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linuxdebug/arch/m68k/coldfire/m53xx.c

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// SPDX-License-Identifier: GPL-2.0-or-later
/***************************************************************************/
/*
* m53xx.c -- platform support for ColdFire 53xx based boards
*
* Copyright (C) 1999-2002, Greg Ungerer (gerg@snapgear.com)
* Copyright (C) 2000, Lineo (www.lineo.com)
* Yaroslav Vinogradov yaroslav.vinogradov@freescale.com
* Copyright Freescale Semiconductor, Inc 2006
* Copyright (c) 2006, emlix, Sebastian Hess <shess@hessware.de>
*/
/***************************************************************************/
#include <linux/clkdev.h>
#include <linux/kernel.h>
#include <linux/param.h>
#include <linux/init.h>
#include <linux/io.h>
#include <asm/machdep.h>
#include <asm/coldfire.h>
#include <asm/mcfsim.h>
#include <asm/mcfuart.h>
#include <asm/mcfdma.h>
#include <asm/mcfwdebug.h>
#include <asm/mcfclk.h>
/***************************************************************************/
DEFINE_CLK(0, "flexbus", 2, MCF_CLK);
DEFINE_CLK(0, "mcfcan.0", 8, MCF_CLK);
DEFINE_CLK(0, "fec.0", 12, MCF_CLK);
DEFINE_CLK(0, "edma", 17, MCF_CLK);
DEFINE_CLK(0, "intc.0", 18, MCF_CLK);
DEFINE_CLK(0, "intc.1", 19, MCF_CLK);
DEFINE_CLK(0, "iack.0", 21, MCF_CLK);
DEFINE_CLK(0, "imx1-i2c.0", 22, MCF_CLK);
DEFINE_CLK(0, "mcfqspi.0", 23, MCF_CLK);
DEFINE_CLK(0, "mcfuart.0", 24, MCF_BUSCLK);
DEFINE_CLK(0, "mcfuart.1", 25, MCF_BUSCLK);
DEFINE_CLK(0, "mcfuart.2", 26, MCF_BUSCLK);
DEFINE_CLK(0, "mcftmr.0", 28, MCF_CLK);
DEFINE_CLK(0, "mcftmr.1", 29, MCF_CLK);
DEFINE_CLK(0, "mcftmr.2", 30, MCF_CLK);
DEFINE_CLK(0, "mcftmr.3", 31, MCF_CLK);
DEFINE_CLK(0, "mcfpit.0", 32, MCF_CLK);
DEFINE_CLK(0, "mcfpit.1", 33, MCF_CLK);
DEFINE_CLK(0, "mcfpit.2", 34, MCF_CLK);
DEFINE_CLK(0, "mcfpit.3", 35, MCF_CLK);
DEFINE_CLK(0, "mcfpwm.0", 36, MCF_CLK);
DEFINE_CLK(0, "mcfeport.0", 37, MCF_CLK);
DEFINE_CLK(0, "mcfwdt.0", 38, MCF_CLK);
DEFINE_CLK(0, "sys.0", 40, MCF_BUSCLK);
DEFINE_CLK(0, "gpio.0", 41, MCF_BUSCLK);
DEFINE_CLK(0, "mcfrtc.0", 42, MCF_CLK);
DEFINE_CLK(0, "mcflcd.0", 43, MCF_CLK);
DEFINE_CLK(0, "mcfusb-otg.0", 44, MCF_CLK);
DEFINE_CLK(0, "mcfusb-host.0", 45, MCF_CLK);
DEFINE_CLK(0, "sdram.0", 46, MCF_CLK);
DEFINE_CLK(0, "ssi.0", 47, MCF_CLK);
DEFINE_CLK(0, "pll.0", 48, MCF_CLK);
DEFINE_CLK(1, "mdha.0", 32, MCF_CLK);
DEFINE_CLK(1, "skha.0", 33, MCF_CLK);
DEFINE_CLK(1, "rng.0", 34, MCF_CLK);
static struct clk_lookup m53xx_clk_lookup[] = {
