diff options
Diffstat (limited to 'arch/arm/mach-sunxi/dram_timings/a523_ddr3.c')
| -rw-r--r-- | arch/arm/mach-sunxi/dram_timings/a523_ddr3.c | 113 |
1 files changed, 113 insertions, 0 deletions
diff --git a/arch/arm/mach-sunxi/dram_timings/a523_ddr3.c b/arch/arm/mach-sunxi/dram_timings/a523_ddr3.c new file mode 100644 index 00000000000..6e140bb1454 --- /dev/null +++ b/arch/arm/mach-sunxi/dram_timings/a523_ddr3.c @@ -0,0 +1,113 @@ +// SPDX-License-Identifier: GPL-2.0+ +/* + * sun55i A523 DDR3 timings, as programmed by Allwinner's boot0 on + * the X96QPro+ TV box. As usual very conservative timings, but probably + * the most compatible and reliable. + * + * (C) Copyright 2024 Mikhail Kalashnikov <iuncuim@gmail.com> + * Based on H616 DDR3 timings: + * (C) Copyright 2020 Jernej Skrabec <jernej.skrabec@siol.net> + */ + +#include <asm/arch/dram.h> +#include <asm/arch/cpu.h> + +void mctl_set_timing_params(u32 clk) +{ + struct sunxi_mctl_ctl_reg * const mctl_ctl = + (struct sunxi_mctl_ctl_reg *)SUNXI_DRAM_CTL0_BASE; + + /* + * formulas and constraints as of + * JEDEC DDR3 specification, for + * DDR3-1600, per JESD79-3F + */ + u8 tccd = 2; /* 4nCK */ + u8 tfaw = ns_to_t(50, clk); + u8 trrd = max(ns_to_t(6, clk), 4); /* max(6 ns, 4nCK) */ + u8 twtr = max(ns_to_t(8, clk), 4); /* max(7.5 ns, 4nCK) */ + u8 trcd = ns_to_t(15, clk); /* 13.5 ns */ + u8 trc = ns_to_t(53, clk); + u8 txp = max(ns_to_t(8, clk), 2); /* max(6 ns, 3nCK) */ + u8 trtp = max(ns_to_t(8, clk), 4); /* max(7.5 ns, 4nCK) */ + u8 trp = ns_to_t(15, clk); /* >= 13.75 ns */ + u8 tras = ns_to_t(38, clk); + u16 trefi = ns_to_t(11350, clk) / 32; + u16 trfc = ns_to_t(360, clk); /* 160 ns for 2Gb */ + u16 txsr = 4; + + u8 tmrw = 0; + u8 tmrd = 4; /* 4nCK */ + + u8 tmod = max(ns_to_t(15, clk), 12); /* max(15 ns, 12nCK) */ + u8 tcke = max(ns_to_t(6, clk), 4); /* max(5.625 ns, 3nCK)*/ + u8 tcksrx = max(ns_to_t(10, clk), 4); /* max(10 ns, 5nCK) */ + u8 tcksre = max(ns_to_t(10, clk), 4); /* max(10 ns, 5nCK) */ + u8 trasmax = (clk / 2) / 15; /* tREFI * 9 */ + + /* + * TODO: support multiple DDR3 speed grades, these values below match + * the worst case for DDR3-2133, so should be good for all frequencies, + * but use the most conversative timings. + * DDR3-1866 (DRAM_CLK=912) should also work, or tcl=6 and tcwl=4 with + * DRAM_CLK=792. Maybe even the combination of both, depending on the + * particular device. + */ + u8 tcl = 7; /* CAS latency: 14 */ + u8 tcwl = 5; /* CAS write latency: 10 */ + u8 t_rdata_en = 9; + u8 tphy_wrlat = 5; + u8 twr = 7; + + u8 tckesr = tcke + 1; /* tCKE(min) + 1nCK */ + + u8 twtp = twr + 2 + tcwl; + u8 twr2rd = twtr + 2 + tcwl; /* (WL + BL / 2 + tWTR) / 2 */ + u8 trd2wr = tcl + 3 - tcwl; + u8 txs = ns_to_t(360, clk) / 32; /* max(5nCK,tRFC+10ns)*/ + u8 txsdll = 512 / 32; /* 512 nCK */ + u8 txsabort = 4; + u8 txsfast = 4; + + /* set DRAM timing */ + writel((twtp << 24) | (tfaw << 16) | (trasmax << 8) | tras, + &mctl_ctl->dramtmg[0]); + writel((txp << 16) | (trtp << 8) | trc, &mctl_ctl->dramtmg[1]); + writel((tcwl << 24) | (tcl << 16) | (trd2wr << 8) | twr2rd, + &mctl_ctl->dramtmg[2]); + writel((tmrw << 20) | (tmrd << 12) | tmod, &mctl_ctl->dramtmg[3]); + writel((trcd << 24) | (tccd << 16) | (trrd << 8) | trp, + &mctl_ctl->dramtmg[4]); + writel((tcksrx << 24) | (tcksre << 16) | (tckesr << 8) | tcke, + &mctl_ctl->dramtmg[5]); + /* Value suggested by ZynqMP manual and used by libdram */ + writel((txp + 2) | 0x02020000, &mctl_ctl->dramtmg[6]); + writel((txsfast << 24) | (txsabort << 16) | (txsdll << 8) | txs, + &mctl_ctl->dramtmg[8]); + writel(0x00020208, &mctl_ctl->dramtmg[9]); + writel(0xe0c05, &mctl_ctl->dramtmg[10]); + writel(0x440c021c, &mctl_ctl->dramtmg[11]); + writel(8, &mctl_ctl->dramtmg[12]); + writel(0xa100002, &mctl_ctl->dramtmg[13]); + writel(txsr, &mctl_ctl->dramtmg[14]); + + clrsetbits_le32(&mctl_ctl->init[0], 0xc0000fff, 0x156); + writel(0x01f20000, &mctl_ctl->init[1]); + writel(0x00001700, &mctl_ctl->init[2]); + writel(0, &mctl_ctl->dfimisc); + writel(0x1f140004, &mctl_ctl->init[3]); + writel(0x00200000, &mctl_ctl->init[4]); + writel(0, &mctl_ctl->init[6]); /* ? */ + writel(0, &mctl_ctl->init[7]); /* ? */ + + clrsetbits_le32(&mctl_ctl->rankctl, 0xff0, 0x660); + + /* Configure DFI timing */ + writel(tphy_wrlat | 0x2000000 | (t_rdata_en << 16) | 0x808000, + &mctl_ctl->dfitmg0); + writel(0x100202, &mctl_ctl->dfitmg1); + + /* set refresh timing */ + trfc = 0; /* as written so by boot0 */ + writel((trefi << 16) | trfc, &mctl_ctl->rfshtmg); +} |