From bed85caf872714ebf53013967a695c9d63acfc68 Mon Sep 17 00:00:00 2001 From: Timur Tabi Date: Tue, 31 Oct 2006 18:13:36 -0600 Subject: mpc83xx: Add support for Errata DDR6 on MPC 834x systems CHANGELOG: * Errata DDR6, which affects all current MPC 834x processors, lists changes required to maintain compatibility with various types of DDR memory. This patch implements those changes. Signed-off-by: Timur Tabi --- cpu/mpc83xx/spd_sdram.c | 43 ++++++++++++++++++++++++++++++++++++++++++- 1 file changed, 42 insertions(+), 1 deletion(-) diff --git a/cpu/mpc83xx/spd_sdram.c b/cpu/mpc83xx/spd_sdram.c index 153848d34..8ee423463 100644 --- a/cpu/mpc83xx/spd_sdram.c +++ b/cpu/mpc83xx/spd_sdram.c @@ -112,11 +112,14 @@ static void spd_debug(spd_eeprom_t *spd) long int spd_sdram() { +#ifdef CONFIG_MPC834X + int caslat_83xx; /* For Errata DDR6 */ +#endif volatile immap_t *immap = (immap_t *)CFG_IMMRBAR; volatile ddr83xx_t *ddr = &immap->ddr; volatile law83xx_t *ecm = &immap->sysconf.ddrlaw[0]; spd_eeprom_t spd; - unsigned tmp; + unsigned int tmp, tmp1; unsigned int memsize; unsigned int law_size; unsigned char caslat, caslat_ctrl; @@ -282,6 +285,40 @@ long int spd_sdram() } } +#ifdef CONFIG_MPC834X +/* Errata DDR6 + This errata affects all MPC8349E, MPC8343E and MPC8347E processors. +*/ + if ((tmp1 >= 280) && (tmp1 < 350)) /* CSB=333 */ + { + if (spd.mid[0] == 0x2c) { + /* Micron memory running at 333 MHz */ + /* Chances are, U-Boot will crash before we get here, + but just in case, display a message and return error. */ + printf("Micron DDR not supported at 333MHz CSB\n"); + return 0; + } else if (spd.mid[0] == 0xad) { + printf("Hynix DDR does not require Errata DDR6\n"); + } else { + /* enable 2 cycle Earlier for CL=2.5 or 3 */ + ddr->debug_reg = 0x202c0000; + printf("Errata DDR6 (debug_reg=0x%x)\n", ddr->debug_reg); + } + caslat_83xx = caslat; + } + + if ((tmp1 >= 230) && (tmp1 < 280)) { /* CSB=266 */ + if (spd.mid[0] != 0x2c) /* non-Micron */ + caslat_83xx = caslat - 1; + + } + + if ((tmp1 >= 90) && (tmp1 < 230)) { /* CSB=200 */ + caslat = 3; + caslat_83xx = 2; + } +#endif + /* * note: caslat must also be programmed into ddr->sdram_mode * register. @@ -295,7 +332,11 @@ long int spd_sdram() (((picos_to_clk(spd.trp * 250) & 0x07) << 28 ) | ((picos_to_clk(spd.tras * 1000) & 0x0f ) << 24 ) | ((picos_to_clk(spd.trcd * 250) & 0x07) << 20 ) | +#ifdef CONFIG_MPC834x + ((caslat_83xx & 0x07) << 16 ) | +#else ((caslat_ctrl & 0x07) << 16 ) | +#endif (((picos_to_clk(spd.trfc * 1000) - 8) & 0x0f) << 12 ) | ( 0x300 ) | ((picos_to_clk(spd.trrd * 250) & 0x07) << 4) | 1); -- cgit v1.2.3