[PATCH 1/1] at91: fix reset
Jean-Christophe PLAGNIOL-VILLARD
plagnioj at jcrosoft.com
Tue Dec 13 11:37:25 EST 2011
on at91sam9 you need to shutdown the sdram/ddr controler before reseting
when you boot from nand
Signed-off-by: Jean-Christophe PLAGNIOL-VILLARD <plagnioj at jcrosoft.com>
---
arch/arm/mach-at91/Kconfig | 12 ++
arch/arm/mach-at91/Makefile | 3 +
arch/arm/mach-at91/at91sam926x_time.c | 14 --
arch/arm/mach-at91/at91sam9_reset.S | 43 +++++++
arch/arm/mach-at91/at91sam9g45_reset.S | 40 ++++++
arch/arm/mach-at91/include/mach/at91sam9_ddrsdr.h | 134 +++++++++++++++++++++
6 files changed, 232 insertions(+), 14 deletions(-)
create mode 100644 arch/arm/mach-at91/at91sam9_reset.S
create mode 100644 arch/arm/mach-at91/at91sam9g45_reset.S
create mode 100644 arch/arm/mach-at91/include/mach/at91sam9_ddrsdr.h
diff --git a/arch/arm/mach-at91/Kconfig b/arch/arm/mach-at91/Kconfig
index c53ade9..8f3b8ce 100644
--- a/arch/arm/mach-at91/Kconfig
+++ b/arch/arm/mach-at91/Kconfig
@@ -28,6 +28,12 @@ config BOARDINFO
config HAVE_NAND_ATMEL_BUSWIDTH_16
bool
+config AT91SAM9_RESET
+ bool
+
+config AT91SAM9G45_RESET
+ bool
+
comment "Atmel AT91 System-on-Chip"
choice
@@ -45,29 +51,35 @@ config ARCH_AT91SAM9260
bool "AT91SAM9260"
select CPU_ARM926T
select HAS_MACB
+ select AT91SAM9_RESET
config ARCH_AT91SAM9261
bool "AT91SAM9261"
select CPU_ARM926T
+ select AT91SAM9_RESET
config ARCH_AT91SAM9263
bool "AT91SAM9263"
select CPU_ARM926T
select HAS_MACB
+ select AT91SAM9_RESET
config ARCH_AT91SAM9G10
bool "AT91SAM9G10"
select CPU_ARM926T
+ select AT91SAM9_RESET
config ARCH_AT91SAM9G20
bool "AT91SAM9G20"
select CPU_ARM926T
select HAS_MACB
+ select AT91SAM9_RESET
config ARCH_AT91SAM9G45
bool "AT91SAM9G45 or AT91SAM9M10"
select CPU_ARM926T
select HAS_MACB
+ select AT91SAM9G45_RESET
endchoice
diff --git a/arch/arm/mach-at91/Makefile b/arch/arm/mach-at91/Makefile
index e72f409..219f75c 100644
--- a/arch/arm/mach-at91/Makefile
+++ b/arch/arm/mach-at91/Makefile
@@ -4,6 +4,9 @@ lowlevel_init-y = at91sam926x_lowlevel_init.o
lowlevel_init-$(CONFIG_ARCH_AT91RM9200) = at91rm9200_lowlevel_init.o
obj-$(CONFIG_MACH_DO_LOWLEVEL_INIT) += $(lowlevel_init-y)
+obj-$(CONFIG_AT91SAM9_RESET) += at91sam9_reset.o
+obj-$(CONFIG_AT91SAM9G45_RESET) += at91sam9g45_reset.o
+
# CPU-specific support
obj-$(CONFIG_ARCH_AT91RM9200) += at91rm9200.o at91rm9200_time.o at91rm9200_devices.o
obj-$(CONFIG_ARCH_AT91SAM9260) += at91sam9260.o at91sam926x_time.o at91sam9260_devices.o sam9_smc.o
diff --git a/arch/arm/mach-at91/at91sam926x_time.c b/arch/arm/mach-at91/at91sam926x_time.c
index 7ca2ef4..b95cef3 100644
--- a/arch/arm/mach-at91/at91sam926x_time.c
+++ b/arch/arm/mach-at91/at91sam926x_time.c
@@ -69,17 +69,3 @@ static int clocksource_init (void)
}
core_initcall(clocksource_init);
-
-/*
- * Reset the cpu through the reset controller
- */
-void __noreturn reset_cpu (unsigned long addr)
-{
- at91_sys_write(AT91_RSTC_CR, AT91_RSTC_KEY |
- AT91_RSTC_PROCRST |
- AT91_RSTC_PERRST);
-
- /* Not reached */
- while (1);
-}
-EXPORT_SYMBOL(reset_cpu);
diff --git a/arch/arm/mach-at91/at91sam9_reset.S b/arch/arm/mach-at91/at91sam9_reset.S
new file mode 100644
index 0000000..9a0bc0d
--- /dev/null
+++ b/arch/arm/mach-at91/at91sam9_reset.S
@@ -0,0 +1,43 @@
+/*
+ * reset AT91SAM9G20 as per errata
+ *
+ * (C) BitBox Ltd 2010
+ *
+ * unless the SDRAM is cleanly shutdown before we hit the
+ * reset register it can be left driving the data bus and
+ * killing the chance of a subsequent boot from NAND
+ *
+ * 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.
