Hello,
This series adds initial support for the Qualcomm specific Modem Host Interface
(MHI) bus in endpoint devices like SDX55 modems. The MHI bus in endpoint devices
communicates with the MHI bus in host machines like x86 over any physical bus
like PCIe. The MHI host support is already in mainline [1] and been used by PCIe
based modems and WLAN devices running vendor code (downstream).
Overview
========
This series aims at adding the MHI support in the endpoint devices with the goal
of getting data connectivity using the mainline kernel running on the modems.
Modems here refer to the combination of an APPS processor (Cortex A grade) and
a baseband processor (DSP). The MHI bus is located in the APPS processor and it
transfers data packets from the baseband processor to the host machine.
The MHI Endpoint (MHI EP) stack proposed here is inspired by the downstream
code written by Qualcomm. But the complete stack is mostly re-written to adapt
to the "bus" framework and made it modular so that it can work with the upstream
subsystems like "PCI Endpoint". The code structure of the MHI endpoint stack
follows the MHI host stack to maintain uniformity.
With this initial MHI EP stack (along with few other drivers), we can establish
the network interface between host and endpoint over the MHI software channels
(IP_SW0) and can do things like IP forwarding, SSH, etc...
Stack Organization
==================
The MHI EP stack has the concept of controller and device drivers as like the
MHI host stack. The MHI EP controller driver can be a PCI Endpoint Function
driver and the MHI device driver can be a MHI EP Networking driver or QRTR
driver. The MHI EP controller driver is tied to the PCI Endpoint subsystem and
handles all bus related activities like mapping the host memory, raising IRQ,
passing link specific events etc... The MHI EP networking driver is tied to the
Networking stack and handles all networking related activities like
sending/receiving the SKBs from netdev, statistics collection etc...
This series only contains the MHI EP code, whereas the PCIe EPF driver and MHI
EP Networking drivers are not yet submitted and can be found here [2]. Though
the MHI EP stack doesn't have the build time dependency, it cannot function
without them.
Test setup
==========
This series has been tested on Telit FN980 TLB board powered by Qualcomm SDX55
(a.k.a X55 modem) and Qualcomm SM8450 based dev board.
For testing the stability and performance, networking tools such as iperf, ssh
and ping are used.
Limitations
===========
We are not _yet_ there to get the data packets from the modem as that involves
the Qualcomm IP Accelerator (IPA) integration with MHI endpoint stack. But we
are planning to add support for it in the coming days.
References
==========
MHI bus: https://www.kernel.org/doc/html/latest/mhi/mhi.html
Linaro connect presentation around this topic: https://connect.linaro.org/resources/lvc21f/lvc21f-222/
Thanks,
Mani
[1] https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/tree/drivers/bus/mhi
[2] https://git.linaro.org/landing-teams/working/qualcomm/kernel.git/log/?h=tracking-qcomlt-sdx55-drivers
Changes in v2:
v2 mostly addresses the issues seen while testing the stack on SM8450 that is a
SMP platform and also incorporates the review comments from Alex.
Major changes are:
* Added a cleanup patch for getting rid of SHIFT macros and used the bitfield
operations.
* Added the endianess patches that were submitted to MHI list and used the
endianess conversion in EP patches also.
* Added support for multiple event rings.
* Fixed the MSI generation based on the event ring index.
* Fixed the doorbell list handling by making use of list splice and not locking
the entire list manipulation.
* Added new APIs for wrapping the reading and writing to host memory (Dmitry).
* Optimized the read_channel and queue_skb function logics.
* Added Hemant's R-o-b tag.
