kernel/drivers/mailbox/mailbox-mpfs.c, branch 0x221E-v0.0.1-v6.19

mailbox: mpfs: fix copy and paste bug in probe

2025-01-18T22:04:51Z

This code accidentally checks ->ctrl_base instead of ->mbox_base so the error handling can never be triggered. Fixes: a4123ffab9ec ("mailbox: mpfs: support new, syscon based, devicetree configuration") Signed-off-by: Dan Carpenter Reviewed-by: Conor Dooley Signed-off-by: Jassi Brar

mailbox: mpfs: support new, syscon based, devicetree configuration

2024-11-24T18:54:16Z

The two previous bindings for this hardware were incorrect, as the control/status and interrupt register regions should have been described as syscons and dealt with via regmap in the driver. Add support for accessing these registers using that method now, so that the hwmon driver can be supported without using auxdev or hacks with io_remap(). Signed-off-by: Conor Dooley Signed-off-by: Jassi Brar

mailbox: Explicitly include correct DT includes

2023-09-05T15:10:58Z

The DT of_device.h and of_platform.h date back to the separate of_platform_bus_type before it as merged into the regular platform bus. As part of that merge prepping Arm DT support 13 years ago, they "temporarily" include each other. They also include platform_device.h and of.h. As a result, there's a pretty much random mix of those include files used throughout the tree. In order to detangle these headers and replace the implicit includes with struct declarations, users need to explicitly include the correct includes. Signed-off-by: Rob Herring Signed-off-by: Jassi Brar

mailbox: mpfs: check the service status in .tx_done()

2023-04-03T18:26:04Z

Services are supposed to generate an interrupt once completed, whether or not they have do so successfully. What appears to be a bug in the system controller means that interrupts are only generated for *successful* services. Currently, the status of a service is only checked in the mpfs_mbox_rx_data() once an interrupt is received. As it turns out, this is not really helpful where the potentially buggy behaviour is present, as we'll only see the status for successes where it is moot anyway. Jassi suggested moving the check to the .tx_done() callback instead. This makes sense, as the busy bit that tx_done() is polling will be lowered on completion, regardless of whether the service passed or failed. That allows us to check the status bits for all services, whether they generate an interrupt or not & pass something more informative than -EBADMSG back to the drivers implementing individual services. Suggested-by: Jassi Brar Acked-by: Jassi Brar Tested-by: Valentina Fernandez Signed-off-by: Conor Dooley

mailbox: mpfs: ditch a useless busy check

2023-04-03T18:25:52Z

mpfs_mbox_rx_data() already checks if the system controller is busy before attempting to do anything, so drop the second check before reading any data. No functional change intended. Acked-by: Jassi Brar Tested-by: Valentina Fernandez Signed-off-by: Conor Dooley

mailbox: mpfs: switch to txdone_poll

2023-04-03T18:25:46Z

The system controller on PolarFire SoC has no interrupt to signify that the TX has been completed. The interrupt instead signals that a service requested by the mailbox client has succeeded. If a service fails, there will be no interrupt delivered. Switch to polling the busy register to determine whether transmission has completed. Fixes: 83d7b1560810 ("mbox: add polarfire soc system controller mailbox") Acked-by: Jassi Brar Tested-by: Valentina Fernandez Signed-off-by: Conor Dooley

mailbox: mpfs: fix an incorrect mask width

2023-04-03T18:25:31Z

The system controller registers on PolarFire SoC are 32 bits wide, so 16 + 16 as the first input to GENMASK_ULL() gives a 33 bit wide mask. It probably should have been immediately obvious when it was pointed out during review that the width required using GENMASK_ULL() - but I scarcely knew what I was doing at the time and missed it. The mistake ends up being moot as it is a mask after all, but it is incorrect and should be fixed. No functional change intended. Acked-by: Jassi Brar Tested-by: Valentina Fernandez Signed-off-by: Conor Dooley

mailbox: mpfs: read the system controller's status

2022-12-19T02:40:30Z

Some services explicitly return an error code in their response, but others rely on the system controller to set a status in its status register. The meaning of the bits varies based on what service is requested, so pass it back up to the driver that requested the service in the first place. The field in the message struct already existed, but was unused until now. If the system controller is busy, in which case we should never actually be in the interrupt handler, or if the service fails the mailbox itself should not be read. Callers should check the status before operating on the response. There's an existing, but unused, #define for the mailbox mask - but it was incorrect. It was doing a GENMASK_ULL(32, 16) which should've just been a GENMASK(31, 16), so fix that up and start using it. Fixes: 83d7b1560810 ("mbox: add polarfire soc system controller mailbox") Signed-off-by: Conor Dooley Reviewed-by: Palmer Dabbelt Signed-off-by: Jassi Brar

mailbox: mpfs: account for mbox offsets while sending

2022-10-06T02:48:38Z

The mailbox offset is not only used for receiving messages, but it is also used by messages sent to the system controller by Linux that have a payload, such as the "digital signature service". It is also overloaded by certain other services (reprogramming of the FPGA fabric, see Link:) to have a meaning other than the offset the system controller should read from. When the driver was written, no such services of the latter type were in use & those of the former used an offset of zero so this has gone un-noticed. Link: https://www.microsemi.com/document-portal/doc_download/1245815-polarfire-fpga-and-polarfire-soc-fpga-system-services-user-guide # Section 5.2 Fixes: 83d7b1560810 ("mbox: add polarfire soc system controller mailbox") Signed-off-by: Conor Dooley Signed-off-by: Jassi Brar

mailbox: mpfs: fix handling of the reg property

2022-10-06T02:48:31Z

The "data" region of the PolarFire SoC's system controller mailbox is not one continuous register space - the system controller's QSPI sits between the control and data registers. Split the "data" reg into two parts: "data" & "control". Optionally get the "data" register address from the 3rd reg property in the devicetree & fall back to using the old base + MAILBOX_REG_OFFSET that the current code uses. Fixes: 83d7b1560810 ("mbox: add polarfire soc system controller mailbox") Signed-off-by: Conor Dooley Signed-off-by: Jassi Brar