/* 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 "proc_comm.h" static inline void msm_a2m_int(uint32_t irq) { #if defined(CONFIG_ARCH_MSM7X30) writel(1 << irq, MSM_GCC_BASE + 0x8); #else writel(1, MSM_CSR_BASE + 0x400 + (irq * 4)); #endif } static inline void notify_other_proc_comm(void) { 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; } /* * 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 proc_comm_boot_wait(void) { void __iomem *base = MSM_SHARED_RAM_BASE; proc_comm_wait_for(base + MDM_STATUS, PCOM_READY); }