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-rw-r--r--board/mpc7448hpc2/asm_init.S955
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diff --git a/board/mpc7448hpc2/asm_init.S b/board/mpc7448hpc2/asm_init.S
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+/*****************************************************************************
+ * (C) Copyright 2004-05; Tundra Semiconductor Corp.
+ *
+ * Added automatic detect of SDC settings
+ * Copyright (c) 2005 Freescale Semiconductor, Inc.
+ * Maintainer tie-fei.zang@freescale.com
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License as
+ * published by the Free Software Foundation; either version 2 of
+ * the License, or (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place, Suite 330, Boston,
+ * MA 02111-1307 USA
+ ****************************************************************************/
+
+/*----------------------------------------------------------------------------
+ * FILENAME: asm_init.s
+ *
+ * Originator: Alex Bounine
+ *
+ * DESCRIPTION:
+ * Initialization code for the Tundra Tsi108 bridge chip
+ *
+ *---------------------------------------------------------------------------*/
+
+#include <config.h>
+#include <version.h>
+
+#include <ppc_asm.tmpl>
+#include <ppc_defs.h>
+#include <asm/processor.h>
+
+#include <tsi108.h>
+
+/*===========================================================================
+ * Build Configuration Options
+ */
+
+/* #define DISABLE_PBM disables usage of PB Master */
+/* #define SDC_HARDCODED_INIT config SDRAM controller with hardcoded values */
+/* #define SDC_AUTOPRECH_EN enable SDRAM auto precharge */
+
+/* ===========================================================================
+ * Hardcoded SDC settings
+ */
+
+#ifdef SDC_HARDCODED_INIT
+
+/* Micron MT9HTF6472AY-40EA1 : Unbuffered, 512MB, 400, CL3, Single Rank */
+
+#define VAL_SD_REFRESH (0x61A)
+#define VAL_SD_TIMING (0x0308336b)
+#define VAL_SD_D0_CTRL (0x07100021) /* auto-precharge disabled */
+#define VAL_SD_D0_BAR (0x0FE00000) /* 512MB @ 0x00000000 */
+#define VAL_SD_D1_CTRL (0x07100021) /* auto-precharge disabled */
+#define VAL_SD_D1_BAR (0x0FE00200) /* 512MB @ 0x20000000 */
+
+#endif /* SDC_HARDCODED_INIT */
+
+/*---------------------------------------------------------------------------
+ CPU Configuration:
+
+ CPU Address and Data Parity enables.
+
+#define CPU_AP
+#define CPU_DP
+
+===========================================================================
+ Macros
+
+ !!! Attention !!! Macros LOAD_PTR, LOAD_U32 and LOAD_MEM defined below are
+ expected to work correctly for the CSR space within 32KB range.
+
+ LOAD_PTR and LOAD_U32 - load specified register with a 32 bit constant.
+ These macros are absolutely identical except their names. This difference
+ is provided intentionally for better readable code.
+ -------------------------------------------------------------------------*/
+
+#define LOAD_PTR(reg,const32) \
+ addis reg,r0,const32@h; ori reg,reg,const32@l
+
+#define LOAD_U32(reg,const32) \
+ addis reg,r0,const32@h; ori reg,reg,const32@l
+
+/* LOADMEM initializes a register with the contents of a specified 32-bit memory
+ location, usually a CSR value.*/
+
+#define LOAD_MEM(reg,addr32) \
+ addis reg,r0,addr32@ha; lwz reg,addr32@l(reg)
+
+#ifndef SDC_HARDCODED_INIT
+sdc_clk_sync:
+ /* MHz: 0,0,183,100,133,167,200,233 */
+ .long 0,0, 6, 10, 8, 6, 5, 4 /* nSec */
+#endif
+
+/*===========================================================================
+ board_asm_init() - early initialization function. Coded to be portable to
+ dual-CPU configuration.
+ Checks CPU number and performs board HW initialization if called for CPU0.
+
+ Registers used: r3,r4,r5,r6,r19,r29
+===========================================================================
+
+---------------------------------------------------------------------------
+ NOTE: For dual-CPU configuration only CPU0 is allowed to configure Tsi108
+ and the rest of the board. Current implementation demonstrates two
+ possible ways to identify CPU number:
+ - for MPC74xx platform: uses MSSCR0[ID] bit as defined in UM.
+ - for PPC750FX/GX boards: uses WHO_AM_I bit reported by Tsi108.