Manivannan Sadhasivam (21):
bus: mhi: Move host MHI code to "host" directory
bus: mhi: Move common MHI definitions out of host directory
bus: mhi: Make mhi_state_str[] array static inline and move to
common.h
bus: mhi: Cleanup the register definitions used in headers
bus: mhi: Get rid of SHIFT macros and use bitfield operations
bus: mhi: ep: Add support for registering MHI endpoint controllers
bus: mhi: ep: Add support for registering MHI endpoint client drivers
bus: mhi: ep: Add support for creating and destroying MHI EP devices
bus: mhi: ep: Add support for managing MMIO registers
bus: mhi: ep: Add support for ring management
bus: mhi: ep: Add support for sending events to the host
bus: mhi: ep: Add support for managing MHI state machine
bus: mhi: ep: Add support for processing MHI endpoint interrupts
bus: mhi: ep: Add support for powering up the MHI endpoint stack
bus: mhi: ep: Add support for powering down the MHI endpoint stack
bus: mhi: ep: Add support for handling MHI_RESET
bus: mhi: ep: Add support for handling SYS_ERR condition
bus: mhi: ep: Add support for processing command and TRE rings
bus: mhi: ep: Add support for queueing SKBs over MHI bus
bus: mhi: ep: Add support for suspending and resuming channels
bus: mhi: ep: Add uevent support for module autoloading
Paul Davey (2):
bus: mhi: Fix pm_state conversion to string
bus: mhi: Fix MHI DMA structure endianness
drivers/bus/Makefile | 2 +-
drivers/bus/mhi/Kconfig | 28 +-
drivers/bus/mhi/Makefile | 9 +-
drivers/bus/mhi/common.h | 319 ++++
drivers/bus/mhi/ep/Kconfig | 10 +
drivers/bus/mhi/ep/Makefile | 2 +
drivers/bus/mhi/ep/internal.h | 254 ++++
drivers/bus/mhi/ep/main.c | 1602 +++++++++++++++++++++
drivers/bus/mhi/ep/mmio.c | 274 ++++
drivers/bus/mhi/ep/ring.c | 267 ++++
drivers/bus/mhi/ep/sm.c | 174 +++
drivers/bus/mhi/host/Kconfig | 31 +
drivers/bus/mhi/{core => host}/Makefile | 4 +-
drivers/bus/mhi/{core => host}/boot.c | 17 +-
drivers/bus/mhi/{core => host}/debugfs.c | 40 +-
drivers/bus/mhi/{core => host}/init.c | 124 +-
drivers/bus/mhi/{core => host}/internal.h | 427 +-----
drivers/bus/mhi/{core => host}/main.c | 46 +-
drivers/bus/mhi/{ => host}/pci_generic.c | 0
drivers/bus/mhi/{core => host}/pm.c | 36 +-
include/linux/mhi_ep.h | 293 ++++
include/linux/mod_devicetable.h | 2 +
scripts/mod/file2alias.c | 10 +
23 files changed, 3443 insertions(+), 528 deletions(-)
create mode 100644 drivers/bus/mhi/common.h
create mode 100644 drivers/bus/mhi/ep/Kconfig
create mode 100644 drivers/bus/mhi/ep/Makefile
create mode 100644 drivers/bus/mhi/ep/internal.h
create mode 100644 drivers/bus/mhi/ep/main.c
create mode 100644 drivers/bus/mhi/ep/mmio.c
create mode 100644 drivers/bus/mhi/ep/ring.c
create mode 100644 drivers/bus/mhi/ep/sm.c
create mode 100644 drivers/bus/mhi/host/Kconfig
rename drivers/bus/mhi/{core => host}/Makefile (54%)
rename drivers/bus/mhi/{core => host}/boot.c (96%)
rename drivers/bus/mhi/{core => host}/debugfs.c (90%)
rename drivers/bus/mhi/{core => host}/init.c (93%)
rename drivers/bus/mhi/{core => host}/internal.h (50%)
rename drivers/bus/mhi/{core => host}/main.c (98%)
rename drivers/bus/mhi/{ => host}/pci_generic.c (100%)
rename drivers/bus/mhi/{core => host}/pm.c (97%)
create mode 100644 include/linux/mhi_ep.h
--
2.25.1
From: Paul Davey <[email protected]>
On big endian architectures the mhi debugfs files which report pm state
give "Invalid State" for all states. This is caused by using
find_last_bit which takes an unsigned long* while the state is passed in
as an enum mhi_pm_state which will be of int size.
Fix by using __fls to pass the value of state instead of find_last_bit.
