diff options
author | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-04-07 18:49:45 +0000 |
---|---|---|
committer | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-04-07 18:49:45 +0000 |
commit | 2c3c1048746a4622d8c89a29670120dc8fab93c4 (patch) | |
tree | 848558de17fb3008cdf4d861b01ac7781903ce39 /arch/powerpc/boot/mpc8xx.c | |
parent | Initial commit. (diff) | |
download | linux-2c3c1048746a4622d8c89a29670120dc8fab93c4.tar.xz linux-2c3c1048746a4622d8c89a29670120dc8fab93c4.zip |
Adding upstream version 6.1.76.upstream/6.1.76
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'arch/powerpc/boot/mpc8xx.c')
-rw-r--r-- | arch/powerpc/boot/mpc8xx.c | 78 |
1 files changed, 78 insertions, 0 deletions
diff --git a/arch/powerpc/boot/mpc8xx.c b/arch/powerpc/boot/mpc8xx.c new file mode 100644 index 000000000..e19ef64df --- /dev/null +++ b/arch/powerpc/boot/mpc8xx.c @@ -0,0 +1,78 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * MPC8xx support functions + * + * Author: Scott Wood <scottwood@freescale.com> + * + * Copyright (c) 2007 Freescale Semiconductor, Inc. + */ + +#include "ops.h" +#include "types.h" +#include "fsl-soc.h" +#include "mpc8xx.h" +#include "stdio.h" +#include "io.h" + +#define MPC8XX_PLPRCR (0x284/4) /* PLL and Reset Control Register */ + +/* Return system clock from crystal frequency */ +u32 mpc885_get_clock(u32 crystal) +{ + u32 *immr; + u32 plprcr; + int mfi, mfn, mfd, pdf; + u32 ret; + + immr = fsl_get_immr(); + if (!immr) { + printf("mpc885_get_clock: Couldn't get IMMR base.\r\n"); + return 0; + } + + plprcr = in_be32(&immr[MPC8XX_PLPRCR]); + + mfi = (plprcr >> 16) & 15; + if (mfi < 5) { + printf("Warning: PLPRCR[MFI] value of %d out-of-bounds\r\n", + mfi); + mfi = 5; + } + + pdf = (plprcr >> 1) & 0xf; + mfd = (plprcr >> 22) & 0x1f; + mfn = (plprcr >> 27) & 0x1f; + + ret = crystal * mfi; + + if (mfn != 0) + ret += crystal * mfn / (mfd + 1); + + return ret / (pdf + 1); +} + +/* Set common device tree fields based on the given clock frequencies. */ +void mpc8xx_set_clocks(u32 sysclk) +{ + void *node; + + dt_fixup_cpu_clocks(sysclk, sysclk / 16, sysclk); + + node = finddevice("/soc/cpm"); + if (node) + setprop(node, "clock-frequency", &sysclk, 4); + + node = finddevice("/soc/cpm/brg"); + if (node) + setprop(node, "clock-frequency", &sysclk, 4); +} + +int mpc885_fixup_clocks(u32 crystal) +{ + u32 sysclk = mpc885_get_clock(crystal); + if (!sysclk) + return 0; + + mpc8xx_set_clocks(sysclk); + return 1; +} |