+---------------------------------------------------------------------------*/
+
+ .globl board_asm_init
+board_asm_init:
+
+ mflr r19 /* Save LR to be able return later. */
+
+ bl icache_enable /* Enable icache to reduce reads from flash. */
+
+ /* Initialize pointer to Tsi108 register space
+ -------------------------------------------------------------------------*/
+
+ LOAD_PTR(r29,CFG_TSI108_CSR_RST_BASE)/* r29 - pointer to tsi108 CSR space */
+ ori r4,r29,TSI108_PB_REG_OFFSET
+
+ /*-------------------------------------------------------------------------
+ Check Processor Version Number */
+
+ mfspr r3, PVR
+ rlwinm r3,r3,16,16,23 /* get ((Processor Version Number) & 0xFF00) */
+
+ cmpli 0,0,r3,0x8000 /* MPC74xx */
+ bne cont_brd_init
+
+ /* ------------------------------------------
+ For MPC744x/5x enable extended BATs[4-7]
+ Sri: Set HIGH_BAT_EN and XBSEN, and SPD =1
+ to disable prefetch
+ */
+
+ mfspr r5, HID0
+ oris r5, r5, 0x0080 /* Set HID0[HIGH_BAT_EN] bit #8 */
+ ori r5, r5, 0x0380 /* Set SPD,XBSEN,SGE bits #22,23,24 */
+ mtspr HID0, r5
+ isync
+ sync
+
+ /* Adding code to disable external interventions in MPX bus mode */
+ mfspr r3, 1014
+ oris r3, r3, 0x0100 /* Set the EIDIS bit in MSSCR0: bit 7 */
+ mtspr 1014, r3
+ isync
+ sync
+
+ /* Sri: code to enable FP unit */
+ mfmsr r3
+ ori r3, r3, 0x2000
+ mtmsr r3
+ isync
+ sync
+
+#if(1) /* def CONFIG_DUAL_CPU
+ -------------------------------------------------------------------------
+ For MPC74xx processor, use MSSCR0[ID] bit to identify CPU number.
+ */
+
+ mfspr r3,1014 /* read MSSCR0 */
+ rlwinm. r3,r3,27,31,31 /* get processor ID number */
+ mtspr SPRN_PIR,r3 /* Save CPU ID */
+ sync
+ bne init_done
+ b do_tsi108_init
+
+cont_brd_init:
+
+ /* An alternative method of checking the processor number (in addition
+ to configuration using MSSCR0[ID] bit on MPC74xx).
+ Good for IBM PPC750FX/GX.
+ */
+
+ lwz r3,PB_BUS_MS_SELECT(r4) /* read PB_ID register */
+ rlwinm. r3,r3,24,31,31 /* get processor ID number */
+
+ bne init_done
+
+#else
+
+cont_brd_init:
+
+#endif /* CONFIG_DUAL_CPU */
+
+ /* Initialize Tsi108 chip
+ ---------------------------------------------------------------------------
+ */
+
+do_tsi108_init:
+
+ /*--------------------------------------------------------------------------
+ Adjust HLP/Flash parameters. By default after reset the HLP port is set
+ to support slow devices. Better performance can be achived when an optimal
+ parameters are used for specific EPROM device.
+ NOTE: This should be performed ASAP for the emulation platform because
+ it has 5MHz HLP clocking.
+ */
+
+#ifdef CONFIG_TSI108EMU
+ ori r4,r29,TSI108_HLP_REG_OFFSET
+ LOAD_U32(r5,0x434422c0)
+ stw r5,0x08(r4) /* set HLP B0_CTRL0 */
+ sync
+ LOAD_U32(r5,0xd0012000)
+ stw r5,0x0c(r4) /* set HLP B0_CTRL1 */
+ sync
+#endif
+
+ /* -------------------------------------------------------------------------
+ * Initialize PB interface.
+ */
+
+ ori r4,r29,TSI108_PB_REG_OFFSET
+
+#if (CFG_TSI108_CSR_BASE != CFG_TSI108_CSR_RST_BASE)
+ /* Relocate (if required) Tsi108 registers. Set new value for PB_REG_BAR:
+ * Note we are in the 32-bit address mode.