Fixes: a6e2e3522f29 ("bus: mhi: core: Add support for PM state transitions")
Signed-off-by: Paul Davey <[email protected]>
Reviewed-by: Manivannan Sadhasivam <[email protected]>
Reviewed-by: Hemant Kumar <[email protected]>
Cc: [email protected]
Signed-off-by: Manivannan Sadhasivam <[email protected]>
---
drivers/bus/mhi/core/init.c | 9 +++++----
1 file changed, 5 insertions(+), 4 deletions(-)
diff --git a/drivers/bus/mhi/core/init.c b/drivers/bus/mhi/core/init.c
index 046f407dc5d6..0d588b60929e 100644
--- a/drivers/bus/mhi/core/init.c
+++ b/drivers/bus/mhi/core/init.c
@@ -79,10 +79,12 @@ static const char * const mhi_pm_state_str[] = {
const char *to_mhi_pm_state_str(enum mhi_pm_state state)
{
- unsigned long pm_state = state;
- int index = find_last_bit(&pm_state, 32);
+ int index;
- if (index >= ARRAY_SIZE(mhi_pm_state_str))
+ if (state)
+ index = __fls(state);
+
+ if (!state || index >= ARRAY_SIZE(mhi_pm_state_str))
return "Invalid State";
return mhi_pm_state_str[index];
@@ -789,7 +791,6 @@ static int parse_ch_cfg(struct mhi_controller *mhi_cntrl,
mhi_chan->offload_ch = ch_cfg->offload_channel;
mhi_chan->db_cfg.reset_req = ch_cfg->doorbell_mode_switch;
mhi_chan->pre_alloc = ch_cfg->auto_queue;
- mhi_chan->wake_capable = ch_cfg->wake_capable;
/*
* If MHI host allocates buffers, then the channel direction
--
2.25.1
On Wed, Feb 09, 2022 at 03:15:39PM +0530, Manivannan Sadhasivam wrote:
> From: Paul Davey <[email protected]>
>
> On big endian architectures the mhi debugfs files which report pm state
> give "Invalid State" for all states. This is caused by using
> find_last_bit which takes an unsigned long* while the state is passed in
> as an enum mhi_pm_state which will be of int size.
>
> Fix by using __fls to pass the value of state instead of find_last_bit.
>
> Fixes: a6e2e3522f29 ("bus: mhi: core: Add support for PM state transitions")
> Signed-off-by: Paul Davey <[email protected]>
> Reviewed-by: Manivannan Sadhasivam <[email protected]>
> Reviewed-by: Hemant Kumar <[email protected]>
> Cc: [email protected]
> Signed-off-by: Manivannan Sadhasivam <[email protected]>
Please ignore this patch. It is missing the v2 prefix.
Thanks,
Mani
> ---
> drivers/bus/mhi/core/init.c | 9 +++++----
> 1 file changed, 5 insertions(+), 4 deletions(-)
>
> diff --git a/drivers/bus/mhi/core/init.c b/drivers/bus/mhi/core/init.c
> index 046f407dc5d6..0d588b60929e 100644
> --- a/drivers/bus/mhi/core/init.c
> +++ b/drivers/bus/mhi/core/init.c
> @@ -79,10 +79,12 @@ static const char * const mhi_pm_state_str[] = {
>
> const char *to_mhi_pm_state_str(enum mhi_pm_state state)
> {
> - unsigned long pm_state = state;
> - int index = find_last_bit(&pm_state, 32);
> + int index;
>
> - if (index >= ARRAY_SIZE(mhi_pm_state_str))
> + if (state)
> + index = __fls(state);
> +
> + if (!state || index >= ARRAY_SIZE(mhi_pm_state_str))
> return "Invalid State";
>
> return mhi_pm_state_str[index];
> @@ -789,7 +791,6 @@ static int parse_ch_cfg(struct mhi_controller *mhi_cntrl,
> mhi_chan->offload_ch = ch_cfg->offload_channel;
> mhi_chan->db_cfg.reset_req = ch_cfg->doorbell_mode_switch;
> mhi_chan->pre_alloc = ch_cfg->auto_queue;
> - mhi_chan->wake_capable = ch_cfg->wake_capable;
>
> /*
> * If MHI host allocates buffers, then the channel direction
> --
> 2.25.1
>
On Wed, Feb 09, 2022 at 03:15:38PM +0530, Manivannan Sadhasivam wrote:
> Hello,
>
> This series adds initial support for the Qualcomm specific Modem Host Interface
> (MHI) bus in endpoint devices like SDX55 modems. The MHI bus in endpoint devices
> communicates with the MHI bus in host machines like x86 over any physical bus
> like PCIe. The MHI host support is already in mainline [1] and been used by PCIe
> based modems and WLAN devices running vendor code (downstream).
