From 7048bb13b2d6309ef8386fca665247d3afa36ab0 Mon Sep 17 00:00:00 2001 From: Lars Povlsen Date: Thu, 6 Feb 2020 10:45:40 +0100 Subject: mips: vcoreiii: Fix cache coherency issues This patch fixes an stability issue seen on some vcoreiii targets, which was root caused to a cache inconsistency situation. The inconsistency was caused by having kuseg pointing to NOR area but used as a stack/gd/heap area during initialization, while only relatively late remapping the RAM area into kuseg position. The fix is to initialize the DDR right after the TLB setup, and then remapping it into position before gd/stack/heap usage. Reported-by: Ramin Seyed-Moussavi Reviewed-by: Alexandre Belloni Reviewed-by: Horatiu Vultur Signed-off-by: Lars Povlsen --- arch/mips/mach-mscc/lowlevel_init.S | 17 ++++++++++++++++- 1 file changed, 16 insertions(+), 1 deletion(-) (limited to 'arch/mips/mach-mscc/lowlevel_init.S') diff --git a/arch/mips/mach-mscc/lowlevel_init.S b/arch/mips/mach-mscc/lowlevel_init.S index dfbe06766c..91f29ae252 100644 --- a/arch/mips/mach-mscc/lowlevel_init.S +++ b/arch/mips/mach-mscc/lowlevel_init.S @@ -8,6 +8,7 @@ .set noreorder .extern vcoreiii_tlb_init + .extern vcoreiii_ddr_init #ifdef CONFIG_SOC_LUTON .extern pll_init #endif @@ -17,14 +18,28 @@ LEAF(lowlevel_init) * As we have no stack yet, we can assume the restricted * luxury of the sX-registers without saving them */ - move s0,ra + + /* Modify ra/s0 such we return to physical NOR location */ + li t0, 0x0fffffff + li t1, CONFIG_SYS_TEXT_BASE + and s0, ra, t0 + add s0, s0, t1 jal vcoreiii_tlb_init nop + #ifdef CONFIG_SOC_LUTON jal pll_init nop #endif + + /* Initialize DDR controller to enable stack/gd/heap */ +0: + jal vcoreiii_ddr_init + nop + bnez v0, 0b /* Retry on error */ + nop + jr s0 nop END(lowlevel_init) -- cgit v1.2.3