+ */
+
+#include <linux/linkage.h>
+#include <mach/hardware.h>
+#include <mach/at91sam9_sdramc.h>
+#include <mach/at91_rstc.h>
+
+ .arm
+
+ .globl reset_cpu
+
+reset_cpu: ldr r0, .at91_va_base_sdramc @ preload constants
+ ldr r1, .at91_va_base_rstc_cr
+
+ mov r2, #1
+ mov r3, #AT91_SDRAMC_LPCB_POWER_DOWN
+ ldr r4, =AT91_RSTC_KEY | AT91_RSTC_PERRST | AT91_RSTC_PROCRST
+
+ .balign 32 @ align to cache line
+
+ str r2, [r0, #AT91_SDRAMC_TR - AT91_SDRAMC] @ disable SDRAM access
+ str r3, [r0, #AT91_SDRAMC_LPR - AT91_SDRAMC] @ power down SDRAM
+ str r4, [r1] @ reset processor
+
+ b .
+
+.at91_va_base_sdramc:
+ .word AT91_BASE_SYS + AT91_SDRAMC
+.at91_va_base_rstc_cr:
+ .word AT91_BASE_SYS + AT91_RSTC_CR
diff --git a/arch/arm/mach-at91/at91sam9g45_reset.S b/arch/arm/mach-at91/at91sam9g45_reset.S
new file mode 100644
index 0000000..e70d733
--- /dev/null
+++ b/arch/arm/mach-at91/at91sam9g45_reset.S
@@ -0,0 +1,40 @@
+/*
+ * reset AT91SAM9G45 as per errata
+ *
+ * Copyright (C) 2011 Jean-Christophe PLAGNIOL-VILLARD <plagnioj at jcosoft.com>
+ *
+ * unless the SDRAM is cleanly shutdown before we hit the
+ * reset register it can be left driving the data bus and
+ * killing the chance of a subsequent boot from NAND
+ *
+ * GPLv2 Only
+ */
+
+#include <linux/linkage.h>
+#include <mach/hardware.h>
+#include <mach/at91sam9_ddrsdr.h>
+#include <mach/at91_rstc.h>
+
+ .arm
+
+ .globl reset_cpu
+
+reset_cpu: ldr r0, .at91_va_base_sdramc @ preload constants
+ ldr r1, .at91_va_base_rstc_cr
+
+ mov r2, #1
+ mov r3, #AT91_DDRSDRC_LPCB_POWER_DOWN
+ ldr r4, =AT91_RSTC_KEY | AT91_RSTC_PERRST | AT91_RSTC_PROCRST
+
+ .balign 32 @ align to cache line
+
+ str r2, [r0, #AT91_DDRSDRC_RTR] @ disable DDR0 access
+ str r3, [r0, #AT91_DDRSDRC_LPR] @ power down DDR0
+ str r4, [r1] @ reset processor
+
+ b .
+
+.at91_va_base_sdramc:
+ .word AT91_BASE_SYS + AT91_DDRSDRC0
+.at91_va_base_rstc_cr:
+ .word AT91_BASE_SYS + AT91_RSTC_CR
diff --git a/arch/arm/mach-at91/include/mach/at91sam9_ddrsdr.h b/arch/arm/mach-at91/include/mach/at91sam9_ddrsdr.h
new file mode 100644
index 0000000..070f730
--- /dev/null
+++ b/arch/arm/mach-at91/include/mach/at91sam9_ddrsdr.h
@@ -0,0 +1,134 @@
+/*
+ * Header file for the Atmel DDR/SDR SDRAM Controller
+ *
+ * Copyright (C) 2010 Atmel Corporation
+ * Nicolas Ferre <nicolas.ferre at atmel.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.
