_t gh_msgq_rx_irq_handler(int irq, void *data) >> +{ >> + struct gh_msgq *msgq = data; >> + struct gh_msgq_rx_data rx_data; >> + enum gh_error err; >> + bool ready = true; >> + >> + while (ready) { >> + err = gh_hypercall_msgq_recv(msgq->rx_ghrsc->capid, >> + (uintptr_t)&rx_data.data, sizeof(rx_data.data), >> + &rx_data.length, &ready); >> + if (err != GH_ERROR_OK) { >> + if (err != GH_ERROR_MSGQUEUE_EMPTY) > > Srini mentioned something about this too. In many > (all?) cases, there is a device pointer available, > so you should use dev_*() functions rather than pr_*(). > > In this particular case, I'm not sure why/when the > mbox.dev pointer would be null. Also, dev_*() handles > the case of a null device pointer, and it reports the > device name (just as you do here). > >> + pr_warn("Failed to receive data from msgq for %s: %d\n", >> + msgq->mbox.dev ? dev_name(msgq->mbox.dev) : "", >> err); >> + break; >> + } >> + mbox_chan_received_data(gh_msgq_chan(msgq), &rx_data); >> + } >> + >> + return IRQ_HANDLED; >> +} >> + >> +/* Fired when message queue transitions from "full" to "space >> available" to send messages */ >> +static irqreturn_t gh_msgq_tx_irq_handler(int irq, void *data) >> +{ >> + struct gh_msgq *msgq = data; >> + >> + mbox_chan_txdone(gh_msgq_chan(msgq), 0); >> + >> + return IRQ_HANDLED; >> +} >> + >> +/* Fired after sending message and hypercall told us there was more >> space available. */ >> +static void gh_msgq_txdone_tasklet(struct tasklet_struct *tasklet) >> +{ >> + struct gh_msgq *msgq = container_of(tasklet, struct gh_msgq, >> txdone_tasklet); >> + >> + mbox_chan_txdone(gh_msgq_chan(msgq), msgq->last_ret); >> +} >> + >> +static int gh_msgq_send_data(struct mbox_chan *chan, void *data) >> +{ >> + struct gh_msgq *msgq = mbox_chan_to_msgq(chan); >> + struct gh_msgq_tx_data *msgq_data = data; >> + u64 tx_flags = 0; >> + enum gh_error gh_error; > > Above you named the variable "err". It helps readability > if you use a very consistent naming convention for variables > of a certain type when they are used a lot. > >> + bool ready; >> + >> + if (msgq_data->push) >> + tx_flags |= GH_HYPERCALL_MSGQ_TX_FLAGS_PUSH; >> + >> + gh_error = gh_hypercall_msgq_send(msgq->tx_ghrsc->capid, >> msgq_data->length, >> + (uintptr_t)msgq_data->data, tx_flags, &ready); >> + >> + /** >> + * unlikely because Linux tracks state of msgq and should not try to >> + * send message when msgq is full. >> + */ >> + if (unlikely(gh_error == GH_ERROR_MSGQUEUE_FULL)) >> + return -EAGAIN; >> + >> + /** >> + * Propagate all other errors to client. If we return error to >> mailbox >> + * framework, then no other messages can be sent and nobody will >> know >> + * to retry this message. >> + */ >> + msgq->last_ret = gh_remap_error(gh_error); >> + >> + /** >> + * This message was successfully sent, but message queue isn't >> ready to >> + * receive more messages because it's now full. Mailbox framework > > Maybe: s/receive/accept/ > >> + * requires that we only report that message was transmitted when >> + * we're ready to transmit another message. We'll get that in the >> form >> + * of tx IRQ once the other side starts to drain the msgq. >> + */ >> + if (gh_error == GH_ERROR_OK && !ready) >> + return 