+ */
+ LOAD_U32(r5,(CFG_TSI108_CSR_BASE | 0x01)) /* value for PB_REG_BAR: BA + EN*/
+ stw r5,PB_REG_BAR(r4)
+ andis. r29,r5,0xFFFF
+ sync
+
+ ori r4,r29,TSI108_PB_REG_OFFSET
+#endif
+
+ /* Set PB Slave configuration register */
+
+/* LOAD_U32(r5,0x000024C7) value for PB_SCR: TEA enabled,AACK delay = 7 */
+ LOAD_U32(r5,0x00002481) /* value for PB_SCR: TEA enabled,AACK delay = 1 */
+ lwz r3, PB_RSR(r4) /* get PB bus mode */
+ xori r3,r3,0x0001 /* mask PB_BMODE: r3 -> (0 = 60X, 1 = MPX) */
+ rlwimi r5,r3,14,17,17 /* for MPX: set DTI_MODE bit */
+ stw r5,PB_SCR(r4)
+ sync
+
+ /* Configure PB Arbiter */
+
+ lwz r5,PB_ARB_CTRL(r4) /* Read PB Arbiter Control Register */
+ li r3, 0x00F0 /* ARB_PIPELINE_DEP mask */
+#ifdef DISABLE_PBM
+ ori r3,r3,0x1000 /* add PBM_EN to clear (enabled by default) */
+#endif
+ andc r5,r5,r3 /* Clear the masked bit fields */
+/* ori r5,r5,0x0040 Set pipeline depth 4
+ ori r5,r5,0x0080 Set pipeline depth 8
+ ori r5,r5,0x0020 !!!avb Testing: set pipeline depth 2 */
+ ori r5,r5,0x0001
+ stw r5,PB_ARB_CTRL(r4)
+
+#if (0) /* currently using the default settings for PBM after reset */
+ LOAD_U32(r5,0x) /* value for PB_MCR */
+ stw r5,PB_MCR(r4)
+ sync
+
+ LOAD_U32(r5,0x) /* value for PB_MCMD */
+ stw r5,PB_MCMD(r4)
+ sync
+#endif
+
+/* Disable or enable PVT based on processor bus frequency
+ 1. Read CG_PWRUP_STATUS register field bits 18,17,16
+ 2. See if the value is < or > 133mhz (18:16 = 100)
+ 3. If > enable PVT
+ */
+
+ LOAD_U32(r3,0xC0002234)
+ lwz r3,0(r3)
+ rlwinm r3,r3,16,29,31
+
+ cmpi 0,0,r3,0x0004
+ bgt sdc_init
+
+#ifndef CONFIG_TSI108EMU
+ /* FIXME: Disable PB calibration control for any real Tsi108 board */
+ li r5,0x0101 /* disable calibration control */
+ stw r5,PB_PVT_CTRL2(r4)
+ sync
+#endif
+
+/*---------------------------------------------------------------------------
+ Initialize SDRAM controller.
+----------------------------------------------------------------------------*/
+
+sdc_init:
+
+#ifndef SDC_HARDCODED_INIT
+ /* get SDC clock prior doing sdram controller autoconfig */
+ ori r4,r29,TSI108_CLK_REG_OFFSET /* r4 - ptr to CG registers */
+ lwz r3, CG_PWRUP_STATUS(r4) /* get CG configuration */
+ rlwinm r3,r3,12,29,31 /* r3 - SD clk */
+ lis r5,sdc_clk_sync@h
+ ori r5,r5,sdc_clk_sync@l
+ /* Sri: At this point check if r3 = 001. If yes,
+ * the memory frequency should be same as the
+ * MPX bus frequency
+ */
+ cmpi 0,0,r3,0x0001
+ bne get_nsec
+ lwz r6, CG_PWRUP_STATUS(r4)
+ rlwinm r6,r6,16,29,31
+ mr r3,r6
+
+get_nsec:
+ rlwinm r3,r3,2,0,31
+ lwzx r9,r5,r3 /* get SD clk rate in nSec */
+ /* ATTN: r9 will be used by SPD routine */
+#endif /* !SDC_HARDCODED_INIT */
+
+ ori r4,r29,TSI108_SD_REG_OFFSET /* r4 - ptr to SDRAM registers */
+
+ /* Initialize SDRAM controller. SDRAM Size = 512MB, One DIMM. */
+
+ LOAD_U32(r5,0x00)
+ stw r5,SD_INT_ENABLE(r4) /* Ensure that interrupts are disabled */
+#ifdef ENABLE_SDRAM_ECC
+ li r5, 0x01
+#endif /* ENABLE_SDRAM_ECC */
+ stw r5,SD_ECC_CTRL(r4) /* Enable/Disable ECC */
+ sync
+
+#ifdef SDC_HARDCODED_INIT /* config sdram controller with hardcoded values */
