[PATCH 07/12] lib: sbi: Simplify halt broadcast logic

[Samuel Holland]

Use the IPI .update callback to exclude the local hart. This allows
reusing the normal logic for broadcasting an IPI to all active harts.

Signed-off-by: Samuel Holland <samuel.holland at sifive.com>
---

 lib/sbi/sbi_ipi.c    | 10 ++++++++++
 lib/sbi/sbi_system.c | 11 +----------
 2 files changed, 11 insertions(+), 10 deletions(-)

diff --git a/lib/sbi/sbi_ipi.c b/lib/sbi/sbi_ipi.c
index 505aafd8..0cffa0af 100644
--- a/lib/sbi/sbi_ipi.c
+++ b/lib/sbi/sbi_ipi.c
@@ -208,6 +208,15 @@ void sbi_ipi_clear_smode(void)
 	csr_clear(CSR_MIP, MIP_SSIP);
 }
 
+static int sbi_ipi_update_halt(struct sbi_scratch *scratch,
+			       struct sbi_scratch *remote_scratch,
+			       u32 remote_hartindex, void *data)
+{
+	/* Never send a halt IPI to the local hart. */
+	return scratch == remote_scratch ?
+		SBI_IPI_UPDATE_BREAK : SBI_IPI_UPDATE_SUCCESS;
+}
+
 static void sbi_ipi_process_halt(struct sbi_scratch *scratch)
 {
 	sbi_hsm_hart_stop(scratch, true);
@@ -215,6 +224,7 @@ static void sbi_ipi_process_halt(struct sbi_scratch *scratch)
 
 static struct sbi_ipi_event_ops ipi_halt_ops = {
 	.name = "IPI_HALT",
+	.update = sbi_ipi_update_halt,
 	.process = sbi_ipi_process_halt,
 };
 
diff --git a/lib/sbi/sbi_system.c b/lib/sbi/sbi_system.c
index c068b725..f3c49bbd 100644
--- a/lib/sbi/sbi_system.c
+++ b/lib/sbi/sbi_system.c
@@ -65,20 +65,11 @@ bool sbi_system_reset_supported(u32 reset_type, u32 reset_reason)
 
 void __noreturn sbi_system_reset(u32 reset_type, u32 reset_reason)
 {
-	ulong hbase = 0, hmask;
-	u32 cur_hartid = current_hartid();
 	struct sbi_domain *dom = sbi_domain_thishart_ptr();
 	struct sbi_scratch *scratch = sbi_scratch_thishart_ptr();
 
 	/* Send HALT IPI to every hart other than the current hart */
-	while (!sbi_hsm_hart_interruptible_mask(dom, hbase, &hmask)) {
-		if ((hbase <= cur_hartid)
-			  && (cur_hartid < hbase + BITS_PER_LONG))
-			hmask &= ~(1UL << (cur_hartid - hbase));
-		if (hmask)
-			sbi_ipi_send_halt(hmask, hbase);
-		hbase += BITS_PER_LONG;
-	}
+	sbi_ipi_send_halt(0, -1UL);
 
 	/* Stop current HART */
 	sbi_hsm_hart_stop(scratch, false);
-- 
2.45.1