ARM: OMAP: DSPGW: Deferred dsp initializtion

DSP HW-related initialization is deferred until the first DSP device
node is opened. This allows us to keep DSP powered down before the
DSP SW is loaded.
Signed-off-by: Hiroshi DOYU <Hiroshi.DOYU@nokia.com>
Signed-off-by: Juha Yrjola <juha.yrjola@solidboot.com>

arch/arm/plat-omap/dsp/dsp_common.c

@@ -305,8 +305,6 @@ static int __init omap_dsp_init(void)
 		return -ENODEV;
 	}
 
-	dsp_clk_autoidle();
-
 #if defined(CONFIG_ARCH_OMAP1)
 	dsp_ck_handle = clk_get(NULL, "dsp_ck");
 	if (IS_ERR(dsp_ck_handle)) {
@@ -347,12 +345,12 @@ static int __init omap_dsp_init(void)
 }
 
 #if defined(CONFIG_ARCH_OMAP1)
-static int dsp_late_init(void)
+static int __dsp_late_init(void)
 {
 	clk_disable(api_ck_handle);
 	return 0;
 }
-late_initcall(dsp_late_init);
+late_initcall(__dsp_late_init);
 #endif
 
 static void dsp_cpustat_update(void)

arch/arm/plat-omap/dsp/dsp_common.h

@@ -189,6 +189,7 @@ struct omap_dsp {
 	struct omap_mbox	*mbox;
 	struct device		*dev;
 	struct list_head 	*kdev_list;
+	int			initialized;
 };
 
 #if defined(CONFIG_ARCH_OMAP1)
@@ -203,4 +204,6 @@ struct omap_dsp {
 
 extern struct omap_dsp *omap_dsp;
 
+extern int dsp_late_init(void);
+
 #endif /* DRIVER_DSP_COMMON_H */

arch/arm/plat-omap/dsp/dsp_core.c

@@ -45,6 +45,8 @@ static struct sync_seq *mbseq;
 static u16 mbseq_expect_tmp;
 static u16 *mbseq_expect = &mbseq_expect_tmp;
 
+extern void dsp_mem_late_init(void);
+
 /*
  * mailbox commands
  */
@@ -511,6 +513,30 @@ static void mbox_kfunc(struct mbcmd *mb)
 	}
 }
 
+int dsp_late_init(void)
+{
+	int ret;
+
+	dsp_clk_autoidle();
+
+#ifdef CONFIG_ARCH_OMAP2
+	clk_enable(dsp_fck_handle);
+	clk_enable(dsp_ick_handle);
+	__dsp_per_enable();
+#endif
+	dsp_mem_late_init();
+
+#ifdef CONFIG_ARCH_OMAP1
+	dsp_set_idle_boot_base(IDLEPG_BASE, IDLEPG_SIZE);
+#endif
+	ret = dsp_kfunc_enable_devices(omap_dsp,
+				       DSP_KFUNC_DEV_TYPE_COMMON, 0);
+	if (ret == 0)
+		omap_dsp->enabled = 0;
+
+	return 0;
+}
+
 extern int  dsp_ctl_core_init(void);
 extern void dsp_ctl_core_exit(void);
 extern void dsp_ctl_init(void);
@@ -557,12 +583,6 @@ static int __init dsp_drv_probe(struct platform_device *pdev)
 		goto fail1;
 	}
 
-#ifdef CONFIG_ARCH_OMAP2
-	clk_enable(dsp_fck_handle);
-	clk_enable(dsp_ick_handle);
-	__dsp_per_enable();
-#endif
-
 	if ((ret = dsp_ctl_core_init()) < 0)
 		goto fail2;
 	if ((ret = dsp_mem_init()) < 0)
@@ -585,11 +605,6 @@ static int __init dsp_drv_probe(struct platform_device *pdev)
  fail3:
 	dsp_ctl_core_exit();
  fail2:
-#ifdef CONFIG_ARCH_OMAP2
-	__dsp_per_disable();
-	clk_disable(dsp_ick_handle);
-	clk_disable(dsp_fck_handle);
-#endif
  fail1:
 	dsp_kfunc_remove_devices(info);
  fail0:

arch/arm/plat-omap/dsp/dsp_ctl_core.c

@@ -40,6 +40,20 @@ extern struct file_operations dsp_ctl_fops,
 
 static int dsp_ctl_core_open(struct inode *inode, struct file *file)
 {
+	static DEFINE_MUTEX(open_lock);
+	int ret = 0;
+
+	mutex_lock_interruptible(&open_lock);
+	if (omap_dsp->initialized == 0) {
+		ret = dsp_late_init();
+		if (ret != 0) {
+			mutex_unlock(&open_lock);
+			return ret;
+		}
+		omap_dsp->initialized = 1;
+	}
+	mutex_unlock(&open_lock);
+
 	switch (iminor(inode)) {
 	case CTL_MINOR:
 		file->f_op = &dsp_ctl_fops;

arch/arm/plat-omap/dsp/dsp_mem.c

@@ -2453,24 +2453,32 @@ void dsp_mem_stop(void)
 #endif
 }
 
-static char devid_mmu;
-
-int __init dsp_mem_init(void)
+/*
+ * later half of dsp memory initialization
+ */
+void dsp_mem_late_init(void)
 {
-	int i;
-	int ret = 0;
 #ifdef CONFIG_ARCH_OMAP2
+	int i;
 	int dspmem_pg_count;
 
 	dspmem_pg_count = dspmem_size >> 12;
 	for (i = 0; i < dspmem_pg_count; i++) {
 		dsp_ipi_write_reg(i, DSP_IPI_INDEX);
-		dsp_ipi_write_reg(DSP_IPI_ENTRY_ELMSIZEVALUE_16, DSP_IPI_ENTRY);
+		dsp_ipi_write_reg(DSP_IPI_ENTRY_ELMSIZEVALUE_16,
+				  DSP_IPI_ENTRY);
 	}
 	dsp_ipi_write_reg(1, DSP_IPI_ENABLE);
-
 	dsp_ipi_write_reg(IOMAP_VAL, DSP_IPI_IOMAP);
 #endif
+	dsp_mmu_init();
+}
+
+static char devid_mmu;
+
+int __init dsp_mem_init(void)
+{
+	int i, ret;
 
 	for (i = 0; i < DSP_MMU_TLB_LINES; i++)
 		exmap_tbl[i].valid = 0;
@@ -2482,10 +2490,6 @@ int __init dsp_mem_init(void)
 		       "for dsp vector table\n");
 		return -ENOMEM;
 	}
-	dsp_mmu_init();
-#ifdef CONFIG_ARCH_OMAP1
-	dsp_set_idle_boot_base(IDLEPG_BASE, IDLEPG_SIZE);
-#endif
 
 	/*
 	 * DSP MMU interrupt setup
@@ -2495,7 +2499,7 @@ int __init dsp_mem_init(void)
 	if (ret) {
 		printk(KERN_ERR
 		       "failed to register DSP MMU interrupt: %d\n", ret);
-		goto fail;
+		return ret;
 	}
 
 	/* MMU interrupt is not enabled until DSP runs */
@@ -2506,15 +2510,6 @@ int __init dsp_mem_init(void)
 	device_create_file(omap_dsp->dev, &dev_attr_mempool);
 
 	return 0;
-
-fail:
-#ifdef CONFIG_ARCH_OMAP1
-	dsp_reset_idle_boot_base();
-#endif
-	dsp_mmu_shutdown();
-	free_page((unsigned long)dspvect_page);
-	dspvect_page = NULL;
-	return ret;
 }
 
 void dsp_mem_exit(void)