+
+ /* First read the CG_PWRUP_STATUS register to get the
+ memory speed from bits 22,21,20 */
+
+ LOAD_U32(r3,0xC0002234)
+ lwz r3,0(r3)
+ rlwinm r3,r3,12,29,31
+
+ /* Now first check for 166, then 200, or default */
+
+ cmpi 0,0,r3,0x0005
+ bne check_for_200mhz
+
+ /* set values for 166 Mhz memory speed */
+
+ /* Set refresh rate and timing parameters */
+ LOAD_U32(r5,0x00000515)
+ stw r5,SD_REFRESH(r4)
+ LOAD_U32(r5,0x03073368)
+ stw r5,SD_TIMING(r4)
+ sync
+
+ /* Initialize DIMM0 control and BAR registers */
+ LOAD_U32(r5,VAL_SD_D0_CTRL) /* auto-precharge disabled */
+#ifdef SDC_AUTOPRECH_EN
+ oris r5,r5,0x0001 /* set auto precharge EN bit */
+#endif
+ stw r5,SD_D0_CTRL(r4)
+ LOAD_U32(r5,VAL_SD_D0_BAR)
+ stw r5,SD_D0_BAR(r4)
+ sync
+
+ /* Initialize DIMM1 control and BAR registers
+ * (same as dimm 0, next 512MB, disabled)
+ */
+ LOAD_U32(r5,VAL_SD_D1_CTRL) /* auto-precharge disabled */
+#ifdef SDC_AUTOPRECH_EN
+ oris r5,r5,0x0001 /* set auto precharge EN bit */
+#endif
+ stw r5,SD_D1_CTRL(r4)
+ LOAD_U32(r5,VAL_SD_D1_BAR)
+ stw r5,SD_D1_BAR(r4)
+ sync
+
+ b sdc_init_done
+
+check_for_200mhz:
+
+ cmpi 0,0,r3,0x0006
+ bne set_default_values
+
+ /* set values for 200Mhz memory speed */
+
+ /* Set refresh rate and timing parameters */
+ LOAD_U32(r5,0x0000061a)
+ stw r5,SD_REFRESH(r4)
+ LOAD_U32(r5,0x03083348)
+ stw r5,SD_TIMING(r4)
+ sync
+
+ /* Initialize DIMM0 control and BAR registers */
+ LOAD_U32(r5,VAL_SD_D0_CTRL) /* auto-precharge disabled */
+#ifdef SDC_AUTOPRECH_EN
+ oris r5,r5,0x0001 /* set auto precharge EN bit */
+#endif
+ stw r5,SD_D0_CTRL(r4)
+ LOAD_U32(r5,VAL_SD_D0_BAR)
+ stw r5,SD_D0_BAR(r4)
+ sync
+
+ /* Initialize DIMM1 control and BAR registers
+ * (same as dimm 0, next 512MB, disabled)
+ */
+ LOAD_U32(r5,VAL_SD_D1_CTRL) /* auto-precharge disabled */
+#ifdef SDC_AUTOPRECH_EN
+ oris r5,r5,0x0001 /* set auto precharge EN bit */
+#endif
+ stw r5,SD_D1_CTRL(r4)
+ LOAD_U32(r5,VAL_SD_D1_BAR)
+ stw r5,SD_D1_BAR(r4)
+ sync
+
+ b sdc_init_done
+
+set_default_values:
+
+ /* Set refresh rate and timing parameters */
+ LOAD_U32(r5,VAL_SD_REFRESH)
+ stw r5,SD_REFRESH(r4)
+ LOAD_U32(r5,VAL_SD_TIMING)
+ stw r5,SD_TIMING(r4)
+ sync
+
+ /* Initialize DIMM0 control and BAR registers */
+ LOAD_U32(r5,VAL_SD_D0_CTRL) /* auto-precharge disabled */
+#ifdef SDC_AUTOPRECH_EN
+ oris r5,r5,0x0001 /* set auto precharge EN bit */
+#endif
+ stw r5,SD_D0_CTRL(r4)
+ LOAD_U32(r5,VAL_SD_D0_BAR)
+ stw r5,SD_D0_BAR(r4)
+ sync
+
+ /* Initialize DIMM1 control and BAR registers
+ * (same as dimm 0, next 512MB, disabled)
+ */
+ LOAD_U32(r5,VAL_SD_D1_CTRL) /* auto-precharge disabled */
+#ifdef SDC_AUTOPRECH_EN
+ oris r5,r5,0x0001 /* set auto precharge EN bit */
+#endif
+ stw r5,SD_D1_CTRL(r4)
+ LOAD_U32(r5,VAL_SD_D1_BAR)
+ stw r5,SD_D1_BAR(r4)
+ sync
+
+#else /* !SDC_HARDCODED_INIT */
+
+ bl tsi108_sdram_spd /* automatically detect SDC settings */
+
+#endif /* SDC_HARDCODED_INIT */
+
+sdc_init_done:
+
+#ifdef DISABLE_PBM
+ LOAD_U32(r5,0x00000030) /* PB_EN + OCN_EN */
+#else
