ARM: OMAP2+: Fix imprecise external abort caused by bogus SRAM init

Some omaps are producing imprecise external aborts because we are
wrongly trying to init SRAM for device tree based booting. Only
omap3 is still using the legacy SRAM code, so we need to make it
omap3 specific. Otherwise we can get errors like this on at least
dm814x:

Unhandled fault: imprecise external abort (0xc06) at 0xc08b156c
...
(omap_rev) from [<c08b12e0>] (omap_sram_init+0xf8/0x3e0)
(omap_sram_init) from [<c08aca0c>] (omap_sdrc_init+0x10/0xb0)
(omap_sdrc_init) from [<c08b581c>] (pdata_quirks_init+0x18/0x44)
(pdata_quirks_init) from [<c08b5478>] (omap_generic_init+0x10/0x1c)
(omap_generic_init) from [<c08a57e0>] (customize_machine+0x1c/0x40)
(customize_machine) from [<c00098a4>] (do_one_initcall+0x80/0x1dc)
(do_one_initcall) from [<c08a2ec4>] (kernel_init_freeable+0x218/0x2e8)
(kernel_init_freeable) from [<c063a554>] (kernel_init+0x8/0xec)
(kernel_init) from [<c000f890>] (ret_from_fork+0x14/0x24)

Let's fix the issue by making sure omap_sdrc_init only gets called for
omap3. To do that, we need to have compatible "ti,omap3" in the dts
files. And let's also use "ti,omap3630" instead of "ti,omap36xx" like
we're supposed to.

Signed-off-by: Tony Lindgren <tony@atomide.com>

arch/arm/boot/dts/logicpd-torpedo-37xx-devkit.dts

@@ -12,7 +12,7 @@
 
 / {
 	model = "LogicPD Zoom DM3730 Torpedo Development Kit";
-	compatible = "logicpd,dm3730-torpedo-devkit", "ti,omap36xx";
+	compatible = "logicpd,dm3730-torpedo-devkit", "ti,omap3630", "ti,omap3";
 
 	gpio_keys {
 		compatible = "gpio-keys";

arch/arm/boot/dts/omap3-evm-37xx.dts

@@ -13,7 +13,7 @@
 
 / {
 	model = "TI OMAP37XX EVM (TMDSEVM3730)";
-	compatible = "ti,omap3-evm-37xx", "ti,omap36xx";
+	compatible = "ti,omap3-evm-37xx", "ti,omap3630", "ti,omap3";
 
 	memory {
 		device_type = "memory";

arch/arm/mach-omap2/board-generic.c

@@ -106,6 +106,7 @@ DT_MACHINE_START(OMAP3_DT, "Generic OMAP3 (Flattened Device Tree)")
 MACHINE_END
 
 static const char *const omap36xx_boards_compat[] __initconst = {
+	"ti,omap3630",
 	"ti,omap36xx",
 	NULL,
 };

arch/arm/mach-omap2/pdata-quirks.c

@@ -559,7 +559,14 @@ static void pdata_quirks_check(struct pdata_init *quirks)
 
 void __init pdata_quirks_init(const struct of_device_id *omap_dt_match_table)
 {
-	omap_sdrc_init(NULL, NULL);
+	/*
+	 * We still need this for omap2420 and omap3 PM to work, others are
+	 * using drivers/misc/sram.c already.
+	 */
+	if (of_machine_is_compatible("ti,omap2420") ||
+	    of_machine_is_compatible("ti,omap3"))
+		omap_sdrc_init(NULL, NULL);
+
 	pdata_quirks_check(auxdata_quirks);
 	of_platform_populate(NULL, omap_dt_match_table,
 			     omap_auxdata_lookup, NULL);