Merge tag 'fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/arm...
[linux-2.6.git] / arch / arm / mach-msm / proc_comm.c
blob507f5ca806977343ae688a058ecb96131b8e0797
1 /* arch/arm/mach-msm/proc_comm.c
3 * Copyright (C) 2007-2008 Google, Inc.
4 * Author: Brian Swetland <swetland@google.com>
6 * This software is licensed under the terms of the GNU General Public
7 * License version 2, as published by the Free Software Foundation, and
8 * may be copied, distributed, and modified under those terms.
10 * This program is distributed in the hope that it will be useful,
11 * but WITHOUT ANY WARRANTY; without even the implied warranty of
12 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
13 * GNU General Public License for more details.
17 #include <linux/delay.h>
18 #include <linux/errno.h>
19 #include <linux/io.h>
20 #include <linux/spinlock.h>
21 #include <mach/msm_iomap.h>
23 #include "proc_comm.h"
25 static inline void msm_a2m_int(uint32_t irq)
27 #if defined(CONFIG_ARCH_MSM7X30)
28 writel(1 << irq, MSM_GCC_BASE + 0x8);
29 #else
30 writel(1, MSM_CSR_BASE + 0x400 + (irq * 4));
31 #endif
34 static inline void notify_other_proc_comm(void)
36 msm_a2m_int(6);
39 #define APP_COMMAND 0x00
40 #define APP_STATUS 0x04
41 #define APP_DATA1 0x08
42 #define APP_DATA2 0x0C
44 #define MDM_COMMAND 0x10
45 #define MDM_STATUS 0x14
46 #define MDM_DATA1 0x18
47 #define MDM_DATA2 0x1C
49 static DEFINE_SPINLOCK(proc_comm_lock);
51 /* The higher level SMD support will install this to
52 * provide a way to check for and handle modem restart.
54 int (*msm_check_for_modem_crash)(void);
56 /* Poll for a state change, checking for possible
57 * modem crashes along the way (so we don't wait
58 * forever while the ARM9 is blowing up).
60 * Return an error in the event of a modem crash and
61 * restart so the msm_proc_comm() routine can restart
62 * the operation from the beginning.
64 static int proc_comm_wait_for(void __iomem *addr, unsigned value)
66 for (;;) {
67 if (readl(addr) == value)
68 return 0;
70 if (msm_check_for_modem_crash)
71 if (msm_check_for_modem_crash())
72 return -EAGAIN;
76 int msm_proc_comm(unsigned cmd, unsigned *data1, unsigned *data2)
78 void __iomem *base = MSM_SHARED_RAM_BASE;
79 unsigned long flags;
80 int ret;
82 spin_lock_irqsave(&proc_comm_lock, flags);
84 for (;;) {
85 if (proc_comm_wait_for(base + MDM_STATUS, PCOM_READY))
86 continue;
88 writel(cmd, base + APP_COMMAND);
89 writel(data1 ? *data1 : 0, base + APP_DATA1);
90 writel(data2 ? *data2 : 0, base + APP_DATA2);
92 notify_other_proc_comm();
94 if (proc_comm_wait_for(base + APP_COMMAND, PCOM_CMD_DONE))
95 continue;
97 if (readl(base + APP_STATUS) != PCOM_CMD_FAIL) {
98 if (data1)
99 *data1 = readl(base + APP_DATA1);
100 if (data2)
101 *data2 = readl(base + APP_DATA2);
102 ret = 0;
103 } else {
104 ret = -EIO;
106 break;
109 writel(PCOM_CMD_IDLE, base + APP_COMMAND);
111 spin_unlock_irqrestore(&proc_comm_lock, flags);
113 return ret;
117 * We need to wait for the ARM9 to at least partially boot
118 * up before we can continue. Since the ARM9 does resource
119 * allocation, if we dont' wait we could end up crashing or in
120 * and unknown state. This function should be called early to
121 * wait on the ARM9.
123 void proc_comm_boot_wait(void)
125 void __iomem *base = MSM_SHARED_RAM_BASE;
127 proc_comm_wait_for(base + MDM_STATUS, PCOM_READY);