+ LOAD_U32(r5,0x00000230) /* PB_EN + OCN_EN + PB/OCN=80/20 */
+#endif /* DISABLE_PBM */
+
+#ifdef CONFIG_TSI108EMU
+ oris r5,r5,0x0010 /* set EMULATION_MODE bit */
+#endif
+
+ stw r5,SD_CTRL(r4)
+ eieio
+ sync
+
+ /* Enable SDRAM access */
+
+ oris r5,r5,0x8000 /* start SDC: set SD_CTRL[ENABLE] bit */
+ stw r5,SD_CTRL(r4)
+ sync
+
+wait_init_complete:
+ lwz r5,SD_STATUS(r4)
+ andi. r5,r5,0x0001
+ beq wait_init_complete /* wait until SDRAM initialization is complete */
+
+/*---------------------------------------------------------------------------
+ Map SDRAM into the processor bus address space
+---------------------------------------------------------------------------*/
+
+ ori r4,r29,TSI108_PB_REG_OFFSET
+
+ /* Setup BARs associated with direct path PB<->SDRAM */
+
+ /* PB_SDRAM_BAR1:
+ provides a direct path to the main system memory (cacheable SDRAM) */
+
+ LOAD_U32(r5, 0x00000011) /* BA=0,Size=512MB, ENable, No Addr.Translation */
+ stw r5,PB_SDRAM_BAR1(r4)
+ sync
+
+ /* Make sure that PB_SDRAM_BAR1 decoder is set
+ (to allow following immediate read from SDRAM) */
+ lwz r5,PB_SDRAM_BAR1(r4)
+ sync
+
+ /* PB_SDRAM_BAR2:
+ provides non-cacheable alias (via the direct path) to main system memory.
+ Size = 512MB, ENable, Addr.Translation - ON,
+ BA = 0x0_40000000, TA = 0x0_00000000 */
+
+ LOAD_U32(r5, 0x40010011)
+ stw r5,PB_SDRAM_BAR2(r4)
+ sync
+
+ /* Make sure that PB_SDRAM_BAR2 decoder is set
+ (to allow following immediate read from SDRAM) */
+ lwz r5,PB_SDRAM_BAR2(r4)
+ sync
+
+
+init_done:
+
+ /* All done. Restore LR and return. */
+ mtlr r19
+ blr
+
+#if (0)
+/*===========================================================================
+ init_cpu1
+
+ This routine enables CPU1 on the dual-processor system.
+===========================================================================*/
+
+ .global enable_cpu1
+enable_cpu1:
+
+ lis r3,Tsi108_Base@ha /* Get Grendel CSR Base Addr */
+ addi r3,r3,Tsi108_Base@l
+ lwz r3,0(r3) /* R3 = CSR Base Addr */
+ ori r4,r3,TSI108_PB_REG_OFFSET
+ lwz r3,PB_ARB_CTRL(r4) /* Read PB Arbiter Control Register */
+ ori r3,r3,0x0200 /* Set M1_EN bit */
+ stw r3,PB_ARB_CTRL(r4)
+
+ blr
+#endif
+
+/*===========================================================================
+ enable_EI
+
+ Enable CPU core external interrupt
+===========================================================================*/
+
+ .global enable_EI
+enable_EI:
+ mfmsr r3
+ ori r3,r3,0x8000 /* set EE bit */
+ mtmsr r3
+ blr
+
+/*===========================================================================
+ disable_EI
+
+ Disable CPU core external interrupt
+===========================================================================*/
+
+ .global disable_EI
+disable_EI:
+ mfmsr r3
+ li r4,-32768 /* aka "li r4,0x8000" */
+ andc r3,r3,r4 /* clear EE bit */
+ mtmsr r3
+ blr
+
+#ifdef ENABLE_SDRAM_ECC
+/*===========================================================================
+ enable_ECC
+
+ enables SDRAM ECC
+===========================================================================*/
+
+ .global enable_ECC
+enable_ECC:
