summaryrefslogtreecommitdiffstats
path: root/arch/arm/mach-prima2/rtciobrg.c
diff options
context:
space:
mode:
authorDaniel Baumann <daniel.baumann@progress-linux.org>2024-05-06 01:02:30 +0000
committerDaniel Baumann <daniel.baumann@progress-linux.org>2024-05-06 01:02:30 +0000
commit76cb841cb886eef6b3bee341a2266c76578724ad (patch)
treef5892e5ba6cc11949952a6ce4ecbe6d516d6ce58 /arch/arm/mach-prima2/rtciobrg.c
parentInitial commit. (diff)
downloadlinux-76cb841cb886eef6b3bee341a2266c76578724ad.tar.xz
linux-76cb841cb886eef6b3bee341a2266c76578724ad.zip
Adding upstream version 4.19.249.upstream/4.19.249
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'arch/arm/mach-prima2/rtciobrg.c')
-rw-r--r--arch/arm/mach-prima2/rtciobrg.c180
1 files changed, 180 insertions, 0 deletions
diff --git a/arch/arm/mach-prima2/rtciobrg.c b/arch/arm/mach-prima2/rtciobrg.c
new file mode 100644
index 000000000..d4852d24d
--- /dev/null
+++ b/arch/arm/mach-prima2/rtciobrg.c
@@ -0,0 +1,180 @@
+/*
+ * RTC I/O Bridge interfaces for CSR SiRFprimaII/atlas7
+ * ARM access the registers of SYSRTC, GPSRTC and PWRC through this module
+ *
+ * Copyright (c) 2011 Cambridge Silicon Radio Limited, a CSR plc group company.
+ *
+ * Licensed under GPLv2 or later.
+ */
+
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/io.h>
+#include <linux/regmap.h>
+#include <linux/of.h>
+#include <linux/of_address.h>
+#include <linux/of_device.h>
+#include <linux/of_platform.h>
+
+#define SIRFSOC_CPUIOBRG_CTRL 0x00
+#define SIRFSOC_CPUIOBRG_WRBE 0x04
+#define SIRFSOC_CPUIOBRG_ADDR 0x08
+#define SIRFSOC_CPUIOBRG_DATA 0x0c
+
+/*
+ * suspend asm codes will access this address to make system deepsleep
+ * after DRAM becomes self-refresh
+ */
+void __iomem *sirfsoc_rtciobrg_base;
+static DEFINE_SPINLOCK(rtciobrg_lock);
+
+/*
+ * symbols without lock are only used by suspend asm codes
+ * and these symbols are not exported too
+ */
+void sirfsoc_rtc_iobrg_wait_sync(void)
+{
+ while (readl_relaxed(sirfsoc_rtciobrg_base + SIRFSOC_CPUIOBRG_CTRL))
+ cpu_relax();
+}
+
+void sirfsoc_rtc_iobrg_besyncing(void)
+{
+ unsigned long flags;
+
+ spin_lock_irqsave(&rtciobrg_lock, flags);
+
+ sirfsoc_rtc_iobrg_wait_sync();
+
+ spin_unlock_irqrestore(&rtciobrg_lock, flags);
+}
+EXPORT_SYMBOL_GPL(sirfsoc_rtc_iobrg_besyncing);
+
+u32 __sirfsoc_rtc_iobrg_readl(u32 addr)
+{
+ sirfsoc_rtc_iobrg_wait_sync();
+
+ writel_relaxed(0x00, sirfsoc_rtciobrg_base + SIRFSOC_CPUIOBRG_WRBE);
+ writel_relaxed(addr, sirfsoc_rtciobrg_base + SIRFSOC_CPUIOBRG_ADDR);
+ writel_relaxed(0x01, sirfsoc_rtciobrg_base + SIRFSOC_CPUIOBRG_CTRL);
+
+ sirfsoc_rtc_iobrg_wait_sync();
+
+ return readl_relaxed(sirfsoc_rtciobrg_base + SIRFSOC_CPUIOBRG_DATA);
+}
+
+u32 sirfsoc_rtc_iobrg_readl(u32 addr)
+{
+ unsigned long flags, val;
+
+ /* TODO: add hwspinlock to sync with M3 */
