shikra: Fix SMSM host count, defer BAM IRQ trigger to DT, enable BAM-DMUX#1193
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Komal-Bajaj merged 3 commits intoMay 22, 2026
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SMEM_SMSM_SIZE_INFO (id 419) is not populated by the boot firmware on Shikra. The SMSM driver falls back to SMSM_DEFAULT_NUM_HOSTS when this segment is absent, which causes SMEM_SMSM_CPU_INTR_MASK (id 333) to be allocated with the wrong size. The upstream default of 3 allocates 8*3*4 = 96 bytes. Shikra modem firmware expects 8*5*4 = 160 bytes, matching the num_hosts=5 used by the downstream kernel. The size mismatch causes the modem to crash on boot with "smsm.c: Bad pointer from smem_alloc". Increasing the host count only results in a larger allocation, so this change is safe for existing platforms. Increase the default to 5 to match the modem firmware expectation. Signed-off-by: Vishnu Santhosh <vishnu.santhosh@oss.qualcomm.com>
The driver hardcodes IRQF_TRIGGER_HIGH when registering the BAM interrupt, which overrides the trigger type specified in the device tree. This is incorrect for platforms like Shikra where the A2 BAM requires edge-triggered interrupts. Use IRQF_TRIGGER_NONE instead, which causes the kernel to use the trigger type already configured by platform_get_irq() when it parsed the device tree interrupts property. This makes the driver platform-agnostic. Signed-off-by: Vishnu Santhosh <vishnu.santhosh@oss.qualcomm.com>
This driver provides access to modem data channels on platforms using the A2 BAM hardware, including Shikra. Signed-off-by: Vishnu Santhosh <vishnu.santhosh@oss.qualcomm.com>
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This series contains two fixes and one defconfig enablement needed for Shikra modem bring-up via BAM-DMUX.
On Shikra, SMEM_SMSM_SIZE_INFO (id 419) is not populated by boot firmware, so the SMSM driver falls back to SMSM_DEFAULT_NUM_HOSTS. The upstream default of 3 allocates a smaller SMEM_SMSM_CPU_INTR_MASK (id 333) than the modem firmware expects (num_hosts=5), causing a modem crash at boot with "smsm.c: Bad pointer from smem_alloc". Bump the default to 5 to match.
The BAM DMA driver hardcodes IRQF_TRIGGER_HIGH when registering its interrupt, silently overriding the trigger type from the device tree. Shikra's A2 BAM requires edge-triggered interrupts, so this causes missed interrupts. Switch to IRQF_TRIGGER_NONE to defer to the DT configuration, making the driver platform-agnostic.
Finally, enable CONFIG_QCOM_BAM_DMUX to bring up the WWAN modem data path on Shikra and other A2 BAM platforms.