From mboxrd@z Thu Jan 1 00:00:00 1970 From: Andre Przywara Date: Mon, 5 Dec 2016 01:52:14 +0000 Subject: [U-Boot] [PATCH v2 07/23] armv8: add simple sdelay implementation In-Reply-To: <1480902750-839-1-git-send-email-andre.przywara@arm.com> References: <1480902750-839-1-git-send-email-andre.przywara@arm.com> Message-ID: <1480902750-839-8-git-send-email-andre.przywara@arm.com> List-Id: MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit To: u-boot@lists.denx.de The sunxi DRAM setup code needs an sdelay() implementation, which wasn't defined for armv8 so far. Shamelessly copy the armv7 version and adjust it to work in AArch64. Signed-off-by: Andre Przywara --- arch/arm/cpu/armv8/cpu.c | 13 +++++++++++++ 1 file changed, 13 insertions(+) diff --git a/arch/arm/cpu/armv8/cpu.c b/arch/arm/cpu/armv8/cpu.c index e06c3cc..0366ff4 100644 --- a/arch/arm/cpu/armv8/cpu.c +++ b/arch/arm/cpu/armv8/cpu.c @@ -16,6 +16,19 @@ #include #include +/************************************************************ + * sdelay() - simple spin loop. Will be constant time as + * its generally used in bypass conditions only. This + * is necessary until timers are accessible. + * + * not inline to increase chances its in cache when called + *************************************************************/ +void sdelay(unsigned long loops) +{ + __asm__ volatile ("1:\n" "subs %0, %0, #1\n" + "b.ne 1b" : "=r" (loops) : "0"(loops) : "cc"); +} + int cleanup_before_linux(void) { /* -- 2.8.2