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Diffstat (limited to 'drivers/clk/at91/pmc.c')
-rw-r--r--drivers/clk/at91/pmc.c215
1 files changed, 215 insertions, 0 deletions
diff --git a/drivers/clk/at91/pmc.c b/drivers/clk/at91/pmc.c
new file mode 100644
index 000000000..1fa27f4ea
--- /dev/null
+++ b/drivers/clk/at91/pmc.c
@@ -0,0 +1,215 @@
+/*
+ * Copyright (C) 2013 Boris BREZILLON <b.brezillon@overkiz.com>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ */
+
+#include <linux/clk-provider.h>
+#include <linux/clkdev.h>
+#include <linux/clk/at91_pmc.h>
+#include <linux/of.h>
+#include <linux/mfd/syscon.h>
+#include <linux/platform_device.h>
+#include <linux/regmap.h>
+#include <linux/syscore_ops.h>
+
+#include <asm/proc-fns.h>
+
+#include "pmc.h"
+
+#define PMC_MAX_IDS 128
+#define PMC_MAX_PCKS 8
+
+int of_at91_get_clk_range(struct device_node *np, const char *propname,
+ struct clk_range *range)
+{
+ u32 min, max;
+ int ret;
+
+ ret = of_property_read_u32_index(np, propname, 0, &min);
+ if (ret)
+ return ret;
+
+ ret = of_property_read_u32_index(np, propname, 1, &max);
+ if (ret)
+ return ret;
+
+ if (range) {
+ range->min = min;
+ range->max = max;
+ }
+
+ return 0;
+}
+EXPORT_SYMBOL_GPL(of_at91_get_clk_range);
+
+#ifdef CONFIG_PM
+static struct regmap *pmcreg;
+
+static u8 registered_ids[PMC_MAX_IDS];
+static u8 registered_pcks[PMC_MAX_PCKS];
+
+static struct
+{
+ u32 scsr;
+ u32 pcsr0;
+ u32 uckr;
+ u32 mor;
+ u32 mcfr;
+ u32 pllar;
+ u32 mckr;
+ u32 usb;
+ u32 imr;
+ u32 pcsr1;
+ u32 pcr[PMC_MAX_IDS];
+ u32 audio_pll0;
+ u32 audio_pll1;
+ u32 pckr[PMC_MAX_PCKS];
+} pmc_cache;
+
+/*
+ * As Peripheral ID 0 is invalid on AT91 chips, the identifier is stored
+ * without alteration in the table, and 0 is for unused clocks.
+ */
+void pmc_register_id(u8 id)
+{
+ int i;
+
+ for (i = 0; i < PMC_MAX_IDS; i++) {
+ if (registered_ids[i] == 0) {
+ registered_ids[i] = id;
+ break;
+ }
+ if (registered_ids[i] == id)
+ break;
+ }
+}
+
+/*
+ * As Programmable Clock 0 is valid on AT91 chips, there is an offset
+ * of 1 between the stored value and the real clock ID.
