[U-Boot] [PATCH] ppc4xx: Add SDRAM detection for PMC440 boards

Matthias Fuchs
2009-09-29T15:30:38Z

This patch adds support to detect the amount of DDR2 SDRAM
on PMC440 modules. Detection is done by probing through
a list of available and supported hardware configurations
from 256MB to 1GByte.

The static TLB entry is replaced by dynamically created entries.

Signed-off-by: Matthias Fuchs <matthias.fuchs@esd.eu>
---
board/esd/pmc440/init.S | 13 +++----
board/esd/pmc440/sdram.c | 83 ++++++++++++++++++++++++++++++++-------------
include/configs/PMC440.h | 1 -
3 files changed, 64 insertions(+), 33 deletions(-)

diff --git a/board/esd/pmc440/init.S b/board/esd/pmc440/init.S
index 26a8282..da5bd8d 100644
--- a/board/esd/pmc440/init.S
+++ b/board/esd/pmc440/init.S
@@ -23,7 +23,7 @@
#include <asm-ppc/mmu.h>
#include <config.h>

-/**************************************************************************
+/*
* TLB TABLE
*
* This table is used by the cpu boot code to setup the initial tlb
@@ -32,7 +32,7 @@
*
* Pointer to the table is returned in r1
*
- *************************************************************************/
+ */
.section .bootpg,"ax"
.globl tlbtab

@@ -49,12 +49,9 @@ tlbtab:
tlbentry( CONFIG_SYS_NAND_BOOT_SPL_SRC, SZ_4K, CONFIG_SYS_NAND_BOOT_SPL_SRC, 1, AC_R|AC_W|AC_X|SA_G )
#endif

- /* TLB-entry for DDR SDRAM (Up to 2GB) */
-#ifdef CONFIG_4xx_DCACHE
- tlbentry( CONFIG_SYS_SDRAM_BASE, SZ_256M, CONFIG_SYS_SDRAM_BASE, 0, AC_R|AC_W|AC_X|SA_G)
-#else
- tlbentry( CONFIG_SYS_SDRAM_BASE, SZ_256M, CONFIG_SYS_SDRAM_BASE, 0, AC_R|AC_W|AC_X|SA_G|SA_I )
-#endif
+ /* TLB entries for DDR2 SDRAM are generated dynamically */
+
+ /* TLB-entry for DDR SDRAM are created dynamically from initdram() */

#ifdef CONFIG_SYS_INIT_RAM_DCACHE
/* TLB-entry for init-ram in dcache (SA_I must be turned off!) */
diff --git a/board/esd/pmc440/sdram.c b/board/esd/pmc440/sdram.c
index bb46ecc..826050c 100644
--- a/board/esd/pmc440/sdram.c
+++ b/board/esd/pmc440/sdram.c
@@ -1,4 +1,7 @@
/*
+ * (C) Copyright 2009
+ * Matthias Fuchs, esd gmbh, matthias.fuchs at esd.eu
+ *
* (C) Copyright 2006
* Sylvie Gohl, AMCC/IBM, gohl.sylvie at fr.ibm.com
* Jacqueline Pira-Ferriol, AMCC/IBM, jpira-ferriol at fr.ibm.com
@@ -31,33 +34,30 @@
#include <common.h>
#include <asm/processor.h>
#include <asm/io.h>
+#include <asm/mmu.h>
#include <ppc440.h>

extern int denali_wait_for_dlllock(void);
extern void denali_core_search_data_eye(void);

+struct sdram_conf_s {
+ ulong size;
+ int rows;
+ int banks;
+};

-#if defined(CONFIG_NAND_SPL)
-/* Using cpu/ppc4xx/speed.c to calculate the bus frequency is too big
- * for the 4k NAND boot image so define bus_frequency to 133MHz here
- * which is save for the refresh counter setup.
- */
-#define get_bus_freq(val) 133000000
-#endif
+struct sdram_conf_s sdram_conf[] = {
+ {(1024 << 20), 14, 8}, /* 1GByte: 4x2GBit, 14x10, 8 banks */
+ {(512 << 20), 13, 8}, /* 512MByte: 4x1GBit, 13x10, 8 banks */
+ {(256 << 20), 13, 4}, /* 256MByte: 4x512MBit, 13x10, 4 banks */
+};

