openpower/linux/0010-drm-ast-POST-code-for-the-new-AST2500.patch

From 0000000000000000000000000000000000000000 Mon Sep 17 00:00:00 2001
From: "Y.C. Chen" <yc_chen@aspeedtech.com>
Date: Fri, 17 Feb 2017 14:45:07 +1100
Subject: [PATCH 10/12] drm/ast: POST code for the new AST2500

This is used when the BMC isn't running any code and thus has
to be initialized by the host.

The code originates from Aspeed (Y.C. Chen) and has been cleaned
up for coding style purposes by BenH.

Signed-off-by: Y.C. Chen <yc_chen@aspeedtech.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
--

v2. - Fix bug in ddr_test_2500 reported by Emil Velikov
    - Rebase on updated mmc_test factoring patch
    - Fix missing else statement in 2500 POST code

Signed-off-by: Joel Stanley <joel@jms.id.au>
---
 drivers/gpu/drm/ast/ast_dram_tables.h |  62 +++++
 drivers/gpu/drm/ast/ast_post.c        | 417 +++++++++++++++++++++++++++++++++-
 2 files changed, 476 insertions(+), 3 deletions(-)

diff --git a/drivers/gpu/drm/ast/ast_dram_tables.h b/drivers/gpu/drm/ast/ast_dram_tables.h
index cc04539c0ff3..1d9c4e75d303 100644
--- a/drivers/gpu/drm/ast/ast_dram_tables.h
+++ b/drivers/gpu/drm/ast/ast_dram_tables.h
@@ -141,4 +141,66 @@ static const struct ast_dramstruct ast2100_dram_table_data[] = {
 	{ 0xffff, 0xffffffff },
 };
 
+/*
+ * AST2500 DRAM settings modules
+ */
+#define REGTBL_NUM           17
+#define REGIDX_010           0
+#define REGIDX_014           1
+#define REGIDX_018           2
+#define REGIDX_020           3
+#define REGIDX_024           4
+#define REGIDX_02C           5
+#define REGIDX_030           6
+#define REGIDX_214           7
+#define REGIDX_2E0           8
+#define REGIDX_2E4           9
+#define REGIDX_2E8           10
+#define REGIDX_2EC           11
+#define REGIDX_2F0           12
+#define REGIDX_2F4           13
+#define REGIDX_2F8           14
+#define REGIDX_RFC           15
+#define REGIDX_PLL           16
+
+static const u32 ast2500_ddr3_1600_timing_table[REGTBL_NUM] = {
+	0x64604D38,		     /* 0x010 */
+	0x29690599,		     /* 0x014 */
+	0x00000300,		     /* 0x018 */
+	0x00000000,		     /* 0x020 */
+	0x00000000,		     /* 0x024 */
+	0x02181E70,		     /* 0x02C */
+	0x00000040,		     /* 0x030 */
+	0x00000024,		     /* 0x214 */
+	0x02001300,		     /* 0x2E0 */
+	0x0E0000A0,		     /* 0x2E4 */
+	0x000E001B,		     /* 0x2E8 */
+	0x35B8C105,		     /* 0x2EC */
+	0x08090408,		     /* 0x2F0 */
+	0x9B000800,		     /* 0x2F4 */
+	0x0E400A00,		     /* 0x2F8 */
+	0x9971452F,		     /* tRFC  */
+	0x000071C1		     /* PLL   */
+};
+
+static const u32 ast2500_ddr4_1600_timing_table[REGTBL_NUM] = {
+	0x63604E37,		     /* 0x010 */
+	0xE97AFA99,		     /* 0x014 */
+	0x00019000,		     /* 0x018 */
+	0x08000000,		     /* 0x020 */
+	0x00000400,		     /* 0x024 */
+	0x00000410,		     /* 0x02C */
+	0x00000101,		     /* 0x030 */
+	0x00000024,		     /* 0x214 */
+	0x03002900,		     /* 0x2E0 */
+	0x0E0000A0,		     /* 0x2E4 */
+	0x000E001C,		     /* 0x2E8 */
+	0x35B8C106,		     /* 0x2EC */
+	0x08080607,		     /* 0x2F0 */
+	0x9B000900,		     /* 0x2F4 */
+	0x0E400A00,		     /* 0x2F8 */
+	0x99714545,		     /* tRFC  */
+	0x000071C1		     /* PLL   */
+};
+
 #endif
diff --git a/drivers/gpu/drm/ast/ast_post.c b/drivers/gpu/drm/ast/ast_post.c
index 3716795d27c8..f7d421359d56 100644
--- a/drivers/gpu/drm/ast/ast_post.c
+++ b/drivers/gpu/drm/ast/ast_post.c
@@ -32,6 +32,7 @@
 #include "ast_dram_tables.h"
 
