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-rw-r--r--arch/powerpc/boot/pq2.c102
1 files changed, 102 insertions, 0 deletions
diff --git a/arch/powerpc/boot/pq2.c b/arch/powerpc/boot/pq2.c
new file mode 100644
index 00000000000..f6d118558f1
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+++ b/arch/powerpc/boot/pq2.c
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+/*
+ * PowerQUICC II 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 "pq2.h"
+#include "stdio.h"
+#include "io.h"
+
+#define PQ2_SCCR (0x10c80/4) /* System Clock Configuration Register */
+#define PQ2_SCMR (0x10c88/4) /* System Clock Mode Register */
+
+static int pq2_corecnf_map[] = {
+ 3, 2, 2, 2, 4, 4, 5, 9, 6, 11, 8, 10, 3, 12, 7, -1,
+ 6, 5, 13, 2, 14, 4, 15, 9, 0, 11, 8, 10, 16, 12, 7, -1
+};
+
+/* Get various clocks from crystal frequency.
+ * Returns zero on failure and non-zero on success.
+ */
+int pq2_get_clocks(u32 crystal, u32 *sysfreq, u32 *corefreq,
+ u32 *timebase, u32 *brgfreq)
+{
+ u32 *immr;
+ u32 sccr, scmr, mainclk, busclk;
+ int corecnf, busdf, plldf, pllmf, dfbrg;
+
+ immr = fsl_get_immr();
+ if (!immr) {
+ printf("pq2_get_clocks: Couldn't get IMMR base.\r\n");
+ return 0;
+ }
+
+ sccr = in_be32(&immr[PQ2_SCCR]);
+ scmr = in_be32(&immr[PQ2_SCMR]);
+
+ dfbrg = sccr & 3;
+ corecnf = (scmr >> 24) & 0x1f;
+ busdf = (scmr >> 20) & 0xf;
+ plldf = (scmr >> 12) & 1;
+ pllmf = scmr & 0xfff;
+
+ mainclk = crystal * (pllmf + 1) / (plldf + 1);
+ busclk = mainclk / (busdf + 1);
+
+ if (sysfreq)
+ *sysfreq = mainclk / 2;
+ if (timebase)
+ *timebase = busclk / 4;
+ if (brgfreq)
+ *brgfreq = mainclk / (1 << ((dfbrg + 1) * 2));
+
+ if (corefreq) {
+ int coremult = pq2_corecnf_map[corecnf];
+
+ if (coremult < 0)
+ *corefreq = mainclk / 2;
+ else if (coremult == 0)
+ return 0;
+ else
+ *corefreq = busclk * coremult / 2;
+ }
+
+ return 1;
+}
+
+/* Set common device tree fields based on the given clock frequencies. */
+void pq2_set_clocks(u32 sysfreq, u32 corefreq, u32 timebase, u32 brgfreq)
+{
+ void *node;
+
+ dt_fixup_cpu_clocks(corefreq, timebase, sysfreq);
+
+ node = finddevice("/soc/cpm");
+ if (node)
+ setprop(node, "clock-frequency", &sysfreq, 4);
+
+ node = finddevice("/soc/cpm/brg");
+ if (node)
+ setprop(node, "clock-frequency", &brgfreq, 4);
+}
+
+int pq2_fixup_clocks(u32 crystal)
+{
+ u32 sysfreq, corefreq, timebase, brgfreq;
+
+ if (!pq2_get_clocks(crystal, &sysfreq, &corefreq, &timebase, &brgfreq))
+ return 0;
+
+ pq2_set_clocks(sysfreq, corefreq, timebase, brgfreq);
+ return 1;
+}