kernel/include/linux/mailbox/mtk-cmdq-mailbox.h, branch master

mailbox: mtk-cmdq: Add mminfra_offset configuration for DRAM transaction

2026-01-19T11:57:45Z

The GCE in MT8196 is placed in MMINFRA and requires all addresses in GCE instructions for DRAM transactions to be IOVA. Due to MMIO, if the GCE needs to access a hardware register at 0x1000_0000, but the SMMU is also mapping a DRAM block at 0x1000_0000, the MMINFRA will not know whether to write to the hardware register or the DRAM. To solve this, MMINFRA treats addresses greater than 2G as data paths and those less than 2G as config paths because the DRAM start address is currently at 2G (0x8000_0000). On the data path, MMINFRA remaps DRAM addresses by subtracting 2G, allowing SMMU to map DRAM addresses less than 2G. For example, if the DRAM start address 0x8000_0000 is mapped to IOVA=0x0, when GCE accesses IOVA=0x0, it must add a 2G offset to the address in the GCE instruction. MMINFRA will then see it as a data path (IOVA >= 2G) and subtract 2G, allowing GCE to access IOVA=0x0. Since the MMINFRA remap subtracting 2G is done in hardware and cannot be configured by software, the address of DRAM in GCE instruction must always add 2G to ensure proper access. After that, the shift functions do more than just shift addresses, so the APIs were renamed to cmdq_convert_gce_addr() and cmdq_revert_gce_addr(). This 2G adjustment is referred to as mminfra_offset in the CMDQ driver. CMDQ helper can get the mminfra_offset from the cmdq_mbox_priv of cmdq_pkt and add the mminfra_offset to the DRAM address in GCE instructions. Signed-off-by: Jason-JH Lin Reviewed-by: AngeloGioacchino Del Regno Acked-by: Jassi Brar Acked-by: AngeloGioacchino Del Regno Signed-off-by: AngeloGioacchino Del Regno

mailbox: mtk-cmdq: Add cmdq private data to cmdq_pkt for generating instruction

2026-01-19T11:57:44Z

Add the cmdq_mbox_priv structure to store the private data of GCE, such as the shift bits of the physical address. Then, include the cmdq_mbox_priv structure within the cmdq_pkt structure. This allows CMDQ users to utilize the private data in cmdq_pkt to generate GCE instructions when needed. Additionally, having cmdq_mbox_priv makes it easier to expand and reference other GCE private data in the future. Add cmdq_get_mbox_priv() for CMDQ users to get all the private data into the cmdq_mbox_priv of the cmdq_pkt. Signed-off-by: Jason-JH Lin Reviewed-by: AngeloGioacchino Del Regno Acked-by: Jassi Brar Acked-by: AngeloGioacchino Del Regno Signed-off-by: AngeloGioacchino Del Regno

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

2025-11-28T15:31:53Z

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

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: 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

soc: mediatek: cmdq: add clear option in cmdq_pkt_wfe api

2020-09-25T15:27:39Z

Add clear parameter to let client decide if event should be clear to 0 after GCE receive it. Signed-off-by: Dennis YC Hsieh Acked-by: Chun-Kuang Hu Link: https://lore.kernel.org/r/1594136714-11650-9-git-send-email-dennis-yc.hsieh@mediatek.com [mb: fix commit message] Signed-off-by: Matthias Brugger

soc: mediatek: cmdq: add read_s function

2020-09-25T15:27:34Z

Add read_s function in cmdq helper functions which support read value from register or dma physical address into gce internal register. Signed-off-by: Dennis YC Hsieh Link: https://lore.kernel.org/r/1594136714-11650-5-git-send-email-dennis-yc.hsieh@mediatek.com Signed-off-by: Matthias Brugger

soc: mediatek: cmdq: add write_s_mask function

2020-09-25T15:27:32Z

add write_s_mask function in cmdq helper functions which writes value contains in internal register to address with mask and large dma access support. Signed-off-by: Dennis YC Hsieh Link: https://lore.kernel.org/r/1594136714-11650-4-git-send-email-dennis-yc.hsieh@mediatek.com Signed-off-by: Matthias Brugger