CLKDEV_INIT("flexbus", NULL, &__clk_0_2),
CLKDEV_INIT("mcfcan.0", NULL, &__clk_0_8),
CLKDEV_INIT("fec.0", NULL, &__clk_0_12),
CLKDEV_INIT("edma", NULL, &__clk_0_17),
CLKDEV_INIT("intc.0", NULL, &__clk_0_18),
CLKDEV_INIT("intc.1", NULL, &__clk_0_19),
CLKDEV_INIT("iack.0", NULL, &__clk_0_21),
CLKDEV_INIT("imx1-i2c.0", NULL, &__clk_0_22),
CLKDEV_INIT("mcfqspi.0", NULL, &__clk_0_23),
CLKDEV_INIT("mcfuart.0", NULL, &__clk_0_24),
CLKDEV_INIT("mcfuart.1", NULL, &__clk_0_25),
CLKDEV_INIT("mcfuart.2", NULL, &__clk_0_26),
CLKDEV_INIT("mcftmr.0", NULL, &__clk_0_28),
CLKDEV_INIT("mcftmr.1", NULL, &__clk_0_29),
CLKDEV_INIT("mcftmr.2", NULL, &__clk_0_30),
CLKDEV_INIT("mcftmr.3", NULL, &__clk_0_31),
CLKDEV_INIT("mcfpit.0", NULL, &__clk_0_32),
CLKDEV_INIT("mcfpit.1", NULL, &__clk_0_33),
CLKDEV_INIT("mcfpit.2", NULL, &__clk_0_34),
CLKDEV_INIT("mcfpit.3", NULL, &__clk_0_35),
CLKDEV_INIT("mcfpwm.0", NULL, &__clk_0_36),
CLKDEV_INIT("mcfeport.0", NULL, &__clk_0_37),
CLKDEV_INIT("mcfwdt.0", NULL, &__clk_0_38),
CLKDEV_INIT(NULL, "sys.0", &__clk_0_40),
CLKDEV_INIT("gpio.0", NULL, &__clk_0_41),
CLKDEV_INIT("mcfrtc.0", NULL, &__clk_0_42),
CLKDEV_INIT("mcflcd.0", NULL, &__clk_0_43),
CLKDEV_INIT("mcfusb-otg.0", NULL, &__clk_0_44),
CLKDEV_INIT("mcfusb-host.0", NULL, &__clk_0_45),
CLKDEV_INIT("sdram.0", NULL, &__clk_0_46),
CLKDEV_INIT("ssi.0", NULL, &__clk_0_47),
CLKDEV_INIT(NULL, "pll.0", &__clk_0_48),
CLKDEV_INIT("mdha.0", NULL, &__clk_1_32),
CLKDEV_INIT("skha.0", NULL, &__clk_1_33),
CLKDEV_INIT("rng.0", NULL, &__clk_1_34),
};
static struct clk * const enable_clks[] __initconst = {
&__clk_0_2, /* flexbus */
&__clk_0_18, /* intc.0 */
&__clk_0_19, /* intc.1 */
&__clk_0_21, /* iack.0 */
&__clk_0_24, /* mcfuart.0 */
&__clk_0_25, /* mcfuart.1 */
&__clk_0_26, /* mcfuart.2 */
&__clk_0_28, /* mcftmr.0 */
&__clk_0_29, /* mcftmr.1 */
&__clk_0_32, /* mcfpit.0 */
&__clk_0_33, /* mcfpit.1 */
&__clk_0_37, /* mcfeport.0 */
&__clk_0_40, /* sys.0 */
&__clk_0_41, /* gpio.0 */
&__clk_0_46, /* sdram.0 */
&__clk_0_48, /* pll.0 */
};
static struct clk * const disable_clks[] __initconst = {
&__clk_0_8, /* mcfcan.0 */
&__clk_0_12, /* fec.0 */
&__clk_0_17, /* edma */
&__clk_0_22, /* imx1-i2c.0 */
&__clk_0_23, /* mcfqspi.0 */
&__clk_0_30, /* mcftmr.2 */
&__clk_0_31, /* mcftmr.3 */
&__clk_0_34, /* mcfpit.2 */
&__clk_0_35, /* mcfpit.3 */
&__clk_0_36, /* mcfpwm.0 */
&__clk_0_38, /* mcfwdt.0 */
&__clk_0_42, /* mcfrtc.0 */
&__clk_0_43, /* mcflcd.0 */
&__clk_0_44, /* mcfusb-otg.0 */
&__clk_0_45, /* mcfusb-host.0 */
&__clk_0_47, /* ssi.0 */
