u-boot/arch/arm/mach-socfpga/freeze_controller.c
Marek Vasut a8535c306c arm: socfpga: Fix delay in freeze controller
Based on observation, this udelay(20) was apparently too high and caused
subsequent failure to calibrate DDR when U-Boot was compiled with certain
toolchains. Lowering this delay fixed the problem.

Instead of permanently lowering the delay, calculate the correct delay
based on the original comment, that is, obtain EOSC1 frequency and use
it to calculate the precise delay.

Signed-off-by: Marek Vasut <marex@denx.de>
2015-08-23 11:56:19 +02:00

211 lines
5.6 KiB
C

/*
* Copyright (C) 2013 Altera Corporation <www.altera.com>
*
* SPDX-License-Identifier: GPL-2.0+
*/
#include <common.h>
#include <asm/io.h>
#include <asm/arch/clock_manager.h>
#include <asm/arch/freeze_controller.h>
#include <asm/errno.h>
DECLARE_GLOBAL_DATA_PTR;
static const struct socfpga_freeze_controller *freeze_controller_base =
(void *)(SOCFPGA_SYSMGR_ADDRESS + SYSMGR_FRZCTRL_ADDRESS);
/*
* Default state from cold reset is FREEZE_ALL; the global
* flag is set to TRUE to indicate the IO banks are frozen
*/
static uint32_t frzctrl_channel_freeze[FREEZE_CHANNEL_NUM]
= { FREEZE_CTRL_FROZEN, FREEZE_CTRL_FROZEN,
FREEZE_CTRL_FROZEN, FREEZE_CTRL_FROZEN};
/* Freeze HPS IOs */
void sys_mgr_frzctrl_freeze_req(void)
{
u32 ioctrl_reg_offset;
u32 reg_value;
u32 reg_cfg_mask;
u32 channel_id;
/* select software FSM */
writel(SYSMGR_FRZCTRL_SRC_VIO1_ENUM_SW, &freeze_controller_base->src);
/* Freeze channel 0 to 2 */
for (channel_id = 0; channel_id <= 2; channel_id++) {
ioctrl_reg_offset = (u32)(
&freeze_controller_base->vioctrl + channel_id);
/*
* Assert active low enrnsl, plniotri
* and niotri signals
*/
reg_cfg_mask =
SYSMGR_FRZCTRL_VIOCTRL_SLEW_MASK
| SYSMGR_FRZCTRL_VIOCTRL_WKPULLUP_MASK
| SYSMGR_FRZCTRL_VIOCTRL_TRISTATE_MASK;
clrbits_le32(ioctrl_reg_offset, reg_cfg_mask);
/*
* Note: Delay for 20ns at min
* Assert active low bhniotri signal and de-assert
* active high csrdone
*/
reg_cfg_mask
= SYSMGR_FRZCTRL_VIOCTRL_BUSHOLD_MASK
| SYSMGR_FRZCTRL_VIOCTRL_CFG_MASK;
clrbits_le32(ioctrl_reg_offset, reg_cfg_mask);
/* Set global flag to indicate channel is frozen */
frzctrl_channel_freeze[channel_id] = FREEZE_CTRL_FROZEN;
}
/* Freeze channel 3 */
/*
* Assert active low enrnsl, plniotri and
* niotri signals
*/
reg_cfg_mask
= SYSMGR_FRZCTRL_HIOCTRL_SLEW_MASK
| SYSMGR_FRZCTRL_HIOCTRL_WKPULLUP_MASK
| SYSMGR_FRZCTRL_HIOCTRL_TRISTATE_MASK;
clrbits_le32(&freeze_controller_base->hioctrl, reg_cfg_mask);
/*
* assert active low bhniotri & nfrzdrv signals,
* de-assert active high csrdone and assert
* active high frzreg and nfrzdrv signals
*/
reg_value = readl(&freeze_controller_base->hioctrl);
reg_cfg_mask
= SYSMGR_FRZCTRL_HIOCTRL_BUSHOLD_MASK
| SYSMGR_FRZCTRL_HIOCTRL_CFG_MASK;
reg_value
= (reg_value & ~reg_cfg_mask)
| SYSMGR_FRZCTRL_HIOCTRL_REGRST_MASK
| SYSMGR_FRZCTRL_HIOCTRL_OCTRST_MASK;
writel(reg_value, &freeze_controller_base->hioctrl);
/*
* assert active high reinit signal and de-assert
* active high pllbiasen signals
