[U-Boot] [PATCH v2 04/11] x86: rtc: mc146818: Add helpers to read/write CMOS RAM

[Simon Glass]

On x86 we use CMOS RAM to read and write some settings. Add basic support
for this, including access to registers 128-255.

Signed-off-by: Simon Glass <sjg at chromium.org>
---

Changes in v2:
- Adjust the mc146818 driver instead of adding a new cmos.h header

 drivers/rtc/mc146818.c | 53 +++++++++++++++++++++++++++++++++++++-------------
 include/rtc.h          | 32 ++++++++++++++++++++++++++++++
 2 files changed, 71 insertions(+), 14 deletions(-)

diff --git a/drivers/rtc/mc146818.c b/drivers/rtc/mc146818.c
index 39e6041..b506b16 100644
--- a/drivers/rtc/mc146818.c
+++ b/drivers/rtc/mc146818.c
@@ -27,9 +27,6 @@
 /* Set this to 1 to clear the CMOS RAM */
 #define CLEAR_CMOS 0
 
-static uchar rtc_read  (uchar reg);
-static void  rtc_write (uchar reg, uchar val);
-
 #define RTC_PORT_MC146818	CONFIG_SYS_ISA_IO_BASE_ADDRESS +  0x70
 #define RTC_SECONDS		0x00
 #define RTC_SECONDS_ALARM	0x01
@@ -133,32 +130,60 @@ void rtc_reset (void)
 
 /* ------------------------------------------------------------------------- */
 
-#ifdef CONFIG_SYS_RTC_REG_BASE_ADDR
 /*
  * use direct memory access
  */
-static uchar rtc_read (uchar reg)
+int rtc_read(int reg)
 {
+#ifdef CONFIG_SYS_RTC_REG_BASE_ADDR
 	return in8(CONFIG_SYS_RTC_REG_BASE_ADDR + reg);
+#else
+	int ofs = 0;
+
+	if (reg >= 128) {
+		ofs = 2;
+		reg -= 128;
+	}
+	out8(RTC_PORT_MC146818 + ofs, reg);
+
+	return in8(RTC_PORT_MC146818 + ofs + 1);
+#endif
 }
 
-static void rtc_write (uchar reg, uchar val)
+void rtc_write(int reg, uchar val)
 {
+#ifdef CONFIG_SYS_RTC_REG_BASE_ADDR
 	out8(CONFIG_SYS_RTC_REG_BASE_ADDR + reg, val);
-}
 #else
-static uchar rtc_read (uchar reg)
+	int ofs = 0;
+
+	if (reg >= 128) {
+		ofs = 2;
+		reg -= 128;
+	}
+	out8(RTC_PORT_MC146818 + ofs, reg);
+	out8(RTC_PORT_MC146818 + ofs + 1, val);
+#endif
+}
+
+u32 rtc_read32(int reg)
 {
-	out8(RTC_PORT_MC146818,reg);
-	return in8(RTC_PORT_MC146818 + 1);
+	u32 value = 0;
+	int i;
+
+	for (i = 0; i < sizeof(value); i++)
+		value |= rtc_read(reg + i) << (i << 3);
+
+	return value;
 }
 
-static void rtc_write (uchar reg, uchar val)
+void rtc_write32(int reg, u32 value)
 {
-	out8(RTC_PORT_MC146818,reg);
-	out8(RTC_PORT_MC146818+1, val);
+	int i;
+
+	for (i = 0; i < sizeof(value); i++)
+		rtc_write(reg + i, (value >> (i << 3)) & 0xff);
 }
-#endif
 
 void rtc_init(void)
 {
diff --git a/include/rtc.h b/include/rtc.h
index d11aa8b..b6df1f4 100644
--- a/include/rtc.h
+++ b/include/rtc.h
@@ -51,6 +51,38 @@ unsigned long mktime (unsigned int, unsigned int, unsigned int,
 		      unsigned int, unsigned int, unsigned int);
 
 /**
+ * rtc_read() - Read an 8-bit register
+ *
+ * @reg:	Register to read
+ * @return value read
+ */
+int rtc_read(int reg);
+
+/**
+ * rtc_write() - Write an 8-bit register
+ *
+ * @reg:	Register to write
+ * @value:	Value to write
+ */
+void rtc_write(int reg, uchar val);
+
+/**
+ * rtc_read32() - Read a 32-bit value from the RTC
+ *
+ * @reg:	Offset to start reading from
+ * @return value read
+ */
+u32 rtc_read32(int reg);
+
+/**
+ * rtc_write32() - Write a 32-bit value to the RTC
+ *
+ * @reg:	Register to start writing to
+ * @value:	Value to write
+ */
+void rtc_write32(int reg, u32 value);
+
+/**
  * rtc_init() - Set up the real time clock ready for use
  */
 void rtc_init(void);
-- 
2.2.0.rc0.207.ga3a616c