&__clk_1_32, /* mdha.0 */
&__clk_1_33, /* skha.0 */
&__clk_1_34, /* rng.0 */
};
static void __init m53xx_clk_init(void)
{
unsigned i;
/* make sure these clocks are enabled */
for (i = 0; i < ARRAY_SIZE(enable_clks); ++i)
__clk_init_enabled(enable_clks[i]);
/* make sure these clocks are disabled */
for (i = 0; i < ARRAY_SIZE(disable_clks); ++i)
__clk_init_disabled(disable_clks[i]);
clkdev_add_table(m53xx_clk_lookup, ARRAY_SIZE(m53xx_clk_lookup));
}
/***************************************************************************/
static void __init m53xx_qspi_init(void)
{
#if IS_ENABLED(CONFIG_SPI_COLDFIRE_QSPI)
/* setup QSPS pins for QSPI with gpio CS control */
writew(0x01f0, MCFGPIO_PAR_QSPI);
#endif /* IS_ENABLED(CONFIG_SPI_COLDFIRE_QSPI) */
}
/***************************************************************************/
static void __init m53xx_i2c_init(void)
{
#if IS_ENABLED(CONFIG_I2C_IMX)
/* setup Port AS Pin Assignment Register for I2C */
/* set PASPA0 to SCL and PASPA1 to SDA */
u8 r = readb(MCFGPIO_PAR_FECI2C);
r |= 0x0f;
writeb(r, MCFGPIO_PAR_FECI2C);
#endif /* IS_ENABLED(CONFIG_I2C_IMX) */
}
/***************************************************************************/
static void __init m53xx_uarts_init(void)
{
/* UART GPIO initialization */
writew(readw(MCFGPIO_PAR_UART) | 0x0FFF, MCFGPIO_PAR_UART);
}
/***************************************************************************/
static void __init m53xx_fec_init(void)
{
u8 v;
/* Set multi-function pins to ethernet mode for fec0 */
v = readb(MCFGPIO_PAR_FECI2C);
v |= MCF_GPIO_PAR_FECI2C_PAR_MDC_EMDC |
MCF_GPIO_PAR_FECI2C_PAR_MDIO_EMDIO;
writeb(v, MCFGPIO_PAR_FECI2C);
v = readb(MCFGPIO_PAR_FEC);
v = MCF_GPIO_PAR_FEC_PAR_FEC_7W_FEC | MCF_GPIO_PAR_FEC_PAR_FEC_MII_FEC;
writeb(v, MCFGPIO_PAR_FEC);
}
/***************************************************************************/
void __init config_BSP(char *commandp, int size)
{
#if !defined(CONFIG_BOOTPARAM)
/* Copy command line from FLASH to local buffer... */
memcpy(commandp, (char *) 0x4000, 4);
if(strncmp(commandp, "kcl ", 4) == 0){
memcpy(commandp, (char *) 0x4004, size);
commandp[size-1] = 0;
} else {
memset(commandp, 0, size);
}
#endif
mach_sched_init = hw_timer_init;
m53xx_clk_init();
m53xx_uarts_init();
m53xx_fec_init();
m53xx_qspi_init();
m53xx_i2c_init();
#ifdef CONFIG_BDM_DISABLE
/*
* Disable the BDM clocking. This also turns off most of the rest of
* the BDM device. This is good for EMC reasons. This option is not
* incompatible with the memory protection option.
