kernel/include/linux/mailbox, branch linux-6.17.y

mailbox: mtk-cmdq: Refine DMA address handling for the command buffer

2025-12-06T21:27:33Z

[ Upstream commit a195c7ccfb7a21b8118139835e25936ec8722596 ] GCE can only fetch the command buffer address from a 32-bit register. Some SoCs support a 35-bit command buffer address for GCE, which requires a right shift of 3 bits before setting the address into the 32-bit register. A comment has been added to the header of cmdq_get_shift_pa() to explain this requirement. To prevent the GCE command buffer address from being DMA mapped beyond its supported bit range, the DMA bit mask for the device is set during initialization. Additionally, to ensure the correct shift is applied when setting or reading the register that stores the GCE command buffer address, new APIs, cmdq_convert_gce_addr() and cmdq_revert_gce_addr(), have been introduced for consistent operations on this register. The variable type for the command buffer address has been standardized to dma_addr_t to prevent handling issues caused by type mismatches. Fixes: 0858fde496f8 ("mailbox: cmdq: variablize address shift in platform") Signed-off-by: Jason-JH Lin Reviewed-by: AngeloGioacchino Del Regno Signed-off-by: Jassi Brar Signed-off-by: Sasha Levin

mailbox: mtk-cmdq: remove cl in struct cmdq_pkt

2025-03-27T01:58:24Z

Every client driver has the struct cmdq_client information, so it's not necessary to store it in struct cmdq_pkt. cl is used to store struct cmdq_client information and now no client driver use it, so remove it. Signed-off-by: Chun-Kuang Hu Signed-off-by: Jassi Brar

mailbox: add Samsung Exynos driver

2025-01-18T22:18:48Z

The Samsung Exynos mailbox controller, used on Google GS101 SoC, has 16 flag bits for hardware interrupt generation and a shared register for passing mailbox messages. When the controller is used by the ACPM interface the shared register is ignored and the mailbox controller acts as a doorbell. The controller just raises the interrupt to APM after the ACPM interface has written the message to SRAM. Add support for the Samsung Exynos mailbox controller. Signed-off-by: Tudor Ambarus Signed-off-by: Jassi Brar

mailbox: add Microchip IPC support

2025-01-18T22:09:48Z

Add a mailbox controller driver for the Microchip Inter-processor Communication (IPC), which is used to send and receive data between processors. The driver uses the RISC-V Supervisor Binary Interface (SBI) to communicate with software running in machine mode (M-mode) to access the IPC hardware block. Additional details on the Microchip vendor extension and the IPC function IDs described in the driver can be found in the following documentation: https://github.com/linux4microchip/microchip-sbi-ecall-extension This SBI interface in this driver is compatible with the Mi-V Inter-hart Communication (IHC) IP. Transmitting and receiving data through the mailbox framework is done through struct mchp_ipc_msg. Signed-off-by: Valentina Fernandez Signed-off-by: Jassi Brar

mailbox: zynqmp: Fix typo in IPI documentation

2023-03-14T19:28:12Z

Xilinx IPI message buffers allows 32-byte data transfer. Fix documentation that says 12 bytes Fixes: 4981b82ba2ff ("mailbox: ZynqMP IPI mailbox controller") Signed-off-by: Tanmay Shah Acked-by: Michal Simek Cc: stable@vger.kernel.org Link: https://lore.kernel.org/r/20230311012407.1292118-4-tanmay.shah@amd.com Signed-off-by: Mathieu Poirier

mailbox: mtk-cmdq: Remove proprietary cmdq_task_cb

2022-08-02T20:06:57Z

rx_callback is a standard mailbox callback mechanism and could cover the function of proprietary cmdq_task_cb, so use the standard one instead of the proprietary one. Client driver has changed to use standard rx_callback, so remove proprietary cmdq_task_cb. Signed-off-by: Chun-Kuang Hu Reviewed-by: Matthias Brugger Signed-off-by: Jassi Brar

mailbox: mtk-cmdq: Add struct cmdq_pkt in struct cmdq_cb_data

2021-06-26T16:40:20Z

Current client use 'struct cmdq_pkt' as callback data, so change 'void *data' to 'struct cmdq_pkt *pkt'. Keep data until client use pkt instead of data. Signed-off-by: Chun-Kuang Hu Reviewed-by: Yongqiang Niu Signed-off-by: Jassi Brar

mailbox: mtk-cmdq: Remove cmdq_cb_status

2021-06-26T16:39:54Z

cmdq_cb_status is an error status. Use the standard error number instead of cmdq_cb_status to prevent status duplication. Signed-off-by: Chun-Kuang Hu Reviewed-by: Yongqiang Niu Signed-off-by: Jassi Brar

mailbox: arm_mhuv2: Add driver

2020-12-10T01:26:02Z

This adds driver for the ARM MHUv2 (Message Handling Unit) mailbox controller. This is based on the accepted DT bindings of the controller and supports combination of both transport protocols, i.e. doorbell and data-transfer. Transmitting and receiving data through the mailbox framework is done through struct arm_mhuv2_mbox_msg. Based on the initial work done by Morten Borup Petersen from ARM. Co-developed-by: Tushar Khandelwal Signed-off-by: Tushar Khandelwal Tested-by: Usama Arif Signed-off-by: Viresh Kumar Signed-off-by: Jassi Brar

mailbox: zynqmp-ipi-message: Replace zero-length array with flexible-array member

2020-10-29T22:22:59Z

There is a regular need in the kernel to provide a way to declare having a dynamically sized set of trailing elements in a structure. Kernel code should always use “flexible array members”[1] for these cases. The older style of one-element or zero-length arrays should no longer be used[2]. [1] https://en.wikipedia.org/wiki/Flexible_array_member [2] https://www.kernel.org/doc/html/v5.9-rc1/process/deprecated.html#zero-length-and-one-element-arrays Signed-off-by: Gustavo A. R. Silva