-/*************************************************************************
- *
+/*
* initdram -- 440EPx's DDR controller is a DENALI Core
- *
- ************************************************************************/
-phys_size_t initdram (int board_type)
+ */
+int initdram_by_rb(int rows, int banks)
{
-#if !defined(CONFIG_NAND_U_BOOT) || defined(CONFIG_NAND_SPL)
-#if !defined(CONFIG_NAND_SPL)
ulong speed = get_bus_freq(0);
-#else
- ulong speed = 133333333; /* 133MHz is on the safe side */
-#endif

mtsdram(DDR0_02, 0x00000000);

@@ -89,21 +89,25 @@ phys_size_t initdram (int board_type)
mtsdram(DDR0_27, 0x0000682B);
mtsdram(DDR0_28, 0x00000000);
mtsdram(DDR0_31, 0x00000000);
- mtsdram(DDR0_42, 0x01000006);
- mtsdram(DDR0_43, 0x030A0200);
+
+ mtsdram(DDR0_42,
+ DDR0_42_ADDR_PINS_DECODE(14 - rows) |
+ 0x00000006);
+ mtsdram(DDR0_43,
+ DDR0_43_EIGHT_BANK_MODE_ENCODE(8 == banks ? 1 : 0) |
+ 0x030A0200);
+
mtsdram(DDR0_44, 0x00000003);
mtsdram(DDR0_02, 0x00000001);

denali_wait_for_dlllock();
-#endif /* #ifndef CONFIG_NAND_U_BOOT */

#ifdef CONFIG_DDR_DATA_EYE
- /* -----------------------------------------------------------+
+ /*
* Perform data eye search if requested.
- * ----------------------------------------------------------*/
+ */
denali_core_search_data_eye();
#endif
-
/*
* Clear possible errors resulting from data-eye-search.
* If not done, then we could get an interrupt later on when
@@ -111,5 +115,36 @@ phys_size_t initdram (int board_type)
*/
set_mcsr(get_mcsr());

- return (CONFIG_SYS_MBYTES_SDRAM << 20);
+ return 0;
+}
+
+
+phys_size_t initdram (int board_type)
+{
+ phys_size_t size;
+ int n;
+
+ /* go through supported memory configurations */
+ for (n = 0; n < ARRAY_SIZE(sdram_conf); n++) {
+ size = sdram_conf[n].size;
+
+ /* program TLB entries */
+ program_tlb(0, CONFIG_SYS_SDRAM_BASE, size,
+ TLB_WORD2_I_ENABLE);
+
+ /*
+ * setup denali core
+ */
+ initdram_by_rb(sdram_conf[n].rows,
+ sdram_conf[n].banks);
+
+ /* check for suitable configuration */
+ if (get_ram_size(CONFIG_SYS_SDRAM_BASE, size) == size)
+ return size;
+
+ /* delete TLB entries */
+ remove_tlb(CONFIG_SYS_SDRAM_BASE, size);
+ }
+
+ return 0;
}
diff --git a/include/configs/PMC440.h b/include/configs/PMC440.h
index 012ae79..d6e2f6b 100644
--- a/include/configs/PMC440.h
+++ b/include/configs/PMC440.h
@@ -215,7 +215,6 @@
/*-----------------------------------------------------------------------
* DDR SDRAM
*----------------------------------------------------------------------*/
-#define CONFIG_SYS_MBYTES_SDRAM (256) /* 256MB */
#if !defined(CONFIG_NAND_U_BOOT) && !defined(CONFIG_NAND_SPL)
#define CONFIG_DDR_DATA_EYE /* use DDR2 optimization */
#endif
--
1.6.1