+ */
+#ifndef AT91SAM9_DDRSDR_H
+#define AT91SAM9_DDRSDR_H
+
+#define AT91_DDRSDRC_MR 0x00 /* Mode Register */
+#define AT91_DDRSDRC_MODE (0x7 << 0) /* Command Mode */
+#define AT91_DDRSDRC_MODE_NORMAL 0
+#define AT91_DDRSDRC_MODE_NOP 1
+#define AT91_DDRSDRC_MODE_PRECHARGE 2
+#define AT91_DDRSDRC_MODE_LMR 3
+#define AT91_DDRSDRC_MODE_REFRESH 4
+#define AT91_DDRSDRC_MODE_EXT_LMR 5
+#define AT91_DDRSDRC_MODE_DEEP 6
+
+#define AT91_DDRSDRC_RTR 0x04 /* Refresh Timer Register */
+#define AT91_DDRSDRC_COUNT (0xfff << 0) /* Refresh Timer Counter */
+
+#define AT91_DDRSDRC_CR 0x08 /* Configuration Register */
+#define AT91_DDRSDRC_NC (3 << 0) /* Number of Column Bits */
+#define AT91_DDRSDRC_NC_SDR8 (0 << 0)
+#define AT91_DDRSDRC_NC_SDR9 (1 << 0)
+#define AT91_DDRSDRC_NC_SDR10 (2 << 0)
+#define AT91_DDRSDRC_NC_SDR11 (3 << 0)
+#define AT91_DDRSDRC_NC_DDR9 (0 << 0)
+#define AT91_DDRSDRC_NC_DDR10 (1 << 0)
+#define AT91_DDRSDRC_NC_DDR11 (2 << 0)
+#define AT91_DDRSDRC_NC_DDR12 (3 << 0)
+#define AT91_DDRSDRC_NR (3 << 2) /* Number of Row Bits */
+#define AT91_DDRSDRC_NR_11 (0 << 2)
+#define AT91_DDRSDRC_NR_12 (1 << 2)
+#define AT91_DDRSDRC_NR_13 (2 << 2)
+#define AT91_DDRSDRC_NR_14 (3 << 2)
+#define AT91_DDRSDRC_CAS (7 << 4) /* CAS Latency */
+#define AT91_DDRSDRC_CAS_2 (2 << 4)
+#define AT91_DDRSDRC_CAS_3 (3 << 4)
+#define AT91_DDRSDRC_CAS_25 (6 << 4)
+#define AT91_DDRSDRC_RST_DLL (1 << 7) /* Reset DLL */
+#define AT91_DDRSDRC_DICDS (1 << 8) /* Output impedance control */
+#define AT91_DDRSDRC_DIS_DLL (1 << 9) /* Disable DLL [SAM9 Only] */
+#define AT91_DDRSDRC_OCD (1 << 12) /* Off-Chip Driver [SAM9 Only] */
+#define AT91_DDRSDRC_DQMS (1 << 16) /* Mask Data is Shared [SAM9 Only] */
+#define AT91_DDRSDRC_ACTBST (1 << 18) /* Active Bank X to Burst Stop Read Access Bank Y [SAM9 Only] */
+
+#define AT91_DDRSDRC_T0PR 0x0C /* Timing 0 Register */
+#define AT91_DDRSDRC_TRAS (0xf << 0) /* Active to Precharge delay */
+#define AT91_DDRSDRC_TRCD (0xf << 4) /* Row to Column delay */
+#define AT91_DDRSDRC_TWR (0xf << 8) /* Write recovery delay */
+#define AT91_DDRSDRC_TRC (0xf << 12) /* Row cycle delay */
+#define AT91_DDRSDRC_TRP (0xf << 16) /* Row precharge delay */
+#define AT91_DDRSDRC_TRRD (0xf << 20) /* Active BankA to BankB */
+#define AT91_DDRSDRC_TWTR (0x7 << 24) /* Internal Write to Read delay */
+#define AT91CAP9_DDRSDRC_TWTR (1 << 24) /* Internal Write to Read delay */
+#define AT91_DDRSDRC_RED_WRRD (0x1 << 27) /* Reduce Write to Read Delay [SAM9 Only] */
+#define AT91_DDRSDRC_TMRD (0xf << 28) /* Load mode to active/refresh delay */
+
+#define AT91_DDRSDRC_T1PR 0x10 /* Timing 1 Register */
+#define AT91_DDRSDRC_TRFC (0x1f << 0) /* Row Cycle Delay */
+#define AT91_DDRSDRC_TXSNR (0xff << 8) /* Exit self-refresh to non-read */
+#define AT91_DDRSDRC_TXSRD (0xff << 16) /* Exit self-refresh to read */
+#define AT91_DDRSDRC_TXP (0xf << 24) /* Exit power-down delay */
+
+#define AT91_DDRSDRC_T2PR 0x14 /* Timing 2 Register [SAM9 Only] */
+#define AT91_DDRSDRC_TXARD (0xf << 0) /* Exit active power down delay to read command in mode "Fast Exit" */
+#define AT91_DDRSDRC_TXARDS (0xf << 4) /* Exit active power down delay to read command in mode "Slow Exit" */
+#define AT91_DDRSDRC_TRPA (0xf << 8) /* Row Precharge All delay */
