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authorLinus Torvalds <torvalds@woody.linux-foundation.org>2007-10-11 21:55:47 -0700
committerLinus Torvalds <torvalds@woody.linux-foundation.org>2007-10-11 21:55:47 -0700
commite86908614f2c7fec401827e5cefd7a6ea9407f85 (patch)
treefcb5d9e52422b37bdaf0e647126ebdfc1680f162 /arch/powerpc/boot/mpc8xx.c
parent547307420931344a868275bd7ea7a30f117a15a9 (diff)
parent9b4b8feb962f4b3e74768b7205f1f8f6cce87238 (diff)
Merge branch 'master' of git://git.kernel.org/pub/scm/linux/kernel/git/paulus/powerpc
* 'master' of git://git.kernel.org/pub/scm/linux/kernel/git/paulus/powerpc: (408 commits) [POWERPC] Add memchr() to the bootwrapper [POWERPC] Implement logging of unhandled signals [POWERPC] Add legacy serial support for OPB with flattened device tree [POWERPC] Use 1TB segments [POWERPC] XilinxFB: Allow fixed framebuffer base address [POWERPC] XilinxFB: Add support for custom screen resolution [POWERPC] XilinxFB: Use pdata to pass around framebuffer parameters [POWERPC] PCI: Add 64-bit physical address support to setup_indirect_pci [POWERPC] 4xx: Kilauea defconfig file [POWERPC] 4xx: Kilauea DTS [POWERPC] 4xx: Add AMCC Kilauea eval board support to platforms/40x [POWERPC] 4xx: Add AMCC 405EX support to cputable.c [POWERPC] Adjust TASK_SIZE on ppc32 systems to 3GB that are capable [POWERPC] Use PAGE_OFFSET to tell if an address is user/kernel in SW TLB handlers [POWERPC] 85xx: Enable FP emulation in MPC8560 ADS defconfig [POWERPC] 85xx: Killed <asm/mpc85xx.h> [POWERPC] 85xx: Add cpm nodes for 8541/8555 CDS [POWERPC] 85xx: Convert mpc8560ads to the new CPM binding. [POWERPC] mpc8272ads: Remove muram from the CPM reg property. [POWERPC] Make clockevents work on PPC601 processors ... Fixed up conflict in Documentation/powerpc/booting-without-of.txt manually.
Diffstat (limited to 'arch/powerpc/boot/mpc8xx.c')
-rw-r--r--arch/powerpc/boot/mpc8xx.c82
1 files changed, 82 insertions, 0 deletions
diff --git a/arch/powerpc/boot/mpc8xx.c b/arch/powerpc/boot/mpc8xx.c
new file mode 100644
index 00000000000..add55a7f184
--- /dev/null
+++ b/arch/powerpc/boot/mpc8xx.c
@@ -0,0 +1,82 @@
+/*
+ * MPC8xx support functions
+ *
+ * Author: Scott Wood <scottwood@freescale.com>
+ *
+ * Copyright (c) 2007 Freescale Semiconductor, Inc.
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License version 2 as published
+ * by the Free Software Foundation.
+ */
+
+#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, div;
+ 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;
+ div = (plprcr >> 20) & 3;
+ 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;
+}