u-boot/arch/arm/mach-kirkwood/include/mach/kw88f6281.h
Pali Rohár f395cf9cac arm: kirkwood: 88f6281: Detect CONFIG_SYS_TCLK from SAR register
Bit 21 in SAR register specifies if TCLK is running at 166 MHz or 200 MHz.
This information is undocumented in public Marvell Kirkwood Functional
Specifications [2], but is available in Linux v3.15 kirkwood code [1].

Commit 8ac303d49f ("arm: kirkwood: Do not overwrite CONFIG_SYS_TCLK")
broke support for Marvell 88F6281 SoCs because it was expected that all
those SoCs have TCLK running at 200 MHz as specified in Marvell 88F6281
Hardware Specifications [3].

Fix broken support for 88F6281 by detecting CONFIG_SYS_TCLK from SAR
register, like it was doing Linux v3.15.

[1] - https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/tree/arch/arm/mach-kirkwood/common.c?h=v3.15#n542
[2] - https://web.archive.org/web/20130730091033/http://www.marvell.com/embedded-processors/kirkwood/assets/FS_88F6180_9x_6281_OpenSource.pdf
[3] - https://web.archive.org/web/20120620073511/http://www.marvell.com/embedded-processors/kirkwood/assets/HW_88F6281_OpenSource.pdf

Update by Stefan 2022-08-23:
- Fix compilation error for ds109

Fixes: 8ac303d49f ("arm: kirkwood: Do not overwrite CONFIG_SYS_TCLK")
Signed-off-by: Pali Rohár <pali@kernel.org>
Reviewed-by: Stefan Roese <sr@denx.de>
2022-08-23 12:38:47 +02:00

21 lines
588 B
C

/* SPDX-License-Identifier: GPL-2.0+ */
/*
* (C) Copyright 2009
* Marvell Semiconductor <www.marvell.com>
* Written-by: Prafulla Wadaskar <prafulla@marvell.com>
*
* Header file for Feroceon CPU core 88FR131 Based KW88F6281 SOC.
*/
#ifndef _ASM_ARCH_KW88F6281_H
#define _ASM_ARCH_KW88F6281_H
/* SOC specific definitions */
#define KW88F6281_REGS_PHYS_BASE 0xf1000000
#define KW_REGS_PHY_BASE KW88F6281_REGS_PHYS_BASE
/* TCLK Core Clock definition */
#define CONFIG_SYS_TCLK ((readl(CONFIG_SAR_REG) & BIT(21)) ? \
166666667 : 200000000)
#endif /* _ASM_ARCH_KW88F6281_H */