 static void ast_post_chip_2300(struct drm_device *dev);
+static void ast_post_chip_2500(struct drm_device *dev);
 
 void ast_enable_vga(struct drm_device *dev)
 {
@@ -78,7 +79,8 @@ ast_set_def_ext_reg(struct drm_device *dev)
 	for (i = 0x81; i <= 0x9f; i++)
 		ast_set_index_reg(ast, AST_IO_CRTC_PORT, i, 0x00);
 
-	if (ast->chip == AST2300 || ast->chip == AST2400) {
+	if (ast->chip == AST2300 || ast->chip == AST2400 ||
+	    ast->chip == AST2500) {
 		if (dev->pdev->revision >= 0x20)
 			ext_reg_info = extreginfo_ast2300;
 		else
@@ -102,7 +104,8 @@ ast_set_def_ext_reg(struct drm_device *dev)
 
 	/* Enable RAMDAC for A1 */
 	reg = 0x04;
-	if (ast->chip == AST2300 || ast->chip == AST2400)
+	if (ast->chip == AST2300 || ast->chip == AST2400 ||
+	    ast->chip == AST2500)
 		reg |= 0x20;
 	ast_set_index_reg_mask(ast, AST_IO_CRTC_PORT, 0xb6, 0xff, reg);
 }
@@ -376,7 +379,9 @@ void ast_post_gpu(struct drm_device *dev)
 	ast_set_def_ext_reg(dev);
 
 	if (ast->config_mode == ast_use_p2a) {
-		if (ast->chip == AST2300 || ast->chip == AST2400)
+		if (ast->chip == AST2500)
+			ast_post_chip_2500(dev);
+		else if (ast->chip == AST2300 || ast->chip == AST2400)
 			ast_post_chip_2300(dev);
 		else
 			ast_init_dram_reg(dev);
@@ -502,6 +507,11 @@ static u32 mmc_test_single2(struct ast_private *ast, u32 datagen)
 	return mmc_test2(ast, datagen, 0x05);
 }
 
+static bool mmc_test_single_2500(struct ast_private *ast, u32 datagen)
+{
+	return mmc_test(ast, datagen, 0x85);
+}
+
 static int cbr_test(struct ast_private *ast)
 {
 	u32 data;
@@ -1668,3 +1678,404 @@ static void ast_post_chip_2300(struct drm_device *dev)
 	} while ((reg & 0x40) == 0);
 }
 