*/
wdebug(MCFDEBUG_CSR, MCFDEBUG_CSR_PSTCLK);
#endif
}
/***************************************************************************/
/* Board initialization */
/***************************************************************************/
/*
* PLL min/max specifications
*/
#define MAX_FVCO 500000 /* KHz */
#define MAX_FSYS 80000 /* KHz */
#define MIN_FSYS 58333 /* KHz */
#define FREF 16000 /* KHz */
#define MAX_MFD 135 /* Multiplier */
#define MIN_MFD 88 /* Multiplier */
#define BUSDIV 6 /* Divider */
/*
* Low Power Divider specifications
*/
#define MIN_LPD (1 << 0) /* Divider (not encoded) */
#define MAX_LPD (1 << 15) /* Divider (not encoded) */
#define DEFAULT_LPD (1 << 1) /* Divider (not encoded) */
#define SYS_CLK_KHZ 80000
#define SYSTEM_PERIOD 12.5
/*
* SDRAM Timing Parameters
*/
#define SDRAM_BL 8 /* # of beats in a burst */
#define SDRAM_TWR 2 /* in clocks */
#define SDRAM_CASL 2.5 /* CASL in clocks */
#define SDRAM_TRCD 2 /* in clocks */
#define SDRAM_TRP 2 /* in clocks */
#define SDRAM_TRFC 7 /* in clocks */
#define SDRAM_TREFI 7800 /* in ns */
#define EXT_SRAM_ADDRESS (0xC0000000)
#define FLASH_ADDRESS (0x00000000)
#define SDRAM_ADDRESS (0x40000000)
#define NAND_FLASH_ADDRESS (0xD0000000)
void wtm_init(void);
void scm_init(void);
void gpio_init(void);
void fbcs_init(void);
void sdramc_init(void);
int clock_pll (int fsys, int flags);
int clock_limp (int);
int clock_exit_limp (void);
int get_sys_clock (void);
asmlinkage void __init sysinit(void)
{
clock_pll(0, 0);
wtm_init();
scm_init();
gpio_init();
fbcs_init();
sdramc_init();
}
void wtm_init(void)
{
/* Disable watchdog timer */
writew(0, MCF_WTM_WCR);
}
#define MCF_SCM_BCR_GBW (0x00000100)
#define MCF_SCM_BCR_GBR (0x00000200)
void scm_init(void)
{
/* All masters are trusted */
writel(0x77777777, MCF_SCM_MPR);
/* Allow supervisor/user, read/write, and trusted/untrusted
access to all slaves */
writel(0, MCF_SCM_PACRA);
writel(0, MCF_SCM_PACRB);
writel(0, MCF_SCM_PACRC);
writel(0, MCF_SCM_PACRD);
writel(0, MCF_SCM_PACRE);
writel(0, MCF_SCM_PACRF);
/* Enable bursts */
writel(MCF_SCM_BCR_GBR | MCF_SCM_BCR_GBW, MCF_SCM_BCR);
}
void fbcs_init(void)
{
writeb(0x3E, MCFGPIO_PAR_CS);
/* Latch chip select */
writel(0x10080000, MCF_FBCS1_CSAR);
writel(0x002A3780, MCF_FBCS1_CSCR);
writel(MCF_FBCS_CSMR_BAM_2M | MCF_FBCS_CSMR_V, MCF_FBCS1_CSMR);
/* Initialize latch to drive signals to inactive states */
writew(0xffff, 0x10080000);
/* External SRAM */
writel(EXT_SRAM_ADDRESS, MCF_FBCS1_CSAR);
writel(MCF_FBCS_CSCR_PS_16 |
MCF_FBCS_CSCR_AA |
MCF_FBCS_CSCR_SBM |
MCF_FBCS_CSCR_WS(1),
MCF_FBCS1_CSCR);
writel(MCF_FBCS_CSMR_BAM_512K | MCF_FBCS_CSMR_V, MCF_FBCS1_CSMR);
