[RFC v5 25/26] m68k/mac: Fix PRAM accessors

Finn Thain
2015-07-25T07:46:24Z

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Signed-off-by: Finn Thain <fthain@telegraphics.com.au>

---

Tested on a PowerBook 520 and Quadra 650.

Changes since v2:
- Make use of the RTC_* macros from the previous patch and add a few more
besides.

---
arch/m68k/mac/misc.c | 39 +++++++++++++++++++++++++++++++++------
include/uapi/linux/pmu.h | 2 ++
2 files changed, 35 insertions(+), 6 deletions(-)

Index: linux/arch/m68k/mac/misc.c
===================================================================
--- linux.orig/arch/m68k/mac/misc.c 2015-07-25 17:45:54.000000000 +1000
+++ linux/arch/m68k/mac/misc.c 2015-07-25 17:45:55.000000000 +1000
@@ -119,19 +119,22 @@ static void pmu_write_time(long data)
static unsigned char pmu_pram_read_byte(int offset)
{
struct adb_request req;
- if (pmu_request(&req, NULL, 3, PMU_READ_NVRAM,
- (offset >> 8) & 0xFF, offset & 0xFF) < 0)
+
+ if (pmu_request(&req, NULL, 3, PMU_READ_XPRAM,
+ offset & 0xFF, 1) < 0)
return 0;
while (!req.complete)
pmu_poll();
- return req.reply[3];
+
+ return req.reply[1];
}

static void pmu_pram_write_byte(unsigned char data, int offset)
{
struct adb_request req;
- if (pmu_request(&req, NULL, 4, PMU_WRITE_NVRAM,
- (offset >> 8) & 0xFF, offset & 0xFF, data) < 0)
+
+ if (pmu_request(&req, NULL, 4, PMU_WRITE_XPRAM,
+ offset & 0xFF, 1, data) < 0)
return;
while (!req.complete)
pmu_poll();
@@ -257,6 +260,16 @@ static void via_rtc_send(__u8 data)
#define RTC_REG_WRITE_PROTECT 13

/*
+ * Inside Mac has no information about two-byte RTC commands but
+ * the MESS source code has the essentials.
+ */
+
+#define RTC_REG_XPRAM 14
+#define RTC_CMD_XPRAM_READ (RTC_CMD_READ(RTC_REG_XPRAM) << 8)
+#define RTC_CMD_XPRAM_WRITE (RTC_CMD_WRITE(RTC_REG_XPRAM) << 8)
+#define RTC_CMD_XPRAM_ARG(a) (((a & 0xE0) << 3) | ((a & 0x1F) << 2))
+
+/*
* Execute a VIA PRAM/RTC command. For read commands
* data should point to a one-byte buffer for the
* resulting data. For write commands it should point
@@ -303,11 +316,25 @@ static void via_rtc_command(int command,

static unsigned char via_pram_read_byte(int offset)
{
- return 0;
+ unsigned char temp;
+
+ via_rtc_command(RTC_CMD_XPRAM_READ | RTC_CMD_XPRAM_ARG(offset), &temp);
+
+ return temp;
}

static void via_pram_write_byte(unsigned char data, int offset)
{
+ unsigned char temp;
+
+ temp = 0x55;
+ via_rtc_command(RTC_CMD_WRITE(RTC_REG_WRITE_PROTECT), &temp);
+
+ temp = data;
+ via_rtc_command(RTC_CMD_XPRAM_WRITE | RTC_CMD_XPRAM_ARG(offset), &temp);
+
+ temp = 0x55 | RTC_FLG_WRITE_PROTECT;
+ via_rtc_command(RTC_CMD_WRITE(RTC_REG_WRITE_PROTECT), &temp);
}

/*
Index: linux/include/uapi/linux/pmu.h
===================================================================
--- linux.orig/include/uapi/linux/pmu.h 2015-07-25 17:42:33.000000000 +1000
+++ linux/include/uapi/linux/pmu.h 2015-07-25 17:45:55.000000000 +1000
@@ -18,7 +18,9 @@
#define PMU_POWER_CTRL 0x11 /* control power of some devices */
#define PMU_ADB_CMD 0x20 /* send ADB packet */
#define PMU_ADB_POLL_OFF 0x21 /* disable ADB auto-poll */
+#define PMU_WRITE_XPRAM 0x32 /* write eXtended Parameter RAM */
#define PMU_WRITE_NVRAM 0x33 /* write non-volatile RAM */
+#define PMU_READ_XPRAM 0x3a /* read eXtended Parameter RAM */
#define PMU_READ_NVRAM 0x3b /* read non-volatile RAM */
#define PMU_SET_RTC 0x30 /* set real-time clock */
#define PMU_READ_RTC 0x38 /* read real-time clock */