Using memcpy() is, however tempting, not a good idea: It depends on the
specific implementation of memcpy, also lacks barriers. In this
particular case the first registers were written using 64-bit writes,
and the last register using four separate single-byte writes.

Replace the memcpy with a proper loop using the writel() accessor.

Signed-off-by: Andre Przywara <[email protected]>
---
 arch/arm/mach-sunxi/dram_sun50i_h6.c | 6 ++++--
 1 file changed, 4 insertions(+), 2 deletions(-)

diff --git a/arch/arm/mach-sunxi/dram_sun50i_h6.c 
b/arch/arm/mach-sunxi/dram_sun50i_h6.c
index 5da90a2835..e2f141eb9b 100644
--- a/arch/arm/mach-sunxi/dram_sun50i_h6.c
+++ b/arch/arm/mach-sunxi/dram_sun50i_h6.c
@@ -182,6 +182,7 @@ static void mctl_set_timing_lpddr3(struct dram_para *para)
                        (struct sunxi_mctl_ctl_reg *)SUNXI_DRAM_CTL0_BASE;
        struct sunxi_mctl_phy_reg * const mctl_phy =
                        (struct sunxi_mctl_phy_reg *)SUNXI_DRAM_PHY0_BASE;
+       int i;
 
        u8 tccd         = 2;
        u8 tfaw         = max(ns_to_t(50), 4);
@@ -237,8 +238,9 @@ static void mctl_set_timing_lpddr3(struct dram_para *para)
        u8 twr2rd       = tcwl + 4 + 1 + twtr;
        u8 trd2wr       = tcl + 4 + (tcksrea >> 1) - tcwl + 1;
 
-       /* set mode register */
-       memcpy(mctl_phy->mr, mr_lpddr3, sizeof(mr_lpddr3));
+       /* set mode registers */
+       for (i = 0; i < ARRAY_SIZE(mr_lpddr3); i++)
+               writel(mr_lpddr3[i], &mctl_phy->mr[i]);
 
        /* set DRAM timing */
        writel((twtp << 24) | (tfaw << 16) | (trasmax << 8) | tras,
-- 
2.17.1

-- 
You received this message because you are subscribed to the Google Groups 
"linux-sunxi" group.
To unsubscribe from this group and stop receiving emails from it, send an email 
to [email protected].
To view this discussion on the web, visit 
https://groups.google.com/d/msgid/linux-sunxi/20190702095148.191065-2-andre.przywara%40arm.com.
For more options, visit https://groups.google.com/d/optout.

Reply via email to