/* Boot Flash connected to FBCS0 */
writel(FLASH_ADDRESS, MCF_FBCS0_CSAR);
writel(MCF_FBCS_CSCR_PS_16 |
MCF_FBCS_CSCR_BEM |
MCF_FBCS_CSCR_AA |
MCF_FBCS_CSCR_SBM |
MCF_FBCS_CSCR_WS(7),
MCF_FBCS0_CSCR);
writel(MCF_FBCS_CSMR_BAM_32M | MCF_FBCS_CSMR_V, MCF_FBCS0_CSMR);
}
void sdramc_init(void)
{
/*
* Check to see if the SDRAM has already been initialized
* by a run control tool
*/
if (!(readl(MCF_SDRAMC_SDCR) & MCF_SDRAMC_SDCR_REF)) {
/* SDRAM chip select initialization */
/* Initialize SDRAM chip select */
writel(MCF_SDRAMC_SDCS_BA(SDRAM_ADDRESS) |
MCF_SDRAMC_SDCS_CSSZ(MCF_SDRAMC_SDCS_CSSZ_32MBYTE),
MCF_SDRAMC_SDCS0);
/*
* Basic configuration and initialization
*/
writel(MCF_SDRAMC_SDCFG1_SRD2RW((int)((SDRAM_CASL + 2) + 0.5)) |
MCF_SDRAMC_SDCFG1_SWT2RD(SDRAM_TWR + 1) |
MCF_SDRAMC_SDCFG1_RDLAT((int)((SDRAM_CASL * 2) + 2)) |
MCF_SDRAMC_SDCFG1_ACT2RW((int)(SDRAM_TRCD + 0.5)) |
MCF_SDRAMC_SDCFG1_PRE2ACT((int)(SDRAM_TRP + 0.5)) |
MCF_SDRAMC_SDCFG1_REF2ACT((int)(SDRAM_TRFC + 0.5)) |
MCF_SDRAMC_SDCFG1_WTLAT(3),
MCF_SDRAMC_SDCFG1);
writel(MCF_SDRAMC_SDCFG2_BRD2PRE(SDRAM_BL / 2 + 1) |
MCF_SDRAMC_SDCFG2_BWT2RW(SDRAM_BL / 2 + SDRAM_TWR) |
MCF_SDRAMC_SDCFG2_BRD2WT((int)((SDRAM_CASL + SDRAM_BL / 2 - 1.0) + 0.5)) |
MCF_SDRAMC_SDCFG2_BL(SDRAM_BL - 1),
MCF_SDRAMC_SDCFG2);
/*
* Precharge and enable write to SDMR
*/
writel(MCF_SDRAMC_SDCR_MODE_EN |
MCF_SDRAMC_SDCR_CKE |
MCF_SDRAMC_SDCR_DDR |
MCF_SDRAMC_SDCR_MUX(1) |
MCF_SDRAMC_SDCR_RCNT((int)(((SDRAM_TREFI / (SYSTEM_PERIOD * 64)) - 1) + 0.5)) |
MCF_SDRAMC_SDCR_PS_16 |
MCF_SDRAMC_SDCR_IPALL,
MCF_SDRAMC_SDCR);
/*
* Write extended mode register
*/
writel(MCF_SDRAMC_SDMR_BNKAD_LEMR |
MCF_SDRAMC_SDMR_AD(0x0) |
MCF_SDRAMC_SDMR_CMD,
MCF_SDRAMC_SDMR);
/*
* Write mode register and reset DLL
*/
writel(MCF_SDRAMC_SDMR_BNKAD_LMR |
MCF_SDRAMC_SDMR_AD(0x163) |
MCF_SDRAMC_SDMR_CMD,
MCF_SDRAMC_SDMR);
/*
* Execute a PALL command
*/
writel(readl(MCF_SDRAMC_SDCR) | MCF_SDRAMC_SDCR_IPALL, MCF_SDRAMC_SDCR);
/*
* Perform two REF cycles
*/
writel(readl(MCF_SDRAMC_SDCR) | MCF_SDRAMC_SDCR_IREF, MCF_SDRAMC_SDCR);
writel(readl(MCF_SDRAMC_SDCR) | MCF_SDRAMC_SDCR_IREF, MCF_SDRAMC_SDCR);
/*
* Write mode register and clear reset DLL
*/
writel(MCF_SDRAMC_SDMR_BNKAD_LMR |
MCF_SDRAMC_SDMR_AD(0x063) |
MCF_SDRAMC_SDMR_CMD,
MCF_SDRAMC_SDMR);
/*
* Enable auto refresh and lock SDMR
*/
writel(readl(MCF_SDRAMC_SDCR) & ~MCF_SDRAMC_SDCR_MODE_EN,
MCF_SDRAMC_SDCR);
writel(MCF_SDRAMC_SDCR_REF | MCF_SDRAMC_SDCR_DQS_OE(0xC),
MCF_SDRAMC_SDCR);
}
}
void gpio_init(void)
{
/* Enable UART0 pins */
writew(MCF_GPIO_PAR_UART_PAR_URXD0 | MCF_GPIO_PAR_UART_PAR_UTXD0,
MCFGPIO_PAR_UART);
/*
* Initialize TIN3 as a GPIO output to enable the write
* half of the latch.