+ ori r4,r29,TSI108_SD_REG_OFFSET
+ lwz r3,SD_ECC_CTRL(r4) /* Read SDRAM ECC Control Register */
+ ori r3,r3,0x0001 /* Set ECC_EN bit */
+ stw r3,SD_ECC_CTRL(r4)
+ blr
+
+/*===========================================================================
+ clear_ECC_err
+
+ Clears all pending SDRAM ECC errors
+ (normally after SDRAM scrubbing/initialization)
+===========================================================================*/
+
+ .global clear_ECC_err
+clear_ECC_err:
+ ori r4,r29,TSI108_SD_REG_OFFSET
+/* lwz r3,SD_INT_STATUS(r4) Read SDRAM ECC Control Register */
+ ori r3,r0,0x0030 /* ECC_UE_INT + ECC_CE_INT bits */
+ stw r3,SD_INT_STATUS(r4)
+ blr
+
+#endif /* ENABLE_SDRAM_ECC */
+
+#ifndef SDC_HARDCODED_INIT
+
+/********************************************************************
+ * SDRAM SPD Support
+ */
+
+#define SD_I2C_CTRL1 (0x400)
+#define SD_I2C_CTRL2 (0x404)
+#define SD_I2C_RD_DATA (0x408)
+#define SD_I2C_WR_DATA (0x40C)
+
+/*
+ * SDRAM SPD Support Macros
+ */
+
+#define SPD_DIMM0 (0x00000100)
+#define SPD_DIMM1 (0x00000200) /* SPD_DIMM1 was 0x00000000 */
+
+#define SPD_RDIMM (0x01)
+#define SPD_UDIMM (0x02)
+
+#define SPD_CAS_3 0x8
+#define SPD_CAS_4 0x10
+#define SPD_CAS_5 0x20
+
+#define ERR_NO_DIMM_FOUND (0xdb0)
+#define ERR_TRAS_FAIL (0xdb1)
+#define ERR_TRCD_FAIL (0xdb2)
+#define ERR_TRP_FAIL (0xdb3)
+#define ERR_TWR_FAIL (0xdb4)
+#define ERR_UNKNOWN_PART (0xdb5)
+#define ERR_NRANK_INVALID (0xdb6)
+#define ERR_DIMM_SIZE (0xdb7)
+#define ERR_ADDR_MODE (0xdb8)
+#define ERR_RFRSH_RATE (0xdb9)
+#define ERR_DIMM_TYPE (0xdba)
+#define ERR_CL_VALUE (0xdbb)
+#define ERR_TRFC_FAIL (0xdbc)
+
+/* READ_SPD requirements:
+ * byte - byte address in SPD device (0 - 255)
+ * r3 = will return data read from I2C Byte location
+ * r4 - unchanged (SDC base addr)
+ * r5 - clobbered in routine (I2C status)
+ * r10 - number of DDR slot where first SPD device is detected
+ */
+
+#define READ_SPD(byte_num) \
+ addis r3, 0, byte_num@l;\
+ or r3, r3, r10;\
+ ori r3, r3, 0x0A;\
+ stw r3, SD_I2C_CTRL1(r4);\
+ li r3, I2C_CNTRL2_START;\
+ stw r3, SD_I2C_CTRL2(r4);\
+ eieio;\
+ sync;\
+ li r3, 0x100;\
+1: ;\
+ addic. r3, r3, -1;\
+ bne 1b;\
+2: ;\
+ lwz r5, SD_I2C_CTRL2(r4);\
+ rlwinm. r3,r5,0,23,23;\
+ bne 2b;\
+ rlwinm. r3,r5,0,3,3;\
+ lwz r3, SD_I2C_RD_DATA(r4)
+
+#define SPD_MIN_RFRSH (0x80)
+#define SPD_MAX_RFRSH (0x85)
+
+refresh_rates: /* in nSec */
+ .long 15625 /* Normal (0x80) */
+ .long 3900 /* Reduced 0.25x (0x81) */
+ .long 7800 /* Reduced 0.5x (0x82) */
+ .long 31300 /* Extended 2x (0x83) */
+ .long 62500 /* Extended 4x (0x84) */
+ .long 125000 /* Extended 8x (0x85) */
+
+/*===========================================================================
+ * tsi108_sdram_spd
+ *
+ * Inittializes SDRAM Controller using DDR2 DIMM Serial Presence Detect data
+ * Uses registers: r4 - SDC base address (not changed)
+ * r9 - SDC clocking period in nSec
+ * Changes registers: r3,r5,r6,r7,r8,r10,r11
+ *==========================================================================*/
+
+tsi108_sdram_spd:
+
+ li r10,SPD_DIMM0