+ */
+void pmc_register_pck(u8 pck)
+{
+ int i;
+
+ for (i = 0; i < PMC_MAX_PCKS; i++) {
+ if (registered_pcks[i] == 0) {
+ registered_pcks[i] = pck + 1;
+ break;
+ }
+ if (registered_pcks[i] == (pck + 1))
+ break;
+ }
+}
+
+static int pmc_suspend(void)
+{
+ int i;
+ u8 num;
+
+ regmap_read(pmcreg, AT91_PMC_SCSR, &pmc_cache.scsr);
+ regmap_read(pmcreg, AT91_PMC_PCSR, &pmc_cache.pcsr0);
+ regmap_read(pmcreg, AT91_CKGR_UCKR, &pmc_cache.uckr);
+ regmap_read(pmcreg, AT91_CKGR_MOR, &pmc_cache.mor);
+ regmap_read(pmcreg, AT91_CKGR_MCFR, &pmc_cache.mcfr);
+ regmap_read(pmcreg, AT91_CKGR_PLLAR, &pmc_cache.pllar);
+ regmap_read(pmcreg, AT91_PMC_MCKR, &pmc_cache.mckr);
+ regmap_read(pmcreg, AT91_PMC_USB, &pmc_cache.usb);
+ regmap_read(pmcreg, AT91_PMC_IMR, &pmc_cache.imr);
+ regmap_read(pmcreg, AT91_PMC_PCSR1, &pmc_cache.pcsr1);
+
+ for (i = 0; registered_ids[i]; i++) {
+ regmap_write(pmcreg, AT91_PMC_PCR,
+ (registered_ids[i] & AT91_PMC_PCR_PID_MASK));
+ regmap_read(pmcreg, AT91_PMC_PCR,
+ &pmc_cache.pcr[registered_ids[i]]);
+ }
+ for (i = 0; registered_pcks[i]; i++) {
+ num = registered_pcks[i] - 1;
+ regmap_read(pmcreg, AT91_PMC_PCKR(num), &pmc_cache.pckr[num]);
+ }
+
+ return 0;
+}
+
+static bool pmc_ready(unsigned int mask)
+{
+ unsigned int status;
+
+ regmap_read(pmcreg, AT91_PMC_SR, &status);
+
+ return ((status & mask) == mask) ? 1 : 0;
+}
+
+static void pmc_resume(void)
+{
+ int i;
+ u8 num;
+ u32 tmp;
+ u32 mask = AT91_PMC_MCKRDY | AT91_PMC_LOCKA;
+
+ regmap_read(pmcreg, AT91_PMC_MCKR, &tmp);
+ if (pmc_cache.mckr != tmp)
+ pr_warn("MCKR was not configured properly by the firmware\n");
+ regmap_read(pmcreg, AT91_CKGR_PLLAR, &tmp);
+ if (pmc_cache.pllar != tmp)
+ pr_warn("PLLAR was not configured properly by the firmware\n");
+
+ regmap_write(pmcreg, AT91_PMC_SCER, pmc_cache.scsr);
+ regmap_write(pmcreg, AT91_PMC_PCER, pmc_cache.pcsr0);
+ regmap_write(pmcreg, AT91_CKGR_UCKR, pmc_cache.uckr);
+ regmap_write(pmcreg, AT91_CKGR_MOR, pmc_cache.mor);
+ regmap_write(pmcreg, AT91_CKGR_MCFR, pmc_cache.mcfr);
+ regmap_write(pmcreg, AT91_PMC_USB, pmc_cache.usb);
+ regmap_write(pmcreg, AT91_PMC_IMR, pmc_cache.imr);
+ regmap_write(pmcreg, AT91_PMC_PCER1, pmc_cache.pcsr1);
+
+ for (i = 0; registered_ids[i]; i++) {
+ regmap_write(pmcreg, AT91_PMC_PCR,
+ pmc_cache.pcr[registered_ids[i]] |
+ AT91_PMC_PCR_CMD);
+ }
+ for (i = 0; registered_pcks[i]; i++) {
+ num = registered_pcks[i] - 1;
+ regmap_write(pmcreg, AT91_PMC_PCKR(num), pmc_cache.pckr[num]);
+ }
+
+ if (pmc_cache.uckr & AT91_PMC_UPLLEN)
+ mask |= AT91_PMC_LOCKU;
+
+ while (!pmc_ready(mask))
+ cpu_relax();
+}
+
+static struct syscore_ops pmc_syscore_ops = {
+ .suspend = pmc_suspend,
+ .resume = pmc_resume,
+};
+
+static const struct of_device_id sama5d2_pmc_dt_ids[] = {
+ { .compatible = "atmel,sama5d2-pmc" },
+ { /* sentinel */ }
+};
+
+static int __init pmc_register_ops(void)
+{
+ struct device_node *np;
+
+ np = of_find_matching_node(NULL, sama5d2_pmc_dt_ids);
+
+ pmcreg = syscon_node_to_regmap(np);
+ if (IS_ERR(pmcreg))
+ return PTR_ERR(pmcreg);
+
+ register_syscore_ops(&pmc_syscore_ops);
+
+ return 0;
+}
+/* This has to happen before arch_initcall because of the tcb_clksrc driver */
+postcore_initcall(pmc_register_ops);
+#endif