>
> Overview
> ========
>
> This series aims at adding the MHI support in the endpoint devices with the goal
> of getting data connectivity using the mainline kernel running on the modems.
> Modems here refer to the combination of an APPS processor (Cortex A grade) and
> a baseband processor (DSP). The MHI bus is located in the APPS processor and it
> transfers data packets from the baseband processor to the host machine.
>
> The MHI Endpoint (MHI EP) stack proposed here is inspired by the downstream
> code written by Qualcomm. But the complete stack is mostly re-written to adapt
> to the "bus" framework and made it modular so that it can work with the upstream
> subsystems like "PCI Endpoint". The code structure of the MHI endpoint stack
> follows the MHI host stack to maintain uniformity.
>
> With this initial MHI EP stack (along with few other drivers), we can establish
> the network interface between host and endpoint over the MHI software channels
> (IP_SW0) and can do things like IP forwarding, SSH, etc...
>
> Stack Organization
> ==================
>
> The MHI EP stack has the concept of controller and device drivers as like the
> MHI host stack. The MHI EP controller driver can be a PCI Endpoint Function
> driver and the MHI device driver can be a MHI EP Networking driver or QRTR
> driver. The MHI EP controller driver is tied to the PCI Endpoint subsystem and
> handles all bus related activities like mapping the host memory, raising IRQ,
> passing link specific events etc... The MHI EP networking driver is tied to the
> Networking stack and handles all networking related activities like
> sending/receiving the SKBs from netdev, statistics collection etc...
>
> This series only contains the MHI EP code, whereas the PCIe EPF driver and MHI
> EP Networking drivers are not yet submitted and can be found here [2]. Though
> the MHI EP stack doesn't have the build time dependency, it cannot function
> without them.
>
> Test setup
> ==========
>
> This series has been tested on Telit FN980 TLB board powered by Qualcomm SDX55
> (a.k.a X55 modem) and Qualcomm SM8450 based dev board.
>
> For testing the stability and performance, networking tools such as iperf, ssh
> and ping are used.
>
> Limitations
> ===========
>
> We are not _yet_ there to get the data packets from the modem as that involves
> the Qualcomm IP Accelerator (IPA) integration with MHI endpoint stack. But we
> are planning to add support for it in the coming days.
>
> References
> ==========
>
> MHI bus: https://www.kernel.org/doc/html/latest/mhi/mhi.html
> Linaro connect presentation around this topic: https://connect.linaro.org/resources/lvc21f/lvc21f-222/
>
> Thanks,
> Mani
>
Please ignore this patch. It is missing the v2 prefix.
Thanks,
Mani
> [1] https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/tree/drivers/bus/mhi
> [2] https://git.linaro.org/landing-teams/working/qualcomm/kernel.git/log/?h=tracking-qcomlt-sdx55-drivers
>
> Changes in v2:
>
> v2 mostly addresses the issues seen while testing the stack on SM8450 that is a
> SMP platform and also incorporates the review comments from Alex.
>
> Major changes are:
>
> * Added a cleanup patch for getting rid of SHIFT macros and used the bitfield
> operations.
> * Added the endianess patches that were submitted to MHI list and used the
> endianess conversion in EP patches also.
> * Added support for multiple event rings.
> * Fixed the MSI generation based on the event ring index.
> * Fixed the doorbell list handling by making use of list splice and not locking
> the entire list manipulation.
> * Added new APIs for wrapping the reading and writing to host memory (Dmitry).
> * Optimized the read_channel and queue_skb function logics.
> * Added Hemant's R-o-b tag.
