Revert "arm: tegra: clock: Reading APB bus before disabling clock"

This reverts commit 9b2aa51a8b4913948e3061706498c7f91d5aa827.

Change-Id: Ie197a9822329c7e36735ef673d0baf69923197de
Reviewed-on: http://git-master/r/34389
Reviewed-by: Niket Sirsi <nsirsi@nvidia.com>
Tested-by: Niket Sirsi <nsirsi@nvidia.com>

1 files changed, 27 insertions, 47 deletions

diff --git a/arch/arm/mach-tegra/tegra2_clocks.c b/arch/arm/mach-tegra/tegra2_clocks.c
index 6ae398bdb3f4..46d9c684c9ed 100644
--- a/arch/arm/mach-tegra/tegra2_clocks.c
+++ b/arch/arm/mach-tegra/tegra2_clocks.c
@@ -154,9 +154,6 @@
 
 static void __iomem *reg_clk_base = IO_ADDRESS(TEGRA_CLK_RESET_BASE);
 static void __iomem *reg_pmc_base = IO_ADDRESS(TEGRA_PMC_BASE);
-static void __iomem *misc_gp_hidrev_base = IO_ADDRESS(TEGRA_APB_MISC_BASE);
-
-#define MISC_GP_HIDREV			0x804
 
 /*
  * Some peripheral clocks share an enable bit, so refcount the enable bits
@@ -172,8 +169,6 @@ static int tegra_periph_clk_enable_refcount[3 * 32];
 	__raw_writel(value, (u32)reg_pmc_base + (reg))
 #define pmc_readl(reg) \
 	__raw_readl((u32)reg_pmc_base + (reg))
-#define chipid_readl() \
-	__raw_readl((u32)misc_gp_hidrev_base + MISC_GP_HIDREV)
 
 unsigned long clk_measure_input_freq(void)
 {
@@ -957,22 +952,14 @@ static int tegra2_periph_clk_enable(struct clk *c)
 
 static void tegra2_periph_clk_disable(struct clk *c)
 {
-	unsigned long val;
 	pr_debug("%s on clock %s\n", __func__, c->name);
 
 	if (c->refcnt)
 		tegra_periph_clk_enable_refcount[c->u.periph.clk_num]--;
 
-	if (tegra_periph_clk_enable_refcount[c->u.periph.clk_num] == 0) {
-		/* If peripheral is in the APB bus then read the APB bus to
-		 * flush the write operation in apb bus. This will avoid the
-		 * peripheral access after disabling clock*/
-		if (c->flags & PERIPH_ON_APB)
-			val = chipid_readl();
-
+	if (tegra_periph_clk_enable_refcount[c->u.periph.clk_num] == 0)
 		clk_writel(PERIPH_CLK_TO_ENB_BIT(c),
 			CLK_OUT_ENB_CLR + PERIPH_CLK_TO_ENB_SET_REG(c));
-	}
 }
 
 static void tegra2_periph_clk_reset(struct clk *c, bool assert)
@@ -981,16 +968,9 @@ static void tegra2_periph_clk_reset(struct clk *c, bool assert)
 
 	pr_debug("%s %s on clock %s\n", __func__,
 		 assert ? "assert" : "deassert", c->name);
-	if (!(c->flags & PERIPH_NO_RESET)) {
-		/* If peripheral is in the APB bus then read the APB bus to
-		 * flush the write operation in apb bus. This will avoid the
-		 * peripheral access after disabling clock*/
-		if (c->flags & PERIPH_ON_APB)
-			val = chipid_readl();
-
+	if (!(c->flags & PERIPH_NO_RESET))
 		clk_writel(PERIPH_CLK_TO_ENB_BIT(c),
 			   base + PERIPH_CLK_TO_ENB_SET_REG(c));
-	}
 }
 
 static int tegra2_periph_clk_set_parent(struct clk *c, struct clk *p)
@@ -2094,25 +2074,25 @@ static struct clk tegra_clk_emc = {
 