0; >> + >> + /** >> + * We can send more messages. Mailbox framework requires that tx >> done >> + * happens asynchronously to sending the message. Gunyah message >> queues >> + * tell us right away on the hypercall return whether we can send >> more >> + * messages. To work around this, defer the txdone to a tasklet. >> + */ >> + tasklet_schedule(&msgq->txdone_tasklet); >> + >> + return 0; >> +} >> + >> +static struct mbox_chan_ops gh_msgq_ops = { >> + .send_data = gh_msgq_send_data, >> +}; >> + >> +/** >> + * gh_msgq_init() - Initialize a Gunyah message queue with an >> mbox_client >> + * @parent: optional, device parent used for the mailbox controller >> + * @msgq: Pointer to the gh_msgq to initialize >> + * @cl: A mailbox client to bind to the mailbox channel that the >> message queue creates >> + * @tx_ghrsc: optional, the transmission side of the message queue >> + * @rx_ghrsc: optional, the receiving side of the message queue >> + * >> + * At least one of tx_ghrsc and rx_ghrsc should be not NULL. Most >> message queue use cases come with > > s/should be/must be/ > >> + * a pair of message queues to facilitate bidirectional >> communication. When tx_ghrsc is set, >> + * the client can send messages with >> mbox_send_message(gh_msgq_chan(msgq), msg). When rx_ghrsc >> + * is set, the mbox_client should register an .rx_callback() and the >> message queue driver will > > s/should register/must register/ > > A general comment on this code is that you sort of half define > a Gunyah message queue API. You define an initialization > function and an exit function, but you also expose the fact > that you use the mailbox framework in implementation. This > despite avoiding defining it as an mbox in the DTS file. > > It might be hard to avoid that I guess. But to me it would be > nice if there were a more distinct Gunyah message queue API, > which would provide a send_message() function, for example. > And in that case, perhaps you would pass in the tx_done and/or > rx_data callbacks to this function (since they're required). I can write a wrapper for send_message, but I think it limits the code re-use of mailbox framework. > > All that said, this is (currently?) only used by the resource > manager, so making a beautiful API might not be that important. > Do you envision this being used to communicate with other VMs > in the future? > >> + * push all available messages upon receiving the RX ready interrupt. >> The messages should be > > Maybe: s/push/deliver/ > >> + * consumed or copied by the client right away as the gh_msgq_rx_data >> will be replaced/destroyed >> + * after the callback. >> + * >> + * Returns - 0 on success, negative otherwise >> + */ >> +int gh_msgq_init(struct device *parent, struct gh_msgq *msgq, struct >> mbox_client *cl, >> + struct gunyah_resource *tx_ghrsc, struct gunyah_resource >> *rx_ghrsc) >> +{ >> + int ret; >> + >> + /* Must have at least a tx_ghrsc or rx_ghrsc and that they are >> the right device types */ >> + if ((!tx_ghrsc && !rx_ghrsc) || >> + (tx_ghrsc && tx_ghrsc->type != GUNYAH_RESOURCE_TYPE_MSGQ_TX) || >> + (rx_ghrsc && rx_ghrsc->type != GUNYAH_RESOURCE_TYPE_MSGQ_RX)) >> + return -EINVAL; >> + >> + if (gh_api_version() != GUNYAH_API_V1) { >> + pr_err("Unrecognized gunyah