*/
reg_value = readl(&freeze_controller_base->hioctrl);
reg_value
= (reg_value &
~SYSMGR_FRZCTRL_HIOCTRL_OCT_CFGEN_CALSTART_MASK)
| SYSMGR_FRZCTRL_HIOCTRL_DLLRST_MASK;
writel(reg_value, &freeze_controller_base->hioctrl);
/* Set global flag to indicate channel is frozen */
frzctrl_channel_freeze[channel_id] = FREEZE_CTRL_FROZEN;
}
/* Unfreeze/Thaw HPS IOs */
void sys_mgr_frzctrl_thaw_req(void)
{
u32 ioctrl_reg_offset;
u32 reg_cfg_mask;
u32 reg_value;
u32 channel_id;
unsigned long eosc1_freq;
/* select software FSM */
writel(SYSMGR_FRZCTRL_SRC_VIO1_ENUM_SW, &freeze_controller_base->src);
/* Thaw channel 0 to 2 */
for (channel_id = 0; channel_id <= 2; channel_id++) {
ioctrl_reg_offset
= (u32)(&freeze_controller_base->vioctrl + channel_id);
/*
* Assert active low bhniotri signal and
* de-assert active high csrdone
*/
reg_cfg_mask
= SYSMGR_FRZCTRL_VIOCTRL_BUSHOLD_MASK
| SYSMGR_FRZCTRL_VIOCTRL_CFG_MASK;
setbits_le32(ioctrl_reg_offset, reg_cfg_mask);
/*
* Note: Delay for 20ns at min
* de-assert active low plniotri and niotri signals
*/
reg_cfg_mask
= SYSMGR_FRZCTRL_VIOCTRL_WKPULLUP_MASK
| SYSMGR_FRZCTRL_VIOCTRL_TRISTATE_MASK;
setbits_le32(ioctrl_reg_offset, reg_cfg_mask);
/*
* Note: Delay for 20ns at min
* de-assert active low enrnsl signal
*/
setbits_le32(ioctrl_reg_offset,
SYSMGR_FRZCTRL_VIOCTRL_SLEW_MASK);
/* Set global flag to indicate channel is thawed */
frzctrl_channel_freeze[channel_id] = FREEZE_CTRL_THAWED;
}
/* Thaw channel 3 */
/* de-assert active high reinit signal */
clrbits_le32(&freeze_controller_base->hioctrl,
SYSMGR_FRZCTRL_HIOCTRL_DLLRST_MASK);
/*
* Note: Delay for 40ns at min
* assert active high pllbiasen signals
*/
setbits_le32(&freeze_controller_base->hioctrl,
SYSMGR_FRZCTRL_HIOCTRL_OCT_CFGEN_CALSTART_MASK);
/* Delay 1000 intosc cycles. The intosc is based on eosc1. */
eosc1_freq = cm_get_osc_clk_hz(1) / 1000; /* kHz */
udelay(DIV_ROUND_UP(1000000, eosc1_freq));
/*
* de-assert active low bhniotri signals,
* assert active high csrdone and nfrzdrv signal
*/
reg_value = readl(&freeze_controller_base->hioctrl);
reg_value = (reg_value
| SYSMGR_FRZCTRL_HIOCTRL_BUSHOLD_MASK
| SYSMGR_FRZCTRL_HIOCTRL_CFG_MASK)
& ~SYSMGR_FRZCTRL_HIOCTRL_OCTRST_MASK;
writel(reg_value, &freeze_controller_base->hioctrl);
/*
* Delay 33 intosc
* Use worst case which is fatest eosc1=50MHz, delay required
* is 1/50MHz * 33 = 660ns ~= 1us
*/
udelay(1);
/* de-assert active low plniotri and niotri signals */
reg_cfg_mask
= SYSMGR_FRZCTRL_HIOCTRL_WKPULLUP_MASK
| SYSMGR_FRZCTRL_HIOCTRL_TRISTATE_MASK;
setbits_le32(&freeze_controller_base->hioctrl, reg_cfg_mask);
/*
* Note: Delay for 40ns at min
* de-assert active high frzreg signal
*/
clrbits_le32(&freeze_controller_base->hioctrl,
SYSMGR_FRZCTRL_HIOCTRL_REGRST_MASK);
/*
* Note: Delay for 40ns at min
* de-assert active low enrnsl signal
*/
setbits_le32(&freeze_controller_base->hioctrl,
SYSMGR_FRZCTRL_HIOCTRL_SLEW_MASK);
/* Set global flag to indicate channel is thawed */
frzctrl_channel_freeze[channel_id] = FREEZE_CTRL_THAWED;
}