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-rw-r--r--arch/arm/mach-msm/proc_comm.c110
1 files changed, 110 insertions, 0 deletions
diff --git a/arch/arm/mach-msm/proc_comm.c b/arch/arm/mach-msm/proc_comm.c
new file mode 100644
index 0000000..915ee70
--- /dev/null
+++ b/arch/arm/mach-msm/proc_comm.c
@@ -0,0 +1,110 @@
+/* arch/arm/mach-msm/proc_comm.c
+ *
+ * Copyright (C) 2007-2008 Google, Inc.
+ * Author: Brian Swetland <swetland@google.com>
+ *
+ * This software is licensed under the terms of the GNU General Public
+ * License version 2, as published by the Free Software Foundation, and
+ * may be copied, distributed, and modified under those terms.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ */
+
+#include <linux/delay.h>
+#include <linux/errno.h>
+#include <linux/io.h>
+#include <linux/spinlock.h>
+#include <mach/msm_iomap.h>
+#include <mach/system.h>
+
+#include "proc_comm.h"
+
+#define MSM_A2M_INT(n) (MSM_CSR_BASE + 0x400 + (n) * 4)
+
+static inline void notify_other_proc_comm(void)
+{
+ writel(1, MSM_A2M_INT(6));
+}
+
+#define APP_COMMAND 0x00
+#define APP_STATUS 0x04
+#define APP_DATA1 0x08
+#define APP_DATA2 0x0C
+
+#define MDM_COMMAND 0x10
+#define MDM_STATUS 0x14
+#define MDM_DATA1 0x18
+#define MDM_DATA2 0x1C
+
+static DEFINE_SPINLOCK(proc_comm_lock);
+
+/* The higher level SMD support will install this to
+ * provide a way to check for and handle modem restart.
+ */
+int (*msm_check_for_modem_crash)(void);
+
+/* Poll for a state change, checking for possible
+ * modem crashes along the way (so we don't wait
+ * forever while the ARM9 is blowing up).
+ *
+ * Return an error in the event of a modem crash and
+ * restart so the msm_proc_comm() routine can restart
+ * the operation from the beginning.
+ */
+static int proc_comm_wait_for(void __iomem *addr, unsigned value)
+{
+ for (;;) {
+ if (readl(addr) == value)
+ return 0;
+
+ if (msm_check_for_modem_crash)
+ if (msm_check_for_modem_crash())
+ return -EAGAIN;
+ }
+}
+
+int msm_proc_comm(unsigned cmd, unsigned *data1, unsigned *data2)
+{
+ void __iomem *base = MSM_SHARED_RAM_BASE;
+ unsigned long flags;
+ int ret;
+
+ spin_lock_irqsave(&proc_comm_lock, flags);
+
+ for (;;) {
+ if (proc_comm_wait_for(base + MDM_STATUS, PCOM_READY))
+ continue;
+
+ writel(cmd, base + APP_COMMAND);
+ writel(data1 ? *data1 : 0, base + APP_DATA1);
+ writel(data2 ? *data2 : 0, base + APP_DATA2);
+
+ notify_other_proc_comm();
+
+ if (proc_comm_wait_for(base + APP_COMMAND, PCOM_CMD_DONE))
+ continue;
+
+ if (readl(base + APP_STATUS) != PCOM_CMD_FAIL) {
+ if (data1)
+ *data1 = readl(base + APP_DATA1);
+ if (data2)
+ *data2 = readl(base + APP_DATA2);
+ ret = 0;
+ } else {
+ ret = -EIO;
+ }
+ break;
+ }
+
+ writel(PCOM_CMD_IDLE, base + APP_COMMAND);
+
+ spin_unlock_irqrestore(&proc_comm_lock, flags);
+
+ return ret;
+}
+
+
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