+ xor r11,r11,r11 /* DIMM Base Address: starts from 0 */
+
+do_first_dimm:
+
+ /**************************************
+ * Program Refresh Rate Register
+ */
+
+ READ_SPD(12) /* get Refresh Rate */
+ beq check_next_slot
+ li r5, ERR_RFRSH_RATE
+ cmpi 0,0,r3,SPD_MIN_RFRSH
+ ble spd_fail
+ cmpi 0,0,r3,SPD_MAX_RFRSH
+ bgt spd_fail
+ addi r3,r3,-SPD_MIN_RFRSH
+ rlwinm r3,r3,2,0,31
+ lis r5,refresh_rates@h
+ ori r5,r5,refresh_rates@l
+ lwzx r5,r5,r3 /* get refresh rate in nSec */
+ divwu r5,r5,r9 /* calculate # of SDC clocks */
+ stw r5,SD_REFRESH(r4) /* Set refresh rate */
+ sync
+
+ /**************************************
+ * Program SD Timing Register
+ */
+
+ li r7, 0 /* clear r7 prior parameter collection */
+
+ READ_SPD(20) /* get DIMM type: Registered or Unbuffered */
+ beq spd_read_fail
+ li r5, ERR_DIMM_TYPE
+ cmpi 0,0,r3,SPD_UDIMM
+ beq do_cl
+ cmpi 0,0,r3,SPD_RDIMM
+ bne spd_fail
+ oris r7,r7,0x1000 /* set SD_TIMING[DIMM_TYPE] bit */
+
+do_cl:
+ READ_SPD(18) /* Get CAS Latency */
+ beq spd_read_fail
+ li r5,ERR_CL_VALUE
+ andi. r6,r3,SPD_CAS_3
+ beq cl_4
+ li r6,3
+ b set_cl
+cl_4:
+ andi. r6,r3,SPD_CAS_4
+ beq cl_5
+ li r6,4
+ b set_cl
+cl_5:
+ andi. r6,r3,SPD_CAS_5
+ beq spd_fail
+ li r6,5
+set_cl:
+ rlwimi r7,r6,24,5,7
+
+ READ_SPD(30) /* Get tRAS */
+ beq spd_read_fail
+ divwu r6,r3,r9
+ mullw r8,r6,r9
+ subf. r8,r8,r3
+ beq set_tras
+ addi r6,r6,1
+set_tras:
+ li r5,ERR_TRAS_FAIL
+ cmpi 0,0,r6,0x0F /* max supported value */
+ bgt spd_fail
+ rlwimi r7,r6,16,12,15
+
+ READ_SPD(29) /* Get tRCD */
+ beq spd_read_fail
+ rlwinm r3,r3,30,2,31/* right shift tRCD by 2 bits as per DDR2 spec */
+ divwu r6,r3,r9
+ mullw r8,r6,r9
+ subf. r8,r8,r3
+ beq set_trcd
+ addi r6,r6,1
+set_trcd:
+ li r5,ERR_TRCD_FAIL
+ cmpi 0,0,r6,0x07 /* max supported value */
+ bgt spd_fail
+ rlwimi r7,r6,12,17,19
+
+ READ_SPD(27) /* Get tRP value */
+ beq spd_read_fail
+ rlwinm r3,r3,30,2,31 /* right shift tRP by 2 bits as per DDR2 spec */
+ divwu r6,r3,r9
+ mullw r8,r6,r9
+ subf. r8,r8,r3
+ beq set_trp
+ addi r6,r6,1
+set_trp:
+ li r5,ERR_TRP_FAIL
+ cmpi 0,0,r6,0x07 /* max supported value */
+ bgt spd_fail
+ rlwimi r7,r6,8,21,23
+
+ READ_SPD(36) /* Get tWR value */
+ beq spd_read_fail
+ rlwinm r3,r3,30,2,31 /* right shift tWR by 2 bits as per DDR2 spec */
+ divwu r6,r3,r9
+ mullw r8,r6,r9
+ subf. r8,r8,r3
+ beq set_twr
+ addi r6,r6,1
+set_twr:
+ addi r6,r6,-1 /* Tsi108 SDC always gives one extra clock */
+ li r5,ERR_TWR_FAIL
+ cmpi 0,0,r6,0x07 /* max supported value */
+ bgt spd_fail
+ rlwimi r7,r6,5,24,26
+
+ READ_SPD(42) /* Get tRFC */
+ beq spd_read_fail
+ li r5, ERR_TRFC_FAIL
+ /* Tsi108 spec: tRFC=(tRFC + 1)/2 */
+ addi r3,r3,1
+ rlwinm. r3,r3,31,1,31 /* divide by 2 */
+ beq spd_fail
+ divwu r6,r3,r9
+ mullw r8,r6,r9
+ subf. r8,r8,r3
+ beq set_trfc
+ addi r6,r6,1
+set_trfc:
+ cmpi 0,0,r6,0x1F /* max supported value */
+ bgt spd_fail
+ rlwimi r7,r6,0,27,31
+
+ stw r7,SD_TIMING(r4)
+ sync
+
+ /*=====================================================================
+ * The following two registers are set on per-DIMM basis.