+static bool cbr_test_2500(struct ast_private *ast)
+{
+	ast_moutdwm(ast, 0x1E6E0074, 0x0000FFFF);
+	ast_moutdwm(ast, 0x1E6E007C, 0xFF00FF00);
+	if (!mmc_test_burst(ast, 0))
+		return false;
+	if (!mmc_test_single_2500(ast, 0))
+		return false;
+	return true;
+}
+
+static bool ddr_test_2500(struct ast_private *ast)
+{
+	ast_moutdwm(ast, 0x1E6E0074, 0x0000FFFF);
+	ast_moutdwm(ast, 0x1E6E007C, 0xFF00FF00);
+	if (!mmc_test_burst(ast, 0))
+		return false;
+	if (!mmc_test_burst(ast, 1))
+		return false;
+	if (!mmc_test_burst(ast, 2))
+		return false;
+	if (!mmc_test_burst(ast, 3))
+		return false;
+	if (!mmc_test_single_2500(ast, 0))
+		return false;
+	return true;
+}
+
+static void ddr_init_common_2500(struct ast_private *ast)
+{
+	ast_moutdwm(ast, 0x1E6E0034, 0x00020080);
+	ast_moutdwm(ast, 0x1E6E0008, 0x2003000F);
+	ast_moutdwm(ast, 0x1E6E0038, 0x00000FFF);
+	ast_moutdwm(ast, 0x1E6E0040, 0x88448844);
+	ast_moutdwm(ast, 0x1E6E0044, 0x24422288);
+	ast_moutdwm(ast, 0x1E6E0048, 0x22222222);
+	ast_moutdwm(ast, 0x1E6E004C, 0x22222222);
+	ast_moutdwm(ast, 0x1E6E0050, 0x80000000);
+	ast_moutdwm(ast, 0x1E6E0208, 0x00000000);
+	ast_moutdwm(ast, 0x1E6E0218, 0x00000000);
+	ast_moutdwm(ast, 0x1E6E0220, 0x00000000);
+	ast_moutdwm(ast, 0x1E6E0228, 0x00000000);
+	ast_moutdwm(ast, 0x1E6E0230, 0x00000000);
+	ast_moutdwm(ast, 0x1E6E02A8, 0x00000000);
+	ast_moutdwm(ast, 0x1E6E02B0, 0x00000000);
+	ast_moutdwm(ast, 0x1E6E0240, 0x86000000);
+	ast_moutdwm(ast, 0x1E6E0244, 0x00008600);
+	ast_moutdwm(ast, 0x1E6E0248, 0x80000000);
+	ast_moutdwm(ast, 0x1E6E024C, 0x80808080);
+}
+
+static void ddr_phy_init_2500(struct ast_private *ast)
+{
+	u32 data, pass, timecnt;
+
+	pass = 0;
+	ast_moutdwm(ast, 0x1E6E0060, 0x00000005);
+	while (!pass) {
+		for (timecnt = 0; timecnt < TIMEOUT; timecnt++) {
+			data = ast_mindwm(ast, 0x1E6E0060) & 0x1;
+			if (!data)
+				break;
+		}
+		if (timecnt != TIMEOUT) {
+			data = ast_mindwm(ast, 0x1E6E0300) & 0x000A0000;
+			if (!data)
+				pass = 1;
+		}
+		if (!pass) {
+			ast_moutdwm(ast, 0x1E6E0060, 0x00000000);
+			udelay(10); /* delay 10 us */
+			ast_moutdwm(ast, 0x1E6E0060, 0x00000005);
+		}
+	}
+
+	ast_moutdwm(ast, 0x1E6E0060, 0x00000006);
+}
+
+/*
+ * Check DRAM Size
+ * 1Gb : 0x80000000 ~ 0x87FFFFFF
+ * 2Gb : 0x80000000 ~ 0x8FFFFFFF
+ * 4Gb : 0x80000000 ~ 0x9FFFFFFF
+ * 8Gb : 0x80000000 ~ 0xBFFFFFFF
+ */
+static void check_dram_size_2500(struct ast_private *ast, u32 tRFC)
+{
+	u32 reg_04, reg_14;
+