*/
writeb(0x00, MCFGPIO_PAR_TIMER);
writeb(0x08, MCFGPIO_PDDR_TIMER);
writeb(0x00, MCFGPIO_PCLRR_TIMER);
}
int clock_pll(int fsys, int flags)
{
int fref, temp, fout, mfd;
u32 i;
fref = FREF;
if (fsys == 0) {
/* Return current PLL output */
mfd = readb(MCF_PLL_PFDR);
return (fref * mfd / (BUSDIV * 4));
}
/* Check bounds of requested system clock */
if (fsys > MAX_FSYS)
fsys = MAX_FSYS;
if (fsys < MIN_FSYS)
fsys = MIN_FSYS;
/* Multiplying by 100 when calculating the temp value,
and then dividing by 100 to calculate the mfd allows
for exact values without needing to include floating
point libraries. */
temp = 100 * fsys / fref;
mfd = 4 * BUSDIV * temp / 100;
/* Determine the output frequency for selected values */
fout = (fref * mfd / (BUSDIV * 4));
/*
* Check to see if the SDRAM has already been initialized.
* If it has then the SDRAM needs to be put into self refresh
* mode before reprogramming the PLL.
*/
if (readl(MCF_SDRAMC_SDCR) & MCF_SDRAMC_SDCR_REF)
/* Put SDRAM into self refresh mode */
writel(readl(MCF_SDRAMC_SDCR) & ~MCF_SDRAMC_SDCR_CKE,
MCF_SDRAMC_SDCR);
/*
* Initialize the PLL to generate the new system clock frequency.
* The device must be put into LIMP mode to reprogram the PLL.
*/
/* Enter LIMP mode */
clock_limp(DEFAULT_LPD);
/* Reprogram PLL for desired fsys */
writeb(MCF_PLL_PODR_CPUDIV(BUSDIV/3) | MCF_PLL_PODR_BUSDIV(BUSDIV),
MCF_PLL_PODR);
writeb(mfd, MCF_PLL_PFDR);
/* Exit LIMP mode */
clock_exit_limp();
/*
* Return the SDRAM to normal operation if it is in use.
*/
if (readl(MCF_SDRAMC_SDCR) & MCF_SDRAMC_SDCR_REF)
/* Exit self refresh mode */
writel(readl(MCF_SDRAMC_SDCR) | MCF_SDRAMC_SDCR_CKE,
MCF_SDRAMC_SDCR);
/* Errata - workaround for SDRAM operation after exiting LIMP mode */
writel(MCF_SDRAMC_REFRESH, MCF_SDRAMC_LIMP_FIX);
/* wait for DQS logic to relock */
for (i = 0; i < 0x200; i++)
;
return fout;
}
int clock_limp(int div)
{
u32 temp;
/* Check bounds of divider */
if (div < MIN_LPD)
div = MIN_LPD;
if (div > MAX_LPD)
div = MAX_LPD;
/* Save of the current value of the SSIDIV so we don't
overwrite the value*/
temp = readw(MCF_CCM_CDR) & MCF_CCM_CDR_SSIDIV(0xF);
/* Apply the divider to the system clock */
writew(MCF_CCM_CDR_LPDIV(div) | MCF_CCM_CDR_SSIDIV(temp), MCF_CCM_CDR);
writew(readw(MCF_CCM_MISCCR) | MCF_CCM_MISCCR_LIMP, MCF_CCM_MISCCR);
return (FREF/(3*(1 << div)));
}
int clock_exit_limp(void)
{
int fout;
/* Exit LIMP mode */
writew(readw(MCF_CCM_MISCCR) & ~MCF_CCM_MISCCR_LIMP, MCF_CCM_MISCCR);
/* Wait for PLL to lock */
while (!(readw(MCF_CCM_MISCCR) & MCF_CCM_MISCCR_PLL_LOCK))
;
fout = get_sys_clock();
return fout;
}
int get_sys_clock(void)
{
int divider;
/* Test to see if device is in LIMP mode */
if (readw(MCF_CCM_MISCCR) & MCF_CCM_MISCCR_LIMP) {
divider = readw(MCF_CCM_CDR) & MCF_CCM_CDR_LPDIV(0xF);
return (FREF/(2 << divider));
}
else
return (FREF * readb(MCF_PLL_PFDR)) / (BUSDIV * 4);
}
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