+ * The SD_REFRESH and SD_TIMING settings are common for both DIMMS
+ *=====================================================================
+ */
+
+do_each_dimm:
+
+ /*****************************************
+ * Program SDRAM DIMM Control Register
+ */
+
+ li r7, 0 /* clear r7 prior parameter collection */
+
+ READ_SPD(13) /* Get Primary SDRAM Width */
+ beq spd_read_fail
+ cmpi 0,0,r3,4 /* Check for 4-bit SDRAM */
+ beq do_nbank
+ oris r7,r7,0x0010 /* Set MEM_WIDTH bit */
+
+do_nbank:
+ READ_SPD(17) /* Get Number of banks on SDRAM device */
+ beq spd_read_fail
+ /* Grendel only distinguish betw. 4 or 8-bank memory parts */
+ li r5,ERR_UNKNOWN_PART /* non-supported memory part */
+ cmpi 0,0,r3,4
+ beq do_nrank
+ cmpi 0,0,r3,8
+ bne spd_fail
+ ori r7,r7,0x1000
+
+do_nrank:
+ READ_SPD(5) /* Get # of Ranks */
+ beq spd_read_fail
+ li r5,ERR_NRANK_INVALID
+ andi. r6,r3,0x7 /* Use bits [2..0] only */
+ beq do_addr_mode
+ cmpi 0,0,r6,1
+ bgt spd_fail
+ rlwimi r7,r6,8,23,23
+
+do_addr_mode:
+ READ_SPD(4) /* Get # of Column Addresses */
+ beq spd_read_fail
+ li r5, ERR_ADDR_MODE
+ andi. r3,r3,0x0f /* cut off reserved bits */
+ cmpi 0,0,r3,8
+ ble spd_fail
+ cmpi 0,0,r3,15
+ bgt spd_fail
+ addi r6,r3,-8 /* calculate ADDR_MODE parameter */
+ rlwimi r7,r6,4,24,27 /* set ADDR_MODE field */
+
+set_dimm_ctrl:
+#ifdef SDC_AUTOPRECH_EN
+ oris r7,r7,0x0001 /* set auto precharge EN bit */
+#endif
+ ori r7,r7,1 /* set ENABLE bit */
+ cmpi 0,0,r10,SPD_DIMM0
+ bne 1f
+ stw r7,SD_D0_CTRL(r4)
+ sync
+ b set_dimm_bar
+1:
+ stw r7,SD_D1_CTRL(r4)
+ sync
+
+
+ /********************************************
+ * Program SDRAM DIMMx Base Address Register
+ */
+
+set_dimm_bar:
+ READ_SPD(5) /* get # of Ranks */
+ beq spd_read_fail
+ andi.r7,r3,0x7
+ addi r7,r7,1
+ READ_SPD(31) /* Read DIMM rank density */
+ beq spd_read_fail
+ rlwinm r5,r3,27,29,31
+ rlwinm r6,r3,3,24,28
+ or r5,r6,r5 /* r5 = Normalized Rank Density byte */
+ lis r8, 0x0080 /* 128MB >> 4 */
+ mullw r8,r8,r5 /* r8 = (rank_size >> 4) */
+ mullw r8,r8,r7 /* r8 = (DIMM_size >> 4) */
+ neg r7,r8
+ rlwinm r7,r7,28,4,31
+ or r7,r7,r11 /* set ADDR field */
+ rlwinm r8,r8,12,20,31
+ add r11,r11,r8 /* set Base Addr for next DIMM */
+
+ cmpi 0,0,r10,SPD_DIMM0
+ bne set_dimm1_size
+ stw r7,SD_D0_BAR(r4)
+ sync
+ li r10,SPD_DIMM1
+ READ_SPD(0)
+ bne do_each_dimm
+ b spd_done
+
+set_dimm1_size:
+ stw r7,SD_D1_BAR(r4)
+ sync
+spd_done:
+ blr
+
+check_next_slot:
+ cmpi 0,0,r10,SPD_DIMM1
+ beq spd_read_fail
+ li r10,SPD_DIMM1
+ b do_first_dimm
+spd_read_fail:
+ ori r3,r0,0xdead
+ b err_hung
+spd_fail:
+ li r3,0x0bad
+ sync
+err_hung: /* hang here for debugging */
+ nop
+ nop
+ b err_hung
+
+#endif /* !SDC_HARDCODED_INIT */
+