From a20a02e82af541fa1e2fd34b73d42d3f2c2d9c1e Mon Sep 17 00:00:00 2001 From: Nico Huber Date: Sun, 28 Mar 2021 18:27:08 +0200 Subject: [PATCH] nb/intel/x4x: Refactor sync DLL programming (part 1) Extract some common code patterns into functions. Change-Id: I5f8d40bb55d4b4f0639e0287881ae0ecde298590 Signed-off-by: Nico Huber Reviewed-on: https://review.coreboot.org/c/coreboot/+/51905 Tested-by: build bot (Jenkins) Reviewed-by: Arthur Heymans Reviewed-by: Angel Pons --- src/northbridge/intel/x4x/raminit_ddr23.c | 62 ++++++++++++----------- 1 file changed, 32 insertions(+), 30 deletions(-) diff --git a/src/northbridge/intel/x4x/raminit_ddr23.c b/src/northbridge/intel/x4x/raminit_ddr23.c index b3321d5bf2..99c07f5970 100644 --- a/src/northbridge/intel/x4x/raminit_ddr23.c +++ b/src/northbridge/intel/x4x/raminit_ddr23.c @@ -663,6 +663,30 @@ static void program_timings(struct sysinfo *s) mchbar_clrsetbits8(0x6c4, 0x7, 0x2); } +const unsigned int sync_dll_max_taps = 16; + +static void sync_dll_load_tap(unsigned int tap) +{ + mchbar_clrsetbits8(0x1c8, 0x1f, tap & 0x1f); + mchbar_setbits8(0x180, 1 << 4); + do {} while (mchbar_read8(0x180) & (1 << 4)); +} + +static bool sync_dll_test_tap(unsigned int tap, uint32_t val) +{ + if (tap >= sync_dll_max_taps) + return false; + sync_dll_load_tap(tap); + return mchbar_read32(0x184) == val; +} + +static void sync_dll_search_tap(uint8_t *tap, uint32_t val) +{ + for (; *tap < sync_dll_max_taps; ++*tap) + if (sync_dll_test_tap(*tap, val)) + return; +} + static void program_dll(struct sysinfo *s) { u8 i, j, r, reg8, clk, async = 0; @@ -821,12 +845,8 @@ static void program_dll(struct sysinfo *s) mchbar_clrbits16(0x180, 1 << 15 | 1 << 9); mchbar_setbits8(0x180, 1 << 2); j = 0; - for (i = 0; i < 16; i++) { - mchbar_clrsetbits8(0x1c8, 0x1f, i); - mchbar_setbits8(0x180, 1 << 4); - while (mchbar_read8(0x180) & (1 << 4)) - ; - if (mchbar_read32(0x184) == 0xffffffff) { + for (i = 0; i < sync_dll_max_taps; i++) { + if (sync_dll_test_tap(i, 0xffffffff)) { j++; if (j >= 2) break; @@ -842,22 +862,10 @@ static void program_dll(struct sysinfo *s) if (i == 1 || ((i == 0) && s->selected_timings.mem_clk == MEM_CLOCK_667MHz)) { j = 0; i++; - for (; i < 16; i++) { - mchbar_clrsetbits8(0x1c8, 0x1f, i); - mchbar_setbits8(0x180, 1 << 4); - while (mchbar_read8(0x180) & (1 << 4)) - ; - if (mchbar_read32(0x184) == 0) { - i++; - break; - } - } - for (; i < 16; i++) { - mchbar_clrsetbits8(0x1c8, 0x1f, i); - mchbar_setbits8(0x180, 1 << 4); - while (mchbar_read8(0x180) & (1 << 4)) - ; - if (mchbar_read32(0x184) == 0xffffffff) { + sync_dll_search_tap(&i, 0); + i++; + for (; i < sync_dll_max_taps; i++) { + if (sync_dll_test_tap(i, 0xffffffff)) { j++; if (j >= 2) break; @@ -866,10 +874,7 @@ static void program_dll(struct sysinfo *s) } } if (j < 2) { - mchbar_clrsetbits8(0x1c8, 0x1f, 0); - mchbar_setbits8(0x180, 1 << 4); - while (mchbar_read8(0x180) & (1 << 4)) - ; + sync_dll_load_tap(0); j = 2; } } @@ -890,10 +895,7 @@ static void program_dll(struct sysinfo *s) i = (i + 10) % 14; else /* DDR3 */ i = (i + 3) % 12; - mchbar_clrsetbits8(0x1c8, 0x1f, i); - mchbar_setbits8(0x180, 1 << 4); - while (mchbar_read8(0x180) & (1 << 4)) - ; + sync_dll_load_tap(i); } switch (s->selected_timings.mem_clk) {