version: %u. Currently supported: >> %d\n", >> + gh_api_version(), GUNYAH_API_V1); >> + return -EOPNOTSUPP; >> + } >> + >> + if (!gh_api_has_feature(GH_API_FEATURE_MSGQUEUE)) >> + return -EOPNOTSUPP; > > Can Gunyah even function if it doesn't have the MSGQUEUE feature? > Will there ever be a Gunyah implementation that does not support > it? Perhaps this test could be done in gunyah_init() instead. I don't think we will ever have a Gunyah implementation that doesn't support message queues. Perhaps some long distant Gunyah will use IPC mechanism X instead of message queues and the message queue support is dropped. > > For that matter, you could verify the result of gh_api_version() > at that time also. > Moved the gh_api_version() check to gunyah_init() >> + >> + msgq->tx_ghrsc = tx_ghrsc; >> + msgq->rx_ghrsc = rx_ghrsc; >> + >> + msgq->mbox.dev = parent; >> + msgq->mbox.ops = &gh_msgq_ops; >> + msgq->mbox.num_chans = 1; >> + msgq->mbox.txdone_irq = true; >> + msgq->mbox.chans = kcalloc(msgq->mbox.num_chans, >> sizeof(*msgq->mbox.chans), GFP_KERNEL); > > From what I can tell, you will always use exactly one mailbox channel. > So you could just do kzalloc(sizeof()...). > If it's all the same, I'd like to keep it as kcalloc because chans is expected to be an array with num_chans size. It seems more correct to use kcalloc. >> + if (!msgq->mbox.chans) >> + return -ENOMEM; >> + >> + if (msgq->tx_ghrsc) { > > if (tx_ghrsc) { > > The irq field is assumed to be valid. Are there any > sanity checks you could perform? Again this is only > used for the resource manager right now, so maybe > it's OK. > We should safely assume irq field is valid. If we need to be skeptical of irq, we'd also need to be skeptical of capid and there's not validity check to perform there. struct gunyah_resource's are either filled from DT (in this case) or would be created by resource manager which does validity checks. >> + ret = request_irq(msgq->tx_ghrsc->irq, >> gh_msgq_tx_irq_handler, 0, "gh_msgq_tx", > > ret = request_irq(tx_ghrsc->irq, ... > > >> + msgq); >> + if (ret) >> + goto err_chans; >> + } >> + >> + if (msgq->rx_ghrsc) { >> + ret = request_threaded_irq(msgq->rx_ghrsc->irq, NULL, >> gh_msgq_rx_irq_handler, >> + IRQF_ONESHOT, "gh_msgq_rx", msgq); >> + if (ret) >> + goto err_tx_irq; >> + } >> + >> + tasklet_setup(&msgq->txdone_tasklet, gh_msgq_txdone_tasklet); >> + >> + ret = mbox_controller_register(&msgq->mbox); >> + if (ret) >> + goto err_rx_irq; >> + >> + ret = mbox_bind_client(gh_msgq_chan(msgq), cl); > > >> + if (ret) >> + goto err_mbox; >> + >> + return 0; >> +err_mbox: >> + mbox_controller_unregister(&msgq->mbox); >> +err_rx_irq: >> + if (msgq->rx_ghrsc) >> + free_irq(msgq->rx_ghrsc->irq, msgq); >> +err_tx_irq: >> + if (msgq->tx_ghrsc) >> + free_irq(msgq->tx_ghrsc->irq, msgq); >> +err_chans: >> + kfree(msgq->mbox.chans); >> + return ret; >> +} >> +EXPORT_SYMBOL_GPL(gh_msgq_init); >> + >> +void gh_msgq_remove(struct gh_msgq *msgq) >> +{ > > Is there any need to un-bind the client? > I was leaving un-binding the client to the client (RM). >> + mbox_controller_unregister(&msgq->mbox); >> + >> + if (msgq->rx_ghrsc) >> + free_irq(msgq->rx_ghrsc->irq, msgq); >> + >> + if (msgq->tx_ghrsc) >> + free_irq(msgq->tx_ghrsc->irq, msgq); >> + >> + kfree(msgq->mbox.chans); >> +} >> +EXPORT_SYMBOL_GPL(gh_msgq_remove); >> + >> +MODULE_LICENSE("GPL"); >> +MODULE_DESCRIPTION("Gunyah Message Queue Driver"); >> diff --git a/include/linux/gunyah.h b/include/linux/gunyah.h >> index cb6df4eec5c2..2e13669c6363 100644 >> --- a/include/linux/gunyah.h >> +++ b/include/linux/gunyah.h >> @@ -8,11 +8,67 @@ >> #include <linux/bitfield.h> >> #include <linux/errno.h> >> +#include <linux/interrupt.h> >> #include <linux/limits.h> >> +#include <linux/mailbox_controller.h> >> +#include <linux/mailbox_client.h> >> #include <linux/types.h> >> +/* Follows resource manager's resource types for VM_GET_HYP_RESOURCES */ >> +enum gunyah_resource_type { >> + GUNYAH_RESOURCE_TYPE_BELL_TX = 0, >> + GUNYAH_RESOURCE_TYPE_BELL_RX = 1, >> + GUNYAH_RESOURCE_TYPE_MSGQ_TX = 2, >> + GUNYAH_RESOURCE_TYPE_MSGQ_RX = 3, >> + GUNYAH_RESOURCE_TYPE_VCPU = 4, > > The maximum value here must fit in 8 bits. I guess > there's no risk right now of using that up, but you > use negative values in some cases elsewhere. > >> +}; >> + >> +struct gunyah_resource { >> + enum gunyah_resource_type type; >> + u64 capid; >> + int irq; > > request_irq() defines the IRQ value to be an unsigned int. > Done. >> +}; >> + >> +/** >> + * Gunyah Message Queues >> + */ >> + >> +#define GH_MSGQ_MAX_MSG_SIZE 240 >> + >> +struct gh_msgq_tx_data { >> + size_t length; >> + bool push; >> + char data[]; >> +}; >> + >> +struct gh_msgq_rx_data { >> + size_t length; >> + char data[GH_MSGQ_MAX_MSG_SIZE]; >> +}; >> + >> +struct gh_msgq { >> + struct gunyah_resource *tx_ghrsc; >> + struct gunyah_resource *rx_ghrsc; >> + >> + /* msgq private */ >> + int last_ret; /* Linux error, not GH_STATUS_* */ >> + struct mbox_controller mbox; >> + struct tasklet_struct txdone_tasklet; > > Can the msgq_client be embedded here too? (I don't really > know whether msgq and msgq_client are one-to one.) > They are one-to-one. I can embed the struct in the struct gh_msgq and drop the kcalloc. Thanks, Elliot >> +}; >> + >> + >> +int gh_msgq_init(struct device *parent, struct gh_msgq *msgq, struct >> mbox_client *cl, >> + struct gunyah_resource *tx_ghrsc, struct gunyah_resource >> *rx_ghrsc); >> +void gh_msgq_remove(struct gh_msgq *msgq); > > I suggested: > > int gh_msgq_send(struct gh_msgq, struct gh_msgq_tx_data *data); > > -Alex > >> + >> +static inline struct mbox_chan *gh_msgq_chan(struct gh_msgq *msgq) >> +{ >> + return &msgq->mbox.chans[0]; >> +} >> + >> >> /******************************************************************************/ >> /* Common arch-independent definitions for Gunyah >> hypercalls */ >> + >> #define GH_CAPID_INVAL U64_MAX >> #define GH_VMID_ROOT_VM 0xff >
diff --git a/Documentation/virt/gunyah/message-queue.rst b/Documentation/virt/gunyah/message-queue.rst index 0667b3eb1ff9..082085e981e0 100644 --- a/Documentation/virt/gunyah/message-queue.rst +++ b/Documentation/virt/gunyah/message-queue.rst @@ -59,3 +59,11 @@ vIRQ: two TX message queues will have two vIRQs (and two capability IDs). | | | | | | | | | | | | +---------------+ +-----------------+ +---------------+ + +Gunyah message queues are exposed as mailboxes. To create the mailbox, create +a mbox_client and call `gh_msgq_init`. On