+	reg_04 = ast_mindwm(ast, 0x1E6E0004) & 0xfffffffc;
+	reg_14 = ast_mindwm(ast, 0x1E6E0014) & 0xffffff00;
+
+	ast_moutdwm(ast, 0xA0100000, 0x41424344);
+	ast_moutdwm(ast, 0x90100000, 0x35363738);
+	ast_moutdwm(ast, 0x88100000, 0x292A2B2C);
+	ast_moutdwm(ast, 0x80100000, 0x1D1E1F10);
+
+	/* Check 8Gbit */
+	if (ast_mindwm(ast, 0xA0100000) == 0x41424344) {
+		reg_04 |= 0x03;
+		reg_14 |= (tRFC >> 24) & 0xFF;
+		/* Check 4Gbit */
+	} else if (ast_mindwm(ast, 0x90100000) == 0x35363738) {
+		reg_04 |= 0x02;
+		reg_14 |= (tRFC >> 16) & 0xFF;
+		/* Check 2Gbit */
+	} else if (ast_mindwm(ast, 0x88100000) == 0x292A2B2C) {
+		reg_04 |= 0x01;
+		reg_14 |= (tRFC >> 8) & 0xFF;
+	} else {
+		reg_14 |= tRFC & 0xFF;
+	}
+	ast_moutdwm(ast, 0x1E6E0004, reg_04);
+	ast_moutdwm(ast, 0x1E6E0014, reg_14);
+}
+
+static void enable_cache_2500(struct ast_private *ast)
+{
+	u32 reg_04, data;
+
+	reg_04 = ast_mindwm(ast, 0x1E6E0004);
+	ast_moutdwm(ast, 0x1E6E0004, reg_04 | 0x1000);
+
+	do
+		data = ast_mindwm(ast, 0x1E6E0004);
+	while (!(data & 0x80000));
+	ast_moutdwm(ast, 0x1E6E0004, reg_04 | 0x400);
+}
+
+static void set_mpll_2500(struct ast_private *ast)
+{
+	u32 addr, data, param;
+
+	/* Reset MMC */
+	ast_moutdwm(ast, 0x1E6E0000, 0xFC600309);
+	ast_moutdwm(ast, 0x1E6E0034, 0x00020080);
+	for (addr = 0x1e6e0004; addr < 0x1e6e0090;) {
+		ast_moutdwm(ast, addr, 0x0);
+		addr += 4;
+	}
+	ast_moutdwm(ast, 0x1E6E0034, 0x00020000);
+
+	ast_moutdwm(ast, 0x1E6E2000, 0x1688A8A8);
+	data = ast_mindwm(ast, 0x1E6E2070) & 0x00800000;
+	if (data) {
+		/* CLKIN = 25MHz */
+		param = 0x930023E0;
+		ast_moutdwm(ast, 0x1E6E2160, 0x00011320);
+	} else {
+		/* CLKIN = 24MHz */
+		param = 0x93002400;
+	}
+	ast_moutdwm(ast, 0x1E6E2020, param);
+	udelay(100);
+}
+
+static void reset_mmc_2500(struct ast_private *ast)
+{
+	ast_moutdwm(ast, 0x1E78505C, 0x00000004);
+	ast_moutdwm(ast, 0x1E785044, 0x00000001);
+	ast_moutdwm(ast, 0x1E785048, 0x00004755);
+	ast_moutdwm(ast, 0x1E78504C, 0x00000013);
+	mdelay(100);
+	ast_moutdwm(ast, 0x1E785054, 0x00000077);
+	ast_moutdwm(ast, 0x1E6E0000, 0xFC600309);
+}
+
+static void ddr3_init_2500(struct ast_private *ast, const u32 *ddr_table)
+{
+
+	ast_moutdwm(ast, 0x1E6E0004, 0x00000303);
+	ast_moutdwm(ast, 0x1E6E0010, ddr_table[REGIDX_010]);
+	ast_moutdwm(ast, 0x1E6E0014, ddr_table[REGIDX_014]);
+	ast_moutdwm(ast, 0x1E6E0018, ddr_table[REGIDX_018]);
+	ast_moutdwm(ast, 0x1E6E0020, ddr_table[REGIDX_020]);	     /* MODEREG4/6 */
