[U-Boot] [PATCH v1 07/18] board: Add Microchip PIC32MZ[DA] Starter Kit board.

[Purna Chandra Mandal <purna.mandal@microchip.com>]

On 12/17/2015 11:28 PM, Marek Vasut wrote:

> On Thursday, December 17, 2015 at 06:30:38 PM, Purna Chandra Mandal wrote:
> [...]
>
>> diff --git a/board/microchip/pic32mzda/config.mk
>> b/board/microchip/pic32mzda/config.mk new file mode 100644
>> index 0000000..a12e712
>> --- /dev/null
>> +++ b/board/microchip/pic32mzda/config.mk
>> @@ -0,0 +1,4 @@
>> +#
>> +# Microchip PIC32MZ[DA] board (PIC32 SoC powered by MIPS M14KEc CPU)
>> +#
>> +CONFIG_SYS_TEXT_BASE = 0x9d004000
>> diff --git a/board/microchip/pic32mzda/ddr.c
>> b/board/microchip/pic32mzda/ddr.c new file mode 100644
>> index 0000000..31a44fa
>> --- /dev/null
>> +++ b/board/microchip/pic32mzda/ddr.c
>> @@ -0,0 +1,389 @@
>> +/*
>> + * (c) 2015 Paul Thacker <paul.thacker@microchip.com>
>> + *
>> + * SPDX-License-Identifier:    GPL-2.0+
>> + *
>> + */
>> +
>> +#include <asm/io.h>
>> +#include <stdint.h>
>> +#include <config.h>
>> +#include <linux/kernel.h>
>> +#include <asm/mipsregs.h>
>> +#include <asm/arch-pic32/pic32.h>
>> +
>> +#include "ddr.h"
>> +
>> +/* macros */
>> +#define hc_clk_dly(dly)        \
>> +    (max_t(u32, (DIV_ROUND_UP((dly), CLK_PERIOD)), 2) - 2)
>> +
>> +/* Host Commands */
>> +#define IDLE_NOP        0x00FFFFFF
>> +#define PRECH_ALL_CMD        0x00FFF401
>> +#define REF_CMD            0x00FFF801
>> +#define LOAD_MODE_CMD        0x00FFF001
>> +#define CKE_LOW            0x00FFEFFE
>> +
>> +#define NUM_HOST_CMDS        12
>> +
>> +/* DDR address decoding */
>> +#define COL_HI_RSHFT        0
>> +#define COL_HI_MASK        0
>> +#define COL_LO_MASK        ((1 << COL_BITS) - 1)
>> +
>> +#define BA_RSHFT        COL_BITS
>> +#define BANK_ADDR_MASK        ((1 << BA_BITS) - 1)
>> +
>> +#define ROW_ADDR_RSHIFT        (BA_RSHFT + BA_BITS)
>> +#define ROW_ADDR_MASK        ((1 << ROW_BITS) - 1)
>> +
>> +#define CS_ADDR_RSHIFT        0
>> +#define CS_ADDR_MASK        0
>> +
>> +/* MPLL freq is 400MHz */
>> +#define CLK_PERIOD              2500    /* 2500 psec */
>> +#define CTRL_CLK_PERIOD         (CLK_PERIOD * 2)
>> +
>> +/* Arbiter */
>> +#define NUM_AGENTS              5
>> +#define MIN_LIM_WIDTH           5
>> +#define RQST_PERIOD_WIDTH       8
>> +#define MIN_CMDACPT_WIDTH       8
>> +
>> +#define EN_AUTO_PRECH           0
>> +#define SB_PRI                  1
>> +#define BIG_ENDIAN              0
>> +#define HALF_RATE_MODE          1
>> +
>> +/*************************************************************************
>> ****/ +/* DDR definitions */
>> +/*************************************************************************
>> ****/ +
>> +/* DDR Address Mapping: CS, ROW, BA, COL */
>> +#define COL_BITS    10
>> +#define ROW_BITS    13
>> +#define BA_BITS        3
>> +#define CS_BITS        1
> OK, so how many copies of this code will we have by the end of the day ?
> One for each board ? That ain't gonna work ...

Ack. Will re-organize this code into two parts - common code will go to
drivers/ddr/ and board specific parameters (like arbiter parameters, DDR2 timing parameters)
will be separated. 

>> +/* DDR constants */
>> +#define BL        2    /* Burst length in cycles */
>> +
>> +/* default CAS latency for all speed grades */
>> +#define RL        5
>> +
>> +/* default write latency for all speed grades = CL-1 */
>> +#define WL        4
>> +
>> +#define MAX_BURST    3
>> +
>> +/* NOTE: DDR data from Micron MT47H64M16HR-3 data sheet */
>> +#define tRFC_MIN    127500    /* psec */
>> +#define tWR        15000    /* psec */
>> +#define tRP        12500    /* psec */
>> +#define tRCD        12500    /* psec */
>> +#define tRRD        7500    /* psec */
> This is board specific, but the code is not I believe. So the common code
> should go into drivers/ddr/

ack.

