imx: mx6: Add plugin support

Add mx6_plugin.S which calls boot rom setup function, generate the second ivt,
and jump back to boot rom.

Signed-off-by: Peng Fan <peng.fan@nxp.com>
Signed-off-by: Ye Li <ye.li@nxp.com>
Signed-off-by: Utkarsh Gupta <utkarsh.gupta@nxp.com>
Reviewed-by: Tom Rini <trini@konsulko.com>
Acked-by: Utkarsh Gupta <utkarsh.gupta@nxp.com>

arch/arm/include/asm/arch-mx6/mx6_plugin.S

@@ -0,0 +1,159 @@
+/*
+ * Copyright (C) 2016 Freescale Semiconductor, Inc.
+ *
+ * SPDX-License-Identifier:	GPL-2.0+
+ */
+
+#include <config.h>
+
+#ifdef CONFIG_ROM_UNIFIED_SECTIONS
+#define ROM_API_TABLE_BASE_ADDR_LEGACY		0x180
+#define ROM_VERSION_OFFSET               	0x80
+#else
+#define ROM_API_TABLE_BASE_ADDR_LEGACY		0xC0
+#define ROM_VERSION_OFFSET               	0x48
+#endif
+#define ROM_API_TABLE_BASE_ADDR_MX6DQ_TO15	0xC4
+#define ROM_API_TABLE_BASE_ADDR_MX6DL_TO12	0xC4
+#define ROM_API_HWCNFG_SETUP_OFFSET		0x08
+#define ROM_VERSION_TO10			0x10
+#define ROM_VERSION_TO12			0x12
+#define ROM_VERSION_TO15			0x15
+
+plugin_start:
+
+	push    {r0-r4, lr}
+
+	imx6_ddr_setting
+	imx6_clock_gating
+	imx6_qos_setting
+
+/*
+ * The following is to fill in those arguments for this ROM function
+ * pu_irom_hwcnfg_setup(void **start, size_t *bytes, const void *boot_data)
+ * This function is used to copy data from the storage media into DDR.
+ * start - Initial (possibly partial) image load address on entry.
+ *         Final image load address on exit.
+ * bytes - Initial (possibly partial) image size on entry.
+ *         Final image size on exit.
+ * boot_data - Initial @ref ivt Boot Data load address.
+ */
+	adr r0, boot_data2
+	adr r1, image_len2
+	adr r2, boot_data2
+
+#ifdef CONFIG_NOR_BOOT
+#ifdef CONFIG_MX6SX
+	ldr r3, =ROM_VERSION_OFFSET
+	ldr r4, [r3]
+	cmp r4, #ROM_VERSION_TO10
+	bgt before_calling_rom___pu_irom_hwcnfg_setup
+	ldr r3, =0x00900b00
+	ldr r4, =0x50000000
+	str r4, [r3, #0x5c]
+#else
+	ldr r3, =0x00900800
+	ldr r4, =0x08000000
+	str r4, [r3, #0xc0]
+#endif
+#endif
+
+/*
+ * check the _pu_irom_api_table for the address
+ */
+before_calling_rom___pu_irom_hwcnfg_setup:
+	ldr r3, =ROM_VERSION_OFFSET
+	ldr r4, [r3]
+#if defined(CONFIG_MX6SOLO) || defined(CONFIG_MX6DL)
+	ldr r3, =ROM_VERSION_TO12
+	cmp r4, r3
+	ldrge r3, =ROM_API_TABLE_BASE_ADDR_MX6DL_TO12
+	ldrlt r3, =ROM_API_TABLE_BASE_ADDR_LEGACY
+#elif defined(CONFIG_MX6Q)
+	ldr r3, =ROM_VERSION_TO15
+	cmp r4, r3
+	ldrge r3, =ROM_API_TABLE_BASE_ADDR_MX6DQ_TO15
+	ldrlt r3, =ROM_API_TABLE_BASE_ADDR_LEGACY
+#else
+	ldr r3, =ROM_API_TABLE_BASE_ADDR_LEGACY
+#endif
+	ldr r4, [r3, #ROM_API_HWCNFG_SETUP_OFFSET]
+	blx r4
+after_calling_rom___pu_irom_hwcnfg_setup:
+
+/*
+ * ROM_API_HWCNFG_SETUP function enables MMU & Caches.
+ * Thus disable MMU & Caches.
+ */
+
+	mrc     p15, 0, r0, c1, c0, 0   /* read CP15 register 1 into r0*/
+	ands    r0, r0, #0x1            /* check if MMU is enabled */
+	beq     mmu_disable_notreq      /* exit if MMU is already disabled */
+
+	/* Disable caches, MMU */
+	mrc     p15, 0, r0, c1, c0, 0	/* read CP15 register 1 into r0 */
+	bic     r0, r0, #(1 << 2)	/* disable D Cache */
+	bic     r0, r0, #0x1		/* clear bit 0 ; MMU off */
+
+	bic     r0, r0, #(0x1 << 11)	/* disable Z, branch prediction */
+	bic     r0, r0, #(0x1 << 1)	/* disable A, Strict alignment */
+					/* check enabled. */
+	mcr     p15, 0, r0, c1, c0, 0	/* write CP15 register 1 */
+	mov     r0, r0
+	mov     r0, r0
+	mov     r0, r0
+	mov     r0, r0
+
+mmu_disable_notreq:
+    NOP
+
+/* To return to ROM from plugin, we need to fill in these argument.
+ * Here is what need to do:
+ * Need to construct the paramters for this function before return to ROM:
+ * plugin_download(void **start, size_t *bytes, UINT32 *ivt_offset)
+ */
+	pop {r0-r4, lr}
+	push {r5}
+	ldr r5, boot_data2
+	str r5, [r0]
+	ldr r5, image_len2
+	str r5, [r1]
+	ldr r5, second_ivt_offset
+	str r5, [r2]
+	mov r0, #1
+	pop {r5}
+
+	/* return back to ROM code */
+	bx lr
+
+/* make the following data right in the end of the output*/
+.ltorg
+
+#if (defined(CONFIG_NOR_BOOT) || defined(CONFIG_QSPI_BOOT))
+#define FLASH_OFFSET 0x1000
+#else
+#define FLASH_OFFSET 0x400
+#endif
+
+/*
+ * second_ivt_offset is the offset from the "second_ivt_header" to
+ * "image_copy_start", which involves FLASH_OFFSET, plus the first
+ * ivt_header, the plugin code size itself recorded by "ivt2_header"
+ */
+
+second_ivt_offset:      .long (ivt2_header + 0x2C + FLASH_OFFSET)
+
+/*
+ * The following is the second IVT header plus the second boot data
+ */
+ivt2_header:            .long 0x0
+app2_code_jump_v:       .long 0x0
+reserv3:                .long 0x0
+dcd2_ptr:               .long 0x0
+boot_data2_ptr:         .long 0x0
+self_ptr2:              .long 0x0
+app_code_csf2:          .long 0x0
+reserv4:                .long 0x0
+boot_data2:             .long 0x0
+image_len2:             .long 0x0
+plugin2:                .long 0x0