+#define AT91_DDRSDRC_TRTP (0x7 << 12) /* Read to Precharge delay */
+
+#define AT91_DDRSDRC_LPR 0x1C /* Low Power Register */
+#define AT91CAP9_DDRSDRC_LPR 0x18 /* Low Power Register */
+#define AT91_DDRSDRC_LPCB (3 << 0) /* Low-power Configurations */
+#define AT91_DDRSDRC_LPCB_DISABLE 0
+#define AT91_DDRSDRC_LPCB_SELF_REFRESH 1
+#define AT91_DDRSDRC_LPCB_POWER_DOWN 2
+#define AT91_DDRSDRC_LPCB_DEEP_POWER_DOWN 3
+#define AT91_DDRSDRC_CLKFR (1 << 2) /* Clock Frozen */
+#define AT91_DDRSDRC_PASR (7 << 4) /* Partial Array Self Refresh */
+#define AT91_DDRSDRC_TCSR (3 << 8) /* Temperature Compensated Self Refresh */
+#define AT91_DDRSDRC_DS (3 << 10) /* Drive Strength */
+#define AT91_DDRSDRC_TIMEOUT (3 << 12) /* Time to define when Low Power Mode is enabled */
+#define AT91_DDRSDRC_TIMEOUT_0_CLK_CYCLES (0 << 12)
+#define AT91_DDRSDRC_TIMEOUT_64_CLK_CYCLES (1 << 12)
+#define AT91_DDRSDRC_TIMEOUT_128_CLK_CYCLES (2 << 12)
+#define AT91_DDRSDRC_APDE (1 << 16) /* Active power down exit time */
+#define AT91_DDRSDRC_UPD_MR (3 << 20) /* Update load mode register and extended mode register */
+
+#define AT91_DDRSDRC_MDR 0x20 /* Memory Device Register */
+#define AT91CAP9_DDRSDRC_MDR 0x1C /* Memory Device Register */
+#define AT91_DDRSDRC_MD (3 << 0) /* Memory Device Type */
+#define AT91_DDRSDRC_MD_SDR 0
+#define AT91_DDRSDRC_MD_LOW_POWER_SDR 1
+#define AT91CAP9_DDRSDRC_MD_DDR 2
+#define AT91_DDRSDRC_MD_LOW_POWER_DDR 3
+#define AT91_DDRSDRC_MD_DDR2 6 /* [SAM9 Only] */
+#define AT91_DDRSDRC_DBW (1 << 4) /* Data Bus Width */
+#define AT91_DDRSDRC_DBW_32BITS (0 << 4)
+#define AT91_DDRSDRC_DBW_16BITS (1 << 4)
+
+#define AT91_DDRSDRC_DLL 0x24 /* DLL Information Register */
+#define AT91CAP9_DDRSDRC_DLL 0x20 /* DLL Information Register */
+#define AT91_DDRSDRC_MDINC (1 << 0) /* Master Delay increment */
+#define AT91_DDRSDRC_MDDEC (1 << 1) /* Master Delay decrement */
+#define AT91_DDRSDRC_MDOVF (1 << 2) /* Master Delay Overflow */
+#define AT91CAP9_DDRSDRC_SDCOVF (1 << 3) /* Slave Delay Correction Overflow */
+#define AT91CAP9_DDRSDRC_SDCUDF (1 << 4) /* Slave Delay Correction Underflow */
+#define AT91CAP9_DDRSDRC_SDERF (1 << 5) /* Slave Delay Correction error */
+#define AT91_DDRSDRC_MDVAL (0xff << 8) /* Master Delay value */
+#define AT91CAP9_DDRSDRC_SDVAL (0xff << 16) /* Slave Delay value */
+#define AT91CAP9_DDRSDRC_SDCVAL (0xff << 24) /* Slave Delay Correction value */
+
+#define AT91_DDRSDRC_HS 0x2C /* High Speed Register [SAM9 Only] */
+#define AT91_DDRSDRC_DIS_ATCP_RD (1 << 2) /* Anticip read access is disabled */
+
+#define AT91_DDRSDRC_DELAY(n) (0x30 + (0x4 * (n))) /* Delay I/O Register n */
+
+#define AT91_DDRSDRC_WPMR 0xE4 /* Write Protect Mode Register [SAM9 Only] */
+#define AT91_DDRSDRC_WP (1 << 0) /* Write protect enable */
+#define AT91_DDRSDRC_WPKEY (0xffffff << 8) /* Write protect key */
+#define AT91_DDRSDRC_KEY (0x444452 << 8) /* Write protect key = "DDR" */
+
+#define AT91_DDRSDRC_WPSR 0xE8 /* Write Protect Status Register [SAM9 Only] */
+#define AT91_DDRSDRC_WPVS (1 << 0) /* Write protect violation status */
+#define AT91_DDRSDRC_WPVSRC (0xffff << 8) /* Write protect violation source */
+
+#endif
--
1.7.7
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