[PATCH V4 23/23] crypto: hisilicon/qm: Workaround to enable build with RISC-V clang

Sunil V L
2023-04-04T18:26:40Z

With CONFIG_ACPI enabled for RISC-V, this driver gets enabled in
allmodconfig build. The gcc tool chain builds this driver removing the
inline arm64 assembly code. However, clang for RISC-V tries to build
the arm64 assembly and below error is seen.

drivers/crypto/hisilicon/qm.c:627:10: error: invalid output constraint '+Q' in asm
"+Q" (*((char __iomem *)fun_base))
^
It appears that RISC-V clang is not smart enough to detect
IS_ENABLED(CONFIG_ARM64) and remove the dead code.

As a workaround, move this check to preprocessing stage which works
with the RISC-V clang tool chain.

Signed-off-by: Sunil V L <sunilvl@ventanamicro.com>
---
drivers/crypto/hisilicon/qm.c | 13 +++++++------
1 file changed, 7 insertions(+), 6 deletions(-)

diff --git a/drivers/crypto/hisilicon/qm.c b/drivers/crypto/hisilicon/qm.c
index e4c84433a88a..a5f521529ab2 100644
--- a/drivers/crypto/hisilicon/qm.c
+++ b/drivers/crypto/hisilicon/qm.c
@@ -611,13 +611,9 @@ EXPORT_SYMBOL_GPL(hisi_qm_wait_mb_ready);
static void qm_mb_write(struct hisi_qm *qm, const void *src)
{
void __iomem *fun_base = qm->io_base + QM_MB_CMD_SEND_BASE;
- unsigned long tmp0 = 0, tmp1 = 0;

- if (!IS_ENABLED(CONFIG_ARM64)) {
- memcpy_toio(fun_base, src, 16);
- dma_wmb();
- return;
- }
+#if IS_ENABLED(CONFIG_ARM64)
+ unsigned long tmp0 = 0, tmp1 = 0;

asm volatile("ldp %0, %1, %3\n"
"stp %0, %1, %2\n"
@@ -627,6 +623,11 @@ static void qm_mb_write(struct hisi_qm *qm, const void *src)
"+Q" (*((char __iomem *)fun_base))
: "Q" (*((char *)src))
: "memory");
+#else
+ memcpy_toio(fun_base, src, 16);
+ dma_wmb();
+#endif
+
}

static int qm_mb_nolock(struct hisi_qm *qm, struct qm_mailbox *mailbox)
--
2.34.1