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authorJosé Pekkarinen <jose.pekkarinen@nokia.com>2016-04-11 10:41:07 +0300
committerJosé Pekkarinen <jose.pekkarinen@nokia.com>2016-04-13 08:17:18 +0300
commite09b41010ba33a20a87472ee821fa407a5b8da36 (patch)
treed10dc367189862e7ca5c592f033dc3726e1df4e3 /kernel/drivers/clk/imx/clk.c
parentf93b97fd65072de626c074dbe099a1fff05ce060 (diff)
These changes are the raw update to linux-4.4.6-rt14. Kernel sources
are taken from kernel.org, and rt patch from the rt wiki download page. During the rebasing, the following patch collided: Force tick interrupt and get rid of softirq magic(I70131fb85). Collisions have been removed because its logic was found on the source already. Change-Id: I7f57a4081d9deaa0d9ccfc41a6c8daccdee3b769 Signed-off-by: José Pekkarinen <jose.pekkarinen@nokia.com>
Diffstat (limited to 'kernel/drivers/clk/imx/clk.c')
-rw-r--r--kernel/drivers/clk/imx/clk.c113
1 files changed, 113 insertions, 0 deletions
diff --git a/kernel/drivers/clk/imx/clk.c b/kernel/drivers/clk/imx/clk.c
new file mode 100644
index 000000000..a634b1185
--- /dev/null
+++ b/kernel/drivers/clk/imx/clk.c
@@ -0,0 +1,113 @@
+#include <linux/clk.h>
+#include <linux/err.h>
+#include <linux/of.h>
+#include <linux/slab.h>
+#include <linux/spinlock.h>
+#include "clk.h"
+
+DEFINE_SPINLOCK(imx_ccm_lock);
+
+void __init imx_check_clocks(struct clk *clks[], unsigned int count)
+{
+ unsigned i;
+
+ for (i = 0; i < count; i++)
+ if (IS_ERR(clks[i]))
+ pr_err("i.MX clk %u: register failed with %ld\n",
+ i, PTR_ERR(clks[i]));
+}
+
+static struct clk * __init imx_obtain_fixed_clock_from_dt(const char *name)
+{
+ struct of_phandle_args phandle;
+ struct clk *clk = ERR_PTR(-ENODEV);
+ char *path;
+
+ path = kasprintf(GFP_KERNEL, "/clocks/%s", name);
+ if (!path)
+ return ERR_PTR(-ENOMEM);
+
+ phandle.np = of_find_node_by_path(path);
+ kfree(path);
+
+ if (phandle.np) {
+ clk = of_clk_get_from_provider(&phandle);
+ of_node_put(phandle.np);
+ }
+ return clk;
+}
+
+struct clk * __init imx_obtain_fixed_clock(
+ const char *name, unsigned long rate)
+{
+ struct clk *clk;
+
+ clk = imx_obtain_fixed_clock_from_dt(name);
+ if (IS_ERR(clk))
+ clk = imx_clk_fixed(name, rate);
+ return clk;
+}
+
+/*
+ * This fixups the register CCM_CSCMR1 write value.
+ * The write/read/divider values of the aclk_podf field
+ * of that register have the relationship described by
+ * the following table:
+ *
+ * write value read value divider
+ * 3b'000 3b'110 7
+ * 3b'001 3b'111 8
+ * 3b'010 3b'100 5
+ * 3b'011 3b'101 6
+ * 3b'100 3b'010 3
+ * 3b'101 3b'011 4
+ * 3b'110 3b'000 1
+ * 3b'111 3b'001 2(default)
+ *
+ * That's why we do the xor operation below.
+ */
+#define CSCMR1_FIXUP 0x00600000
+
+void imx_cscmr1_fixup(u32 *val)
+{
+ *val ^= CSCMR1_FIXUP;
+ return;
+}
+
+static int imx_keep_uart_clocks __initdata;
+static struct clk ** const *imx_uart_clocks __initdata;
+
+static int __init imx_keep_uart_clocks_param(char *str)
+{
+ imx_keep_uart_clocks = 1;
+
+ return 0;
+}
+__setup_param("earlycon", imx_keep_uart_earlycon,
+ imx_keep_uart_clocks_param, 0);
+__setup_param("earlyprintk", imx_keep_uart_earlyprintk,
+ imx_keep_uart_clocks_param, 0);
+
+void __init imx_register_uart_clocks(struct clk ** const clks[])
+{
+ if (imx_keep_uart_clocks) {
+ int i;
+
+ imx_uart_clocks = clks;
+ for (i = 0; imx_uart_clocks[i]; i++)
+ clk_prepare_enable(*imx_uart_clocks[i]);
+ }
+}
+
+static int __init imx_clk_disable_uart(void)
+{
+ if (imx_keep_uart_clocks && imx_uart_clocks) {
+ int i;
+
+ for (i = 0; imx_uart_clocks[i]; i++)
+ clk_disable_unprepare(*imx_uart_clocks[i]);
+ }
+
+ return 0;
+}
+late_initcall_sync(imx_clk_disable_uart);