+	ast_moutdwm(ast, 0x1E6E0024, ddr_table[REGIDX_024]);	     /* MODEREG5 */
+	ast_moutdwm(ast, 0x1E6E002C, ddr_table[REGIDX_02C] | 0x100); /* MODEREG0/2 */
+	ast_moutdwm(ast, 0x1E6E0030, ddr_table[REGIDX_030]);	     /* MODEREG1/3 */
+
+	/* DDR PHY Setting */
+	ast_moutdwm(ast, 0x1E6E0200, 0x02492AAE);
+	ast_moutdwm(ast, 0x1E6E0204, 0x00001001);
+	ast_moutdwm(ast, 0x1E6E020C, 0x55E00B0B);
+	ast_moutdwm(ast, 0x1E6E0210, 0x20000000);
+	ast_moutdwm(ast, 0x1E6E0214, ddr_table[REGIDX_214]);
+	ast_moutdwm(ast, 0x1E6E02E0, ddr_table[REGIDX_2E0]);
+	ast_moutdwm(ast, 0x1E6E02E4, ddr_table[REGIDX_2E4]);
+	ast_moutdwm(ast, 0x1E6E02E8, ddr_table[REGIDX_2E8]);
+	ast_moutdwm(ast, 0x1E6E02EC, ddr_table[REGIDX_2EC]);
+	ast_moutdwm(ast, 0x1E6E02F0, ddr_table[REGIDX_2F0]);
+	ast_moutdwm(ast, 0x1E6E02F4, ddr_table[REGIDX_2F4]);
+	ast_moutdwm(ast, 0x1E6E02F8, ddr_table[REGIDX_2F8]);
+	ast_moutdwm(ast, 0x1E6E0290, 0x00100008);
+	ast_moutdwm(ast, 0x1E6E02C0, 0x00000006);
+
+	/* Controller Setting */
+	ast_moutdwm(ast, 0x1E6E0034, 0x00020091);
+
+	/* Wait DDR PHY init done */
+	ddr_phy_init_2500(ast);
+
+	ast_moutdwm(ast, 0x1E6E0120, ddr_table[REGIDX_PLL]);
+	ast_moutdwm(ast, 0x1E6E000C, 0x42AA5C81);
+	ast_moutdwm(ast, 0x1E6E0034, 0x0001AF93);
+
+	check_dram_size_2500(ast, ddr_table[REGIDX_RFC]);
+	enable_cache_2500(ast);
+	ast_moutdwm(ast, 0x1E6E001C, 0x00000008);
+	ast_moutdwm(ast, 0x1E6E0038, 0xFFFFFF00);
+}
+
+static void ddr4_init_2500(struct ast_private *ast, const u32 *ddr_table)
+{
+	u32 data, data2, pass, retrycnt;
+	u32 ddr_vref, phy_vref;
+	u32 min_ddr_vref = 0, min_phy_vref = 0;
+	u32 max_ddr_vref = 0, max_phy_vref = 0;
+
+	ast_moutdwm(ast, 0x1E6E0004, 0x00000313);
+	ast_moutdwm(ast, 0x1E6E0010, ddr_table[REGIDX_010]);
+	ast_moutdwm(ast, 0x1E6E0014, ddr_table[REGIDX_014]);
+	ast_moutdwm(ast, 0x1E6E0018, ddr_table[REGIDX_018]);
+	ast_moutdwm(ast, 0x1E6E0020, ddr_table[REGIDX_020]);	     /* MODEREG4/6 */
+	ast_moutdwm(ast, 0x1E6E0024, ddr_table[REGIDX_024]);	     /* MODEREG5 */
+	ast_moutdwm(ast, 0x1E6E002C, ddr_table[REGIDX_02C] | 0x100); /* MODEREG0/2 */
+	ast_moutdwm(ast, 0x1E6E0030, ddr_table[REGIDX_030]);	     /* MODEREG1/3 */
+
+	/* DDR PHY Setting */
+	ast_moutdwm(ast, 0x1E6E0200, 0x42492AAE);
+	ast_moutdwm(ast, 0x1E6E0204, 0x09002000);
+	ast_moutdwm(ast, 0x1E6E020C, 0x55E00B0B);
+	ast_moutdwm(ast, 0x1E6E0210, 0x20000000);
+	ast_moutdwm(ast, 0x1E6E0214, ddr_table[REGIDX_214]);
+	ast_moutdwm(ast, 0x1E6E02E0, ddr_table[REGIDX_2E0]);
