arm: msm: smd: fix SMD modem processor sync condition

When booting up we need to wait for the modem processor to
partially boot. This is because the modem processor does
resource allocation for us. If we don't wait the modem won't
honor our requests and we end up crashing or in an unknown
state. This change just formalizes the waiting process.

Signed-off-by: Daniel Walker <c_dwalke@quicinc.com>

3 files changed, 24 insertions, 1 deletions

diff --git a/arch/arm/mach-msm/proc_comm.c b/arch/arm/mach-msm/proc_comm.c
index 1cbdebf57c37..67e701c7f183 100644
--- a/arch/arm/mach-msm/proc_comm.c
+++ b/arch/arm/mach-msm/proc_comm.c
@@ -114,4 +114,17 @@ int msm_proc_comm(unsigned cmd, unsigned *data1, unsigned *data2)
         return ret;
 }
 
-
+/*
+ * We need to wait for the ARM9 to at least partially boot
+ * up before we can continue. Since the ARM9 does resource
+ * allocation, if we dont' wait we could end up crashing or in
+ * and unknown state. This function should be called early to
+ * wait on the ARM9.
+ */
+void __init proc_comm_boot_wait(void)
+{
+        void __iomem *base = MSM_SHARED_RAM_BASE;
+ 
+        proc_comm_wait_for(base + MDM_STATUS, PCOM_READY);
+ 
+}
diff --git a/arch/arm/mach-msm/proc_comm.h b/arch/arm/mach-msm/proc_comm.h
index 0f5cdd345eb7..12da4cacd4a8 100644
--- a/arch/arm/mach-msm/proc_comm.h
+++ b/arch/arm/mach-msm/proc_comm.h
@@ -16,6 +16,8 @@
 #ifndef _ARCH_ARM_MACH_MSM_PROC_COMM_H_
 #define _ARCH_ARM_MACH_MSM_PROC_COMM_H_
 
+#include <linux/init.h>
+
 enum {
         PCOM_CMD_IDLE = 0x0,
         PCOM_CMD_DONE,
@@ -251,5 +253,6 @@ enum {
                 (((drvstr) & 0xF) << 17))
 
 int msm_proc_comm(unsigned cmd, unsigned *data1, unsigned *data2);
+void __init proc_comm_boot_wait(void);
 
 #endif
diff --git a/arch/arm/mach-msm/smd.c b/arch/arm/mach-msm/smd.c
index de9343ec5cff..cf11d414b425 100644
--- a/arch/arm/mach-msm/smd.c
+++ b/arch/arm/mach-msm/smd.c
@@ -1001,6 +1001,13 @@ static int __init msm_smd_probe(struct platform_device *pdev)
 {
         pr_info("smd_init()\n");
 
+        /*
+         * If we haven't waited for the ARM9 to boot up till now,
+         * then we need to wait here. Otherwise this should just
+         * return immediately.
+         */
+        proc_comm_boot_wait();
+
         INIT_WORK(&probe_work, smd_channel_probe_worker);
 
         if (smd_core_init()) {