From be5187d0a821df2171e053757c89af3059250bfb Mon Sep 17 00:00:00 2001 From: Tim Newsome Date: Wed, 17 May 2023 09:46:23 -0700 Subject: [PATCH] target/riscv: Comment that data1 might change. In case in the future I have the same idea of optimizing progbuf writes again. Change-Id: Ie383487691cceeff75e2c22f4c85fc1fe4873937 Signed-off-by: Tim Newsome --- src/target/riscv/riscv-013.c | 4 ++++ 1 file changed, 4 insertions(+) diff --git a/src/target/riscv/riscv-013.c b/src/target/riscv/riscv-013.c index de57af289..ebe4951c3 100644 --- a/src/target/riscv/riscv-013.c +++ b/src/target/riscv/riscv-013.c @@ -3987,6 +3987,10 @@ static int write_memory_progbuf(struct target *target, target_addr_t address, setup_needed = false; } else { + /* Note that data1 "might not be preserved after + * an abstract command is executed," so this + * can't be optimized by only writing data1 when + * it has changed. */ if (size > 4) riscv_batch_add_dmi_write(batch, DM_DATA1, value >> 32, false); riscv_batch_add_dmi_write(batch, DM_DATA0, value, false);