+	ast_moutdwm(ast, 0x1E6E02E4, ddr_table[REGIDX_2E4]);
+	ast_moutdwm(ast, 0x1E6E02E8, ddr_table[REGIDX_2E8]);
+	ast_moutdwm(ast, 0x1E6E02EC, ddr_table[REGIDX_2EC]);
+	ast_moutdwm(ast, 0x1E6E02F0, ddr_table[REGIDX_2F0]);
+	ast_moutdwm(ast, 0x1E6E02F4, ddr_table[REGIDX_2F4]);
+	ast_moutdwm(ast, 0x1E6E02F8, ddr_table[REGIDX_2F8]);
+	ast_moutdwm(ast, 0x1E6E0290, 0x00100008);
+	ast_moutdwm(ast, 0x1E6E02C4, 0x3C183C3C);
+	ast_moutdwm(ast, 0x1E6E02C8, 0x00631E0E);
+
+	/* Controller Setting */
+	ast_moutdwm(ast, 0x1E6E0034, 0x0001A991);
+
+	/* Train PHY Vref first */
+	pass = 0;
+
+	for (retrycnt = 0; retrycnt < 4 && pass == 0; retrycnt++) {
+		max_phy_vref = 0x0;
+		pass = 0;
+		ast_moutdwm(ast, 0x1E6E02C0, 0x00001C06);
+		for (phy_vref = 0x40; phy_vref < 0x80; phy_vref++) {
+			ast_moutdwm(ast, 0x1E6E000C, 0x00000000);
+			ast_moutdwm(ast, 0x1E6E0060, 0x00000000);
+			ast_moutdwm(ast, 0x1E6E02CC, phy_vref | (phy_vref << 8));
+			/* Fire DFI Init */
+			ddr_phy_init_2500(ast);
+			ast_moutdwm(ast, 0x1E6E000C, 0x00005C01);
+			if (cbr_test_2500(ast)) {
+				pass++;
+				data = ast_mindwm(ast, 0x1E6E03D0);
+				data2 = data >> 8;
+				data  = data & 0xff;
+				if (data > data2)
+					data = data2;
+				if (max_phy_vref < data) {
+					max_phy_vref = data;
+					min_phy_vref = phy_vref;
+				}
+			} else if (pass > 0)
+				break;
+		}
+	}
+	ast_moutdwm(ast, 0x1E6E02CC, min_phy_vref | (min_phy_vref << 8));
+
+	/* Train DDR Vref next */
+	pass = 0;
+
+	for (retrycnt = 0; retrycnt < 4 && pass == 0; retrycnt++) {
+		min_ddr_vref = 0xFF;
+		max_ddr_vref = 0x0;
+		pass = 0;
+		for (ddr_vref = 0x00; ddr_vref < 0x40; ddr_vref++) {
+			ast_moutdwm(ast, 0x1E6E000C, 0x00000000);
+			ast_moutdwm(ast, 0x1E6E0060, 0x00000000);
+			ast_moutdwm(ast, 0x1E6E02C0, 0x00000006 | (ddr_vref << 8));
+			/* Fire DFI Init */
+			ddr_phy_init_2500(ast);
+			ast_moutdwm(ast, 0x1E6E000C, 0x00005C01);
+			if (cbr_test_2500(ast)) {
+				pass++;
+				if (min_ddr_vref > ddr_vref)
+					min_ddr_vref = ddr_vref;
+				if (max_ddr_vref < ddr_vref)
+					max_ddr_vref = ddr_vref;
+			} else if (pass != 0)
+				break;
+		}
+	}
+
+	ast_moutdwm(ast, 0x1E6E000C, 0x00000000);
+	ast_moutdwm(ast, 0x1E6E0060, 0x00000000);
+	ddr_vref = (min_ddr_vref + max_ddr_vref + 1) >> 1;
+	ast_moutdwm(ast, 0x1E6E02C0, 0x00000006 | (ddr_vref << 8));
+
+	/* Wait DDR PHY init done */
+	ddr_phy_init_2500(ast);
+
+	ast_moutdwm(ast, 0x1E6E0120, ddr_table[REGIDX_PLL]);