>> +/* tRRD_TCK is a minimum of 2 clk periods, regardless of clk freq */
>> +#define tRRD_TCK    2
>> +#define tWTR        7500    /* psec */
> [...]
>
>> +    /* ODT Config */
>> +    writel(0x00000000, DDR2ODTCFG);
>> +    writel(0x00010000, DDR2ODTENCFG);/* WREN on CS */
>> +
>> +    writel(((RL - 3) << 8) | ((WL - 3) << 12) | (2 << 16) | (3 << 20),
>> +           DDR2ODTCFG);
>> +
>> +    /* TODO: resolve differences in NXTDATRQDLY, NXDATAVDLY and RDATENDLY
>> */ +    writel(/*(WL - 1)*/2 | (/*((RL + 1) & 0x0F)*/4  << 4) |
>> +           (/*(RL - 1)*/2 << 16) |
>> +           (MAX_BURST << 24) | (7 << 28) | (BIG_ENDIAN << 31),
>> +           DDR2XFERCFG);
> Fixme please ;-)

ack.

>> +    /* DRAM Initialization */
>> +    /* bring CKE high after reset and wait 400 nsec */
>> +    writel(IDLE_NOP, DDR2CMD10);
>> +    writel((0x00 | (0x00 << 8) | (hc_clk_dly(400000) << 11)),
>> +           DDR2CMD20);
>> +
>> +    /* issue precharge all command */
>> +    writel(PRECH_ALL_CMD, DDR2CMD10 + 0x04);
>> +    writel((0x04 | (0x00 << 8) | (hc_clk_dly(tRP + CLK_PERIOD) << 11)),
>> +           DDR2CMD20 + 0x04);
>> +
>> +    /* initialize EMR2 */
>> +    writel(LOAD_MODE_CMD, DDR2CMD10 + 0x08);
>> +    writel((0x00 | (0x02 << 8) | (hc_clk_dly(tMRD * CLK_PERIOD) << 11)),
>> +           DDR2CMD20 + 0x08);
> [...]
>
>> +    writel(0x1B, DDR2CMDISSUE);
>> +    writel(0x01, DDR2MEMCON);
>> +
>> +    while (readl(DDR2CMDISSUE) & 0x10)
>> +        ;
> Use the wait_for_bit() function here and for the other unbounded while loop 
> below. This will add timeout to the wait, so your code will not get stuck in
> an endless loop.

ack.

>> +    writel(0x03, DDR2MEMCON);
>> +
>> +    /* SCL Start */
>> +    writel(SCL_START | SCL_EN, DDR2SCLSTART);
>> +
>> +    /* Wait for SCL byte to pass */
>> +    while ((readl(DDR2SCLSTART) & SCL_LUBPASS) != SCL_LUBPASS)
>> +        ;
>> +}
>> diff --git a/board/microchip/pic32mzda/ddr.h
>> b/board/microchip/pic32mzda/ddr.h new file mode 100644
>> index 0000000..7828169
>> --- /dev/null
>> +++ b/board/microchip/pic32mzda/ddr.h
>> @@ -0,0 +1,46 @@
>> +/*
>> + * (c) 2015 Purna Chandra Mandal purna.mandal at microchip.com>
>> + *
>> + * SPDX-License-Identifier:    GPL-2.0+
>> + *
>> + */
>> +
>> +#ifndef __PIC32MZDA_DDR_H
>> +#define __PIC32MZDA_DDR_H
>> +
>> +#define DDR2TSEL    (PIC32_DDR2C_BASE + 0x00) /* ARB_AGENT_SEL       */
>> +#define DDR2MINLIM    (PIC32_DDR2C_BASE + 0x04) /* MIN_LIMIT           */
> Nuke the trailing indent in the comment please.

ack.

>> +#define DDR2REQPRD    (PIC32_DDR2C_BASE + 0x08) /* RQST_PERIOD         */
>> +#define DDR2MINCMD    (PIC32_DDR2C_BASE + 0x0c) /* MIN_CMD_ACPT        */
>> +#define DDR2MEMCON    (PIC32_DDR2C_BASE + 0x10) /* MEM_START           */
>> +#define DDR2MEMCFG0    (PIC32_DDR2C_BASE + 0x14) /* MEM_CONFIG_1        */
>> +#define DDR2MEMCFG1    (PIC32_DDR2C_BASE + 0x18) /* MEM_CONFIG_2        */
>> +#define DDR2MEMCFG2    (PIC32_DDR2C_BASE + 0x1c) /* MEM_CONFIG_3        */
>> +#define DDR2MEMCFG3    (PIC32_DDR2C_BASE + 0x20) /* MEM_CONFIG_4        */
>> +#define DDR2MEMCFG4    (PIC32_DDR2C_BASE + 0x24) /* MEM_CONFIG_5        */
>> +#define DDR2REFCFG    (PIC32_DDR2C_BASE + 0x28) /* REF_CONFIG          */
>> +#define DDR2PWRCFG    (PIC32_DDR2C_BASE + 0x2c) /* PWR_SAVE_ECC_CONFIG */
>> +#define DDR2DLYCFG0    (PIC32_DDR2C_BASE + 0x30) /* DLY_CONFIG1         */
> [...]