u-boot.git/arch/riscv/lib/smp.c, branch main

riscv: Remove common.h usage

2023-10-24T20:34:45Z

We can remove common.h from most cases of the code here, and only a few places need an additional header instead. Signed-off-by: Tom Rini Reviewed-by: Rick Chen

common: Drop linux/printk.h from common header

2023-09-24T13:54:57Z

This old patch was marked as deferred. Bring it back to life, to continue towards the removal of common.h Move this out of the common header and include it only where needed. Signed-off-by: Simon Glass

dm: core: Drop ofnode_is_available()

2022-09-29T20:11:31Z

This function is also available as ofnode_is_enabled(), so use that instead. Signed-off-by: Simon Glass

riscv: Introduce AVAILABLE_HARTS

2022-09-26T06:29:13Z

In SMP all harts will register themself in available_hart during start up. Then main hart will send IPI to other harts according to this variables. But this mechanism may not guarantee that all other harts can jump to next stage. When main hart is sending IPI to other hart according to available_harts, but other harts maybe still not finish the registration. Then the SMP booting will miss some harts finally. So let it become an option and it will be enabled by default. Please refer to the discussion: https://www.mail-archive.com/u-boot@lists.denx.de/msg449997.html Signed-off-by: Rick Chen Reviewed-by: Leo Yu-Chi Liang

spl: introduce SPL_XIP to config

2022-09-26T06:28:43Z

U-Boot and SPL don't necessary share the same location, so we might end with U-Boot SPL in read-only memory (XIP) and U-Boot in read-write memory. In case of non XIP boot mode, we rely on such variables as "hart_lottery" and "available_harts_lock" which we use as atomics. The problem is that CONFIG_XIP also propagate to main U-Boot, not only SPL, so we need CONFIG_SPL_XIP to distinguish SPL XIP from other XIP modes. This adds an option special for SPL to behave it in XIP manner and we don't use hart_lottery and available_harts_lock, during start proccess. Signed-off-by: Nikita Shubin Reviewed-by: Rick Chen

common: Drop asm/global_data.h from common header

2021-02-02T20:33:42Z

Move this out of the common header and include it only where needed. In a number of cases this requires adding "struct udevice;" to avoid adding another large header or in other cases replacing / adding missing header files that had been pulled in, very indirectly. Finally, we have a few cases where we did not need to include at all, so remove that include. Signed-off-by: Simon Glass Signed-off-by: Tom Rini

riscv: Use a valid bit to ignore already-pending IPIs

2020-09-30T00:54:52Z

Some IPIs may already be pending when U-Boot is started. This could be a problem if a secondary hart tries to handle an IPI before the boot hart has initialized the IPI device. To be specific, the Kendryte K210 ROM-based bootloader does not clear IPIs before passing control to U-Boot. Without this patch, the secondary hart jumps to address 0x0 as soon as it enters secondary_hart_loop, and then hangs in its trap handler. This commit introduces a valid bit so secondary harts know when and IPI originates from U-Boot, and it is safe to use the IPI API. The valid bit is initialized to 0 by board_init_f_init_reserve. Before this, secondary harts wait in wait_for_gd_init. Signed-off-by: Sean Anderson Reviewed-by: Bin Meng Reviewed-by: Rick Chen Reviewed-by: Leo Liang

riscv: Match memory barriers between send_ipi_many and handle_ipi

2020-09-30T00:54:52Z

Without a matching barrier on the write side, the barrier in handle_ipi does nothing. It was entirely possible for the boot hart to write to addr, arg0, and arg1 *after* sending the IPI, because there was no barrier on the sending side. Fixes: 90ae281437 ("riscv: add option to wait for ack from secondary harts in smp functions") Signed-off-by: Sean Anderson Reviewed-by: Bin Meng Reviewed-by: Rick Chen Reviewed-by: Leo Liang

riscv: Clean up IPI initialization code

2020-07-01T07:01:22Z

The previous IPI code initialized the device whenever the first call was made to a riscv_*_ipi function. This made it difficult to determine when the IPI device was initialized. This patch introduces a new function riscv_init_ipi. It is called once during arch_cpu_init_dm. In SPL, it is called in spl_invoke_opensbi. Before this point, no riscv_*_ipi functions should be called. Signed-off-by: Sean Anderson Reviewed-by: Rick Chen

riscv: add option to wait for ack from secondary harts in smp functions

2019-12-10T00:23:10Z

Add a wait option to smp_call_function() to wait for the secondary harts to acknowledge the call-function request. The request is considered to be acknowledged once each secondary hart has cleared the corresponding IPI. As part of the call-function request, the secondary harts invalidate the instruction cache after clearing the IPI. This adds a delay between acknowledgment (clear IPI) and fulfillment (call function) of the request. We want to use the acknowledgment to be able to judge when the request has been completed. Remove the delay by clearing the IPI after cache invalidation and just before calling the function from the request. Signed-off-by: Lukas Auer Reviewed-by: Rick Chen Tested-by: Rick Chen Reviewed-by: Anup Patel