+	ast_moutdwm(ast, 0x1E6E000C, 0x42AA5C81);
+	ast_moutdwm(ast, 0x1E6E0034, 0x0001AF93);
+
+	check_dram_size_2500(ast, ddr_table[REGIDX_RFC]);
+	enable_cache_2500(ast);
+	ast_moutdwm(ast, 0x1E6E001C, 0x00000008);
+	ast_moutdwm(ast, 0x1E6E0038, 0xFFFFFF00);
+}
+
+static bool ast_dram_init_2500(struct ast_private *ast)
+{
+	u32 data;
+	u32 max_tries = 5;
+
+	do {
+		if (max_tries-- == 0)
+			return false;
+		set_mpll_2500(ast);
+		reset_mmc_2500(ast);
+		ddr_init_common_2500(ast);
+
+		data = ast_mindwm(ast, 0x1E6E2070);
+		if (data & 0x01000000)
+			ddr4_init_2500(ast, ast2500_ddr4_1600_timing_table);
+		else
+			ddr3_init_2500(ast, ast2500_ddr3_1600_timing_table);
+	} while (!ddr_test_2500(ast));
+
+	ast_moutdwm(ast, 0x1E6E2040, ast_mindwm(ast, 0x1E6E2040) | 0x41);
+
+	/* Patch code */
+	data = ast_mindwm(ast, 0x1E6E200C) & 0xF9FFFFFF;
+	ast_moutdwm(ast, 0x1E6E200C, data | 0x10000000);
+
+	return true;
+}
+
+void ast_post_chip_2500(struct drm_device *dev)
+{
+	struct ast_private *ast = dev->dev_private;
+	u32 temp;
+	u8 reg;
+
+	reg = ast_get_index_reg_mask(ast, AST_IO_CRTC_PORT, 0xd0, 0xff);
+	if ((reg & 0x80) == 0) {/* vga only */
+		/* Clear bus lock condition */
+		ast_moutdwm(ast, 0x1e600000, 0xAEED1A03);
+		ast_moutdwm(ast, 0x1e600084, 0x00010000);
+		ast_moutdwm(ast, 0x1e600088, 0x00000000);
+		ast_moutdwm(ast, 0x1e6e2000, 0x1688A8A8);
+		ast_write32(ast, 0xf004, 0x1e6e0000);
+		ast_write32(ast, 0xf000, 0x1);
+		ast_write32(ast, 0x12000, 0x1688a8a8);
+		while (ast_read32(ast, 0x12000) != 0x1)
+			;
+
+		ast_write32(ast, 0x10000, 0xfc600309);
+		while (ast_read32(ast, 0x10000) != 0x1)
+			;
+
+		/* Slow down CPU/AHB CLK in VGA only mode */
+		temp = ast_read32(ast, 0x12008);
+		temp |= 0x73;
+		ast_write32(ast, 0x12008, temp);
+
+		/* Reset USB port to patch USB unknown device issue */
+		ast_moutdwm(ast, 0x1e6e2090, 0x20000000);
+		temp  = ast_mindwm(ast, 0x1e6e2094);
+		temp |= 0x00004000;
+		ast_moutdwm(ast, 0x1e6e2094, temp);
+		temp  = ast_mindwm(ast, 0x1e6e2070);
+		if (temp & 0x00800000) {
+			ast_moutdwm(ast, 0x1e6e207c, 0x00800000);
+			mdelay(100);
+			ast_moutdwm(ast, 0x1e6e2070, 0x00800000);
+		}
+
+		if (!ast_dram_init_2500(ast))
+			DRM_ERROR("DRAM init failed !\n");
+
+		temp = ast_mindwm(ast, 0x1e6e2040);
+		ast_moutdwm(ast, 0x1e6e2040, temp | 0x40);
+	}
+
+	/* wait ready */
+	do {
+		reg = ast_get_index_reg_mask(ast, AST_IO_CRTC_PORT, 0xd0, 0xff);
+	} while ((reg & 0x40) == 0);
+}
-- 
2.11.0