receipt of the RX_READY interrupt, +all messages in the RX message queue are read and pushed via the `rx_callback` +of the registered mbox_client. + +.. kernel-doc:: drivers/mailbox/gunyah-msgq.c + :identifiers: gh_msgq_init diff --git a/drivers/mailbox/Makefile b/drivers/mailbox/Makefile index fc9376117111..5f929bb55e9a 100644 --- a/drivers/mailbox/Makefile +++ b/drivers/mailbox/Makefile @@ -55,6 +55,8 @@ obj-$(CONFIG_MTK_CMDQ_MBOX) += mtk-cmdq-mailbox.o obj-$(CONFIG_ZYNQMP_IPI_MBOX) += zynqmp-ipi-mailbox.o +obj-$(CONFIG_GUNYAH) += gunyah-msgq.o + obj-$(CONFIG_SUN6I_MSGBOX) += sun6i-msgbox.o obj-$(CONFIG_SPRD_MBOX) += sprd-mailbox.o diff --git a/drivers/mailbox/gunyah-msgq.c b/drivers/mailbox/gunyah-msgq.c new file mode 100644 index 000000000000..03ffaa30ce9b --- /dev/null +++ b/drivers/mailbox/gunyah-msgq.c @@ -0,0 +1,214 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * Copyright (c) 2022-2023 Qualcomm Innovation Center, Inc. All rights reserved. + */ + +#include <linux/mailbox_controller.h> +#include <linux/module.h> +#include <linux/interrupt.h> +#include <linux/gunyah.h> +#include <linux/printk.h> +#include <linux/init.h> +#include <linux/slab.h> +#include <linux/wait.h> + +#define mbox_chan_to_msgq(chan) (container_of(chan->mbox, struct gh_msgq, mbox)) + +static irqreturn_t gh_msgq_rx_irq_handler(int irq, void *data) +{ + struct gh_msgq *msgq = data; + struct gh_msgq_rx_data rx_data; + enum gh_error err; + bool ready = true; + + while (ready) { + err = gh_hypercall_msgq_recv(msgq->rx_ghrsc->capid, + (uintptr_t)&rx_data.data, sizeof(rx_data.data), + &rx_data.length, &ready); + if (err != GH_ERROR_OK) { + if (err != GH_ERROR_MSGQUEUE_EMPTY) + pr_warn("Failed to receive data from msgq for %s: %d\n", + msgq->mbox.dev ? dev_name(msgq->mbox.dev) : "", err); + break; + } + mbox_chan_received_data(gh_msgq_chan(msgq), &rx_data); + } + + return IRQ_HANDLED; +} + +/* Fired when message queue transitions from "full" to "space available" to send messages */ +static irqreturn_t gh_msgq_tx_irq_handler(int irq, void *data) +{ + struct gh_msgq *msgq = data; + + mbox_chan_txdone(gh_msgq_chan(msgq), 0); + + return IRQ_HANDLED; +} + +/* Fired after sending message and hypercall told us there was more space available. */ +static void gh_msgq_txdone_tasklet(struct tasklet_struct *tasklet) +{ + struct gh_msgq *msgq = container_of(tasklet, struct gh_msgq, txdone_tasklet); + + mbox_chan_txdone(gh_msgq_chan(msgq), msgq->last_ret); +} + +static int gh_msgq_send_data(struct mbox_chan *chan, void *data) +{ + struct gh_msgq *msgq = mbox_chan_to_msgq(chan); + struct gh_msgq_tx_data *msgq_data = data; + u64 tx_flags = 0; + enum gh_error gh_error; + bool ready; + + if (msgq_data->push) + tx_flags |= GH_HYPERCALL_MSGQ_TX_FLAGS_PUSH; + + gh_error = gh_hypercall_msgq_send(msgq->tx_ghrsc->capid, msgq_data->length, + (uintptr_t)msgq_data->data, tx_flags, &ready); + + /** + * unlikely because Linux tracks state of msgq and should not try to + * send message when msgq is full. + */ + if (unlikely(gh_error == GH_ERROR_MSGQUEUE_FULL)) + return -EAGAIN; + + /** + * Propagate all other errors to client. If we return error to mailbox + * framework, then no other messages can be sent and nobody will know + * to retry this