>
> Manivannan Sadhasivam (21):
> bus: mhi: Move host MHI code to "host" directory
> bus: mhi: Move common MHI definitions out of host directory
> bus: mhi: Make mhi_state_str[] array static inline and move to
> common.h
> bus: mhi: Cleanup the register definitions used in headers
> bus: mhi: Get rid of SHIFT macros and use bitfield operations
> bus: mhi: ep: Add support for registering MHI endpoint controllers
> bus: mhi: ep: Add support for registering MHI endpoint client drivers
> bus: mhi: ep: Add support for creating and destroying MHI EP devices
> bus: mhi: ep: Add support for managing MMIO registers
> bus: mhi: ep: Add support for ring management
> bus: mhi: ep: Add support for sending events to the host
> bus: mhi: ep: Add support for managing MHI state machine
> bus: mhi: ep: Add support for processing MHI endpoint interrupts
> bus: mhi: ep: Add support for powering up the MHI endpoint stack
> bus: mhi: ep: Add support for powering down the MHI endpoint stack
> bus: mhi: ep: Add support for handling MHI_RESET
> bus: mhi: ep: Add support for handling SYS_ERR condition
> bus: mhi: ep: Add support for processing command and TRE rings
> bus: mhi: ep: Add support for queueing SKBs over MHI bus
> bus: mhi: ep: Add support for suspending and resuming channels
> bus: mhi: ep: Add uevent support for module autoloading
>
> Paul Davey (2):
> bus: mhi: Fix pm_state conversion to string
> bus: mhi: Fix MHI DMA structure endianness
>
> drivers/bus/Makefile | 2 +-
> drivers/bus/mhi/Kconfig | 28 +-
> drivers/bus/mhi/Makefile | 9 +-
> drivers/bus/mhi/common.h | 319 ++++
> drivers/bus/mhi/ep/Kconfig | 10 +
> drivers/bus/mhi/ep/Makefile | 2 +
> drivers/bus/mhi/ep/internal.h | 254 ++++
> drivers/bus/mhi/ep/main.c | 1602 +++++++++++++++++++++
> drivers/bus/mhi/ep/mmio.c | 274 ++++
> drivers/bus/mhi/ep/ring.c | 267 ++++
> drivers/bus/mhi/ep/sm.c | 174 +++
> drivers/bus/mhi/host/Kconfig | 31 +
> drivers/bus/mhi/{core => host}/Makefile | 4 +-
> drivers/bus/mhi/{core => host}/boot.c | 17 +-
> drivers/bus/mhi/{core => host}/debugfs.c | 40 +-
> drivers/bus/mhi/{core => host}/init.c | 124 +-
> drivers/bus/mhi/{core => host}/internal.h | 427 +-----
> drivers/bus/mhi/{core => host}/main.c | 46 +-
> drivers/bus/mhi/{ => host}/pci_generic.c | 0
> drivers/bus/mhi/{core => host}/pm.c | 36 +-
> include/linux/mhi_ep.h | 293 ++++
> include/linux/mod_devicetable.h | 2 +
> scripts/mod/file2alias.c | 10 +
> 23 files changed, 3443 insertions(+), 528 deletions(-)
> create mode 100644 drivers/bus/mhi/common.h
> create mode 100644 drivers/bus/mhi/ep/Kconfig
> create mode 100644 drivers/bus/mhi/ep/Makefile
> create mode 100644 drivers/bus/mhi/ep/internal.h
> create mode 100644 drivers/bus/mhi/ep/main.c
> create mode 100644 drivers/bus/mhi/ep/mmio.c
> create mode 100644 drivers/bus/mhi/ep/ring.c
> create mode 100644 drivers/bus/mhi/ep/sm.c
> create mode 100644 drivers/bus/mhi/host/Kconfig
> rename drivers/bus/mhi/{core => host}/Makefile (54%)
> rename drivers/bus/mhi/{core => host}/boot.c (96%)
> rename drivers/bus/mhi/{core => host}/debugfs.c (90%)
> rename drivers/bus/mhi/{core => host}/init.c (93%)
> rename drivers/bus/mhi/{core => host}/internal.h (50%)
> rename drivers/bus/mhi/{core => host}/main.c (98%)
> rename drivers/bus/mhi/{ => host}/pci_generic.c (100%)
> rename drivers/bus/mhi/{core => host}/pm.c (97%)
> create mode 100644 include/linux/mhi_ep.h
>
> --
> 2.25.1
>