opensbi.git/lib/utils/irqchip, branch v1.7

lib: sbi: Use sbi_hart_count() and sbi_for_each_hartindex()

2025-03-24T12:27:20Z

Simplify the code and improve consistency by using the new macros where possible. sbi_hart_count() obsoletes sbi_scratch_last_hartindex(). Signed-off-by: Samuel Holland Reviewed-by: Anup Patel

Revert "lib: utils/irqchip: Match against more specific compatible strings first"

2025-03-24T11:07:52Z

This reverts commit 6019259dfbdf9322858b4e7cfc3d1448376e2aa0. Now that fdt_driver_init_by_offset() respects the compatible string fallback priority order, this workaround is no longer necessary. Signed-off-by: Samuel Holland Reviewed-by: Anup Patel

lib: utils/irqchip: Match against more specific compatible strings first

2025-02-19T16:19:08Z

The T-HEAD C90x PLIC has some special quirks, such as the S-mode delegation bit. OpenSBI currently handles this by checking the compatible string in the device tree. However, this matching is done in the order of the fdt_match array. So if a device tree contains both strings, for example: compatible = "thead,c900-plic", "riscv,plic0"; Then OpenSBI will match against the generic "riscv,plic0" string, since that appears first in the fdt_match array. This means it will fail to set the S-mode delegation bit, and Linux will fail to boot. In some cases, it is not possible to change the compatible string to just the T-HEAD PLIC, as older versions of Linux only recognize the RISC-V compatible string. This patch fixes that by moving the RISC-V string to the end, ensuring that the more specific options get matched first. Signed-off-by: Alex Studer Reviewed-by: Anup Patel

lib: utils/irqchip: Use fdt_driver for initialization

2025-02-12T15:52:37Z

The irqchip driver subsystem does not need any extra data, so it can use `struct fdt_driver` directly. The generic fdt_irqchip_init() performs a best-effort initialization of all matching DT nodes. Signed-off-by: Samuel Holland Reviewed-by: Anup Patel

lib: utils: Fix irqchip registration for PLIC and APLIC

2024-12-24T08:36:09Z

Currently, the same irqchip instance is registered for multiple PLIC and APLIC instances which causes the sbi_list_for_each_entry() loop in the sbi_irqchip_init() to hang at boot-time. To address the above issue, register a separate irqchip instance for each PLIC and APLIC instance. Fixes: 2dd6eaf68055 ("lib: sbi_irqchip: Call driver warm_init from SBI core") Reported-by: Himanshu Chauhan Signed-off-by: Anup Patel Reviewed-by: Himanshu Chauhan

treewide: Make carray arrays const and NULL-terminated

2024-11-28T11:39:17Z

This allows the compiler to generate significantly better code, because it does not have to maintain either the loop counter or loop limit. Plus there are half as many symbols to relocate. This also simplifies passing carray arrays to helper functions. Signed-off-by: Samuel Holland Reviewed-by: Anup Patel

lib: sbi_irqchip: Set the IRQ handler when registering a chip

2024-11-28T06:21:56Z

In addition to saving some code size, this moves the decision about setting the top-level external interrupt handler to the irqchip core, not the specific driver, which would be needed to support chained interrupt handlers. Signed-off-by: Samuel Holland Reviewed-by: Anup Patel

platform: Drop irqchip warm init and exit hooks

2024-11-28T06:16:36Z

Now that driver lifecycle is managed from within the SBI irqchip core, platforms need only to initialize the driver once during cold init. Remove the remaining platform hooks that are no longer used. Signed-off-by: Samuel Holland Reviewed-by: Anup Patel

lib: sbi_irqchip: Call driver warm_init from SBI core

2024-11-28T06:10:17Z

Currently, each platform keeps track of which irqchip driver is in use and calls its warm init function. Since the generic platform may use multiple irqchip drivers, it has logic to track an array of drivers. The code is simplified and made common across platforms by treating warm init and exit as properties of the driver, not the platform. Then the platform's only role is to select and prepare a driver during cold boot. For now, only add a .warm_init hook, since none of the existing drivers need an .exit hook. It could be added in the future if needed. Signed-off-by: Samuel Holland Reviewed-by: Anup Patel

lib: sbi_irqchip: Register devices during cold init

2024-11-28T06:07:25Z

Have the SBI irqchip core keep track of registered irqchip devices. This is useful for any callbacks the irqchip driver may have, such as for warm initialization, the external interrupt handler function, and any future support for handling external interrupts (beyond IPIs) in M-mode. This improves on the tracking done in fdt_irqchip.c, as it tracks device instances, not just drivers, so callbacks can target a specific device. Signed-off-by: Samuel Holland Reviewed-by: Anup Patel