message. + */ + msgq->last_ret = gh_remap_error(gh_error); + + /** + * This message was successfully sent, but message queue isn't ready to + * receive more messages because it's now full. Mailbox framework + * requires that we only report that message was transmitted when + * we're ready to transmit another message. We'll get that in the form + * of tx IRQ once the other side starts to drain the msgq. + */ + if (gh_error == GH_ERROR_OK && !ready) + return 0; + + /** + * We can send more messages. Mailbox framework requires that tx done + * happens asynchronously to sending the message. Gunyah message queues + * tell us right away on the hypercall return whether we can send more + * messages. To work around this, defer the txdone to a tasklet. + */ + tasklet_schedule(&msgq->txdone_tasklet); + + return 0; +} + +static struct mbox_chan_ops gh_msgq_ops = { + .send_data = gh_msgq_send_data, +}; + +/** + * gh_msgq_init() - Initialize a Gunyah message queue with an mbox_client + * @parent: optional, device parent used for the mailbox controller + * @msgq: Pointer to the gh_msgq to initialize + * @cl: A mailbox client to bind to the mailbox channel that the message queue creates + * @tx_ghrsc: optional, the transmission side of the message queue + * @rx_ghrsc: optional, the receiving side of the message queue + * + * At least one of tx_ghrsc and rx_ghrsc should be not NULL. Most message queue use cases come with + * a pair of message queues to facilitate bidirectional communication. When tx_ghrsc is set, + * the client can send messages with mbox_send_message(gh_msgq_chan(msgq), msg). When rx_ghrsc + * is set, the mbox_client should register an .rx_callback() and the message queue driver will + * push all available messages upon receiving the RX ready interrupt. The messages should be + * consumed or copied by the client right away as the gh_msgq_rx_data will be replaced/destroyed + * after the callback. + * + * Returns - 0 on success, negative otherwise + */ +int gh_msgq_init(struct device *parent, struct gh_msgq *msgq, struct mbox_client *cl, + struct gunyah_resource *tx_ghrsc, struct gunyah_resource *rx_ghrsc) +{ + int ret; + + /* Must have at least a tx_ghrsc or rx_ghrsc and that they are the right device types */ + if ((!tx_ghrsc && !rx_ghrsc) || + (tx_ghrsc && tx_ghrsc->type != GUNYAH_RESOURCE_TYPE_MSGQ_TX) || + (rx_ghrsc && rx_ghrsc->type != GUNYAH_RESOURCE_TYPE_MSGQ_RX)) + return -EINVAL; + + if (gh_api_version() != GUNYAH_API_V1) { + pr_err("Unrecognized gunyah version: %u. Currently supported: %d\n", + gh_api_version(), GUNYAH_API_V1); + return -EOPNOTSUPP; + } + + if (!gh_api_has_feature(GH_API_FEATURE_MSGQUEUE)) + return -EOPNOTSUPP; + + msgq->tx_ghrsc = tx_ghrsc; + msgq->rx_ghrsc = rx_ghrsc; + + msgq->mbox.dev = parent; + msgq->mbox.ops = &gh_msgq_ops; + msgq->mbox.num_chans = 1; + msgq->mbox.txdone_irq = true; + msgq->mbox.chans = kcalloc(msgq->mbox.num_chans, sizeof(*msgq->mbox.chans), GFP_KERNEL); + if (!msgq->mbox.chans) + return -ENOMEM; + + if (msgq->tx_ghrsc) { + ret = request_irq(msgq->tx_ghrsc->irq, gh_msgq_tx_irq_handler, 0, "gh_msgq_tx", + msgq); + if (ret) + goto err_chans; + } + + if (msgq->rx_ghrsc) { + ret = request_threaded_irq(msgq->rx_ghrsc->irq, NULL, gh_msgq_rx_irq_handler, + IRQF_ONESHOT, "gh_msgq_rx", msgq); + if (ret) + goto err_tx_irq; + } + + tasklet_setup(&msgq->txdone_tasklet, gh_msgq_txdone_tasklet); + + ret = mbox_controller_register(&msgq->mbox); + if (ret) + goto err_rx_irq; + + ret = mbox_bind_client(gh_msgq_chan(msgq), cl); + if (ret) + goto err_mbox; + + return 0; +err_mbox: + mbox_controller_unregister(&msgq->mbox); +err_rx_irq: + if (msgq->rx_ghrsc) + free_irq(msgq->rx_ghrsc->irq, msgq); +err_tx_irq: + if (msgq->tx_ghrsc) + free_irq(msgq->tx_ghrsc->irq, msgq); +err_chans: + kfree(msgq->mbox.chans); + return ret; +} +EXPORT_SYMBOL_GPL(gh_msgq_init); + +void gh_msgq_remove(struct gh_msgq *msgq) +{ + mbox_controller_unregister(&msgq->mbox); + + if (msgq->rx_ghrsc) + free_irq(msgq->rx_ghrsc->irq, msgq); + + if (msgq->tx_ghrsc) + free_irq(msgq->tx_ghrsc->irq, msgq); + + kfree(msgq->mbox.chans); +} +EXPORT_SYMBOL_GPL(gh_msgq_remove); + +MODULE_LICENSE("GPL"); +MODULE_DESCRIPTION("Gunyah Message Queue Driver"); diff --git a/include/linux/gunyah.h b/include/linux/gunyah.h index cb6df4eec5c2..2e13669c6363 100644 --- a/include/linux/gunyah.h +++ b/include/linux/gunyah.h @@ -8,11 +8,67 @@ #include <linux/bitfield.h> #include <linux/errno.h> +#include <linux/interrupt.h> #include <linux/limits.h> +#include <linux/mailbox_controller.h> +#include <linux/mailbox_client.h> #include <linux/types.h> +/* Follows resource manager's resource types for VM_GET_HYP_RESOURCES */ +enum gunyah_resource_type { + GUNYAH_RESOURCE_TYPE_BELL_TX = 0, + GUNYAH_RESOURCE_TYPE_BELL_RX = 1, + GUNYAH_RESOURCE_TYPE_MSGQ_TX = 2, + GUNYAH_RESOURCE_TYPE_MSGQ_RX = 3, + GUNYAH_RESOURCE_TYPE_VCPU = 4, +}; + +struct gunyah_resource { + enum gunyah_resource_type type; + u64 capid; + int irq; +}; + +/** + * Gunyah Message Queues + */ + +#define GH_MSGQ_MAX_MSG_SIZE 240 + +struct gh_msgq_tx_data { + size_t length; + bool push; + char data[]; +}; + +struct gh_msgq_rx_data { + size_t length; + char data[GH_MSGQ_MAX_MSG_SIZE]; +}; + +struct gh_msgq { + struct gunyah_resource *tx_ghrsc; + struct gunyah_resource *rx_ghrsc; + + /* msgq private */ + int last_ret; /* Linux error, not GH_STATUS_* */ + struct mbox_controller mbox; + struct tasklet_struct txdone_tasklet; +}; + + +int gh_msgq_init(struct device *parent, struct gh_msgq *msgq, struct mbox_client *cl, + struct gunyah_resource *tx_ghrsc, struct gunyah_resource *rx_ghrsc); +void gh_msgq_remove(struct gh_msgq *msgq); + +static inline struct mbox_chan *gh_msgq_chan(struct gh_msgq *msgq) +{ + return &msgq->mbox.chans[0]; +} + /******************************************************************************/ /* Common arch-independent definitions for Gunyah hypercalls */ + #define GH_CAPID_INVAL U64_MAX #define GH_VMID_ROOT_VM 0xff
Gunyah message queues are a unidirectional inter-VM pipe for messages up to 1024 bytes. This driver supports pairing a receiver message queue and a transmitter message queue to expose a single mailbox channel. Signed-off-by: Elliot Berman <quic_eberman@quicinc.com> --- Documentation/virt/gunyah/message-queue.rst | 8 + drivers/mailbox/Makefile | 2 + drivers/mailbox/gunyah-msgq.c | 214 ++++++++++++++++++++ include/linux/gunyah.h | 56 +++++ 4 files changed, 280 insertions(+) create mode 100644 drivers/mailbox/gunyah-msgq.c