[PATCH] ptp_qoriq: use div_u64/div_u64_rem for 64-bit division

[PATCH] ptp_qoriq: use div_u64/div_u64_rem for 64-bit division

[Yangbo Lu]

This is a fix-up patch for below build issue with multi_v7_defconfig.

drivers/ptp/ptp_qoriq.o: In function `qoriq_ptp_probe':
ptp_qoriq.c:(.text+0xd0c): undefined reference to `__aeabi_uldivmod'

Fixes: 91305f281262 ("ptp_qoriq: support automatic configuration for ptp timer")
Signed-off-by: Yangbo Lu <yangbo.lu@nxp.com>
---
 drivers/ptp/ptp_qoriq.c |    6 ++++--
 1 files changed, 4 insertions(+), 2 deletions(-)

diff --git a/drivers/ptp/ptp_qoriq.c b/drivers/ptp/ptp_qoriq.c
index 095c185..fdd49c2 100644
--- a/drivers/ptp/ptp_qoriq.c
+++ b/drivers/ptp/ptp_qoriq.c
@@ -373,6 +373,7 @@ static int qoriq_ptp_auto_config(struct qoriq_ptp *qoriq_ptp,
 	u64 freq_comp;
 	u64 max_adj;
 	u32 nominal_freq;
+	u32 remainder = 0;
 	u32 clk_src = 0;
 
 	qoriq_ptp->cksel = DEFAULT_CKSEL;
@@ -400,7 +401,8 @@ static int qoriq_ptp_auto_config(struct qoriq_ptp *qoriq_ptp,
 	 * freq_ratio = reference_clock_freq / nominal_freq
 	 */
 	freq_comp = ((u64)1 << 32) * nominal_freq;
-	if (do_div(freq_comp, clk_src))
+	freq_comp = div_u64_rem(freq_comp, clk_src, &remainder);
+	if (remainder)
 		freq_comp++;
 
 	qoriq_ptp->tmr_add = freq_comp;
@@ -411,7 +413,7 @@ static int qoriq_ptp_auto_config(struct qoriq_ptp *qoriq_ptp,
 	 * freq_ratio = reference_clock_freq / nominal_freq
 	 */
 	max_adj = 1000000000ULL * (clk_src - nominal_freq);
-	max_adj = max_adj / nominal_freq - 1;
+	max_adj = div_u64(max_adj, nominal_freq) - 1;
 	qoriq_ptp->caps.max_adj = max_adj;
 
 	return 0;
-- 
1.7.1

Re: [PATCH] ptp_qoriq: use div_u64/div_u64_rem for 64-bit division

[David Miller]

From: Yangbo Lu <yangbo.lu@nxp.com>
Date: Mon,  6 Aug 2018 12:39:11 +0800

> This is a fix-up patch for below build issue with multi_v7_defconfig.
> 
> drivers/ptp/ptp_qoriq.o: In function `qoriq_ptp_probe':
> ptp_qoriq.c:(.text+0xd0c): undefined reference to `__aeabi_uldivmod'
> 
> Fixes: 91305f281262 ("ptp_qoriq: support automatic configuration for ptp timer")
> Signed-off-by: Yangbo Lu <yangbo.lu@nxp.com>

Applied.