+ spin_lock_irqsave(&rtciobrg_lock, flags);
+
+ val = __sirfsoc_rtc_iobrg_readl(addr);
+
+ spin_unlock_irqrestore(&rtciobrg_lock, flags);
+
+ return val;
+}
+EXPORT_SYMBOL_GPL(sirfsoc_rtc_iobrg_readl);
+
+void sirfsoc_rtc_iobrg_pre_writel(u32 val, u32 addr)
+{
+ sirfsoc_rtc_iobrg_wait_sync();
+
+ writel_relaxed(0xf1, sirfsoc_rtciobrg_base + SIRFSOC_CPUIOBRG_WRBE);
+ writel_relaxed(addr, sirfsoc_rtciobrg_base + SIRFSOC_CPUIOBRG_ADDR);
+
+ writel_relaxed(val, sirfsoc_rtciobrg_base + SIRFSOC_CPUIOBRG_DATA);
+}
+
+void sirfsoc_rtc_iobrg_writel(u32 val, u32 addr)
+{
+ unsigned long flags;
+
+ /* TODO: add hwspinlock to sync with M3 */
+ spin_lock_irqsave(&rtciobrg_lock, flags);
+
+ sirfsoc_rtc_iobrg_pre_writel(val, addr);
+
+ writel_relaxed(0x01, sirfsoc_rtciobrg_base + SIRFSOC_CPUIOBRG_CTRL);
+
+ sirfsoc_rtc_iobrg_wait_sync();
+
+ spin_unlock_irqrestore(&rtciobrg_lock, flags);
+}
+EXPORT_SYMBOL_GPL(sirfsoc_rtc_iobrg_writel);
+
+
+static int regmap_iobg_regwrite(void *context, unsigned int reg,
+ unsigned int val)
+{
+ sirfsoc_rtc_iobrg_writel(val, reg);
+ return 0;
+}
+
+static int regmap_iobg_regread(void *context, unsigned int reg,
+ unsigned int *val)
+{
+ *val = (u32)sirfsoc_rtc_iobrg_readl(reg);
+ return 0;
+}
+
+static struct regmap_bus regmap_iobg = {
+ .reg_write = regmap_iobg_regwrite,
+ .reg_read = regmap_iobg_regread,
+};
+
+/**
+ * devm_regmap_init_iobg(): Initialise managed register map
+ *
+ * @iobg: Device that will be interacted with
+ * @config: Configuration for register map
+ *
+ * The return value will be an ERR_PTR() on error or a valid pointer
+ * to a struct regmap. The regmap will be automatically freed by the
+ * device management code.
+ */
+struct regmap *devm_regmap_init_iobg(struct device *dev,
+ const struct regmap_config *config)
+{
+ const struct regmap_bus *bus = &regmap_iobg;
+
+ return devm_regmap_init(dev, bus, dev, config);
+}
+EXPORT_SYMBOL_GPL(devm_regmap_init_iobg);
+
+static const struct of_device_id rtciobrg_ids[] = {
+ { .compatible = "sirf,prima2-rtciobg" },
+ {}
+};
+
+static int sirfsoc_rtciobrg_probe(struct platform_device *op)
+{
+ struct device_node *np = op->dev.of_node;
+
+ sirfsoc_rtciobrg_base = of_iomap(np, 0);
+ if (!sirfsoc_rtciobrg_base)
+ panic("unable to map rtc iobrg registers\n");
+
+ return 0;
+}
+
+static struct platform_driver sirfsoc_rtciobrg_driver = {
+ .probe = sirfsoc_rtciobrg_probe,
+ .driver = {
+ .name = "sirfsoc-rtciobrg",
+ .of_match_table = rtciobrg_ids,
+ },
+};
+
+static int __init sirfsoc_rtciobrg_init(void)
+{
+ return platform_driver_register(&sirfsoc_rtciobrg_driver);
+}
+postcore_initcall(sirfsoc_rtciobrg_init);
+
+MODULE_AUTHOR("Zhiwu Song <zhiwu.song@csr.com>");
+MODULE_AUTHOR("Barry Song <baohua.song@csr.com>");
+MODULE_DESCRIPTION("CSR SiRFprimaII rtc io bridge");
+MODULE_LICENSE("GPL v2");