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 andre.przywara@arm.com --- 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,