 struct clk tegra_list_periph_clks[] = {
 	PERIPH_CLK("apbdma",	 "apbdma",	     "apbdma",	34,	0,	0x31E,	26000000,  mux_clk_m,			0),
-	PERIPH_CLK("rtc",	"rtc-tegra",		NULL,	4,	0,	0x31E,	32768,     mux_clk_32k,			PERIPH_NO_RESET | PERIPH_ON_APB),
-	PERIPH_CLK("kbc",	"tegra-kbc",		NULL,	36, 	0,	0x31E,	32768,	   mux_clk_32k, PERIPH_NO_RESET | PERIPH_ON_APB),
+	PERIPH_CLK("rtc",	"rtc-tegra",		NULL,	4,	0,	0x31E,	32768,     mux_clk_32k,			PERIPH_NO_RESET),
+	PERIPH_CLK("kbc",	"tegra-kbc",		NULL,	36, 	0,	0x31E,	32768,	   mux_clk_32k, PERIPH_NO_RESET),
 	PERIPH_CLK("timer",	"timer",		NULL,	5,	0,	0x31E,	26000000,  mux_clk_m,			0),
 	PERIPH_CLK("kfuse",	"kfuse-tegra",		NULL,	40,	0,	0x31E,  26000000,  mux_clk_m,			0),
-	PERIPH_CLK("i2s1",	"i2s.0",		NULL,	11,	0x100,	0x31E,	26000000,  mux_pllaout0_audio2x_pllp_clkm,	MUX | DIV_U71 | PERIPH_ON_APB),
-	PERIPH_CLK("i2s2",	"i2s.1",		NULL,	18,	0x104,	0x31E,	26000000,  mux_pllaout0_audio2x_pllp_clkm,	MUX | DIV_U71 | PERIPH_ON_APB),
-	PERIPH_CLK("spdif_out",	"spdif_out",		NULL,	10,	0x108,	0x31E,	100000000, mux_pllaout0_audio2x_pllp_clkm,	MUX | DIV_U71 | PERIPH_ON_APB),
-	PERIPH_CLK("spdif_in",	"spdif_in",		NULL,	10,	0x10c,	0x31E,	100000000, mux_pllp_pllc_pllm,		MUX | DIV_U71 | PERIPH_ON_APB),
-	PERIPH_CLK("pwm",	"pwm",			NULL,	17,	0x110,	0x71C,	432000000, mux_pllp_pllc_audio_clkm_clk32,	MUX | DIV_U71 | PERIPH_ON_APB),
-	PERIPH_CLK("spi",	"spi",			NULL,	43,	0x114,	0x31E,	40000000,  mux_pllp_pllc_pllm_clkm,	MUX | DIV_U71 | PERIPH_ON_APB),
+	PERIPH_CLK("i2s1",	"i2s.0",		NULL,	11,	0x100,	0x31E,	26000000,  mux_pllaout0_audio2x_pllp_clkm,	MUX | DIV_U71),
+	PERIPH_CLK("i2s2",	"i2s.1",		NULL,	18,	0x104,	0x31E,	26000000,  mux_pllaout0_audio2x_pllp_clkm,	MUX | DIV_U71),
+	PERIPH_CLK("spdif_out",	"spdif_out",		NULL,	10,	0x108,	0x31E,	100000000, mux_pllaout0_audio2x_pllp_clkm,	MUX | DIV_U71),
+	PERIPH_CLK("spdif_in",	"spdif_in",		NULL,	10,	0x10c,	0x31E,	100000000, mux_pllp_pllc_pllm,		MUX | DIV_U71),
+	PERIPH_CLK("pwm",	"pwm",			NULL,	17,	0x110,	0x71C,	432000000, mux_pllp_pllc_audio_clkm_clk32,	MUX | DIV_U71),
+	PERIPH_CLK("spi",	"spi",			NULL,	43,	0x114,	0x31E,	40000000,  mux_pllp_pllc_pllm_clkm,	MUX | DIV_U71),
 	PERIPH_CLK("xio",	"xio",			NULL,	45,	0x120,	0x31E,	150000000, mux_pllp_pllc_pllm_clkm,	MUX | DIV_U71),
-	PERIPH_CLK("twc",	"twc",			NULL,	16,	0x12c,	0x31E,	150000000, mux_pllp_pllc_pllm_clkm,	MUX | DIV_U71 | PERIPH_ON_APB),
-	PERIPH_CLK("sbc1",	"spi_tegra.0",		NULL,	41,	0x134,	0x31E,	160000000, mux_pllp_pllc_pllm_clkm,	MUX | DIV_U71 | PERIPH_ON_APB),
-	PERIPH_CLK("sbc2",	"spi_tegra.1",		NULL,	44,	0x118,	0x31E,	160000000, mux_pllp_pllc_pllm_clkm,	MUX | DIV_U71 | PERIPH_ON_APB),
-	PERIPH_CLK("sbc3",	"spi_tegra.2",		NULL,	46,	0x11c,	0x31E,	160000000, mux_pllp_pllc_pllm_clkm,	MUX | DIV_U71 | PERIPH_ON_APB),
-	PERIPH_CLK("sbc4",	"spi_tegra.3",		NULL,	68,	0x1b4,	0x31E,	160000000, mux_pllp_pllc_pllm_clkm,	MUX | DIV_U71 | PERIPH_ON_APB),
+	PERIPH_CLK("twc",	"twc",			NULL,	16,	0x12c,	0x31E,	150000000, mux_pllp_pllc_pllm_clkm,	MUX | DIV_U71),
+	PERIPH_CLK("sbc1",	"spi_tegra.0",		NULL,	41,	0x134,	0x31E,	160000000, mux_pllp_pllc_pllm_clkm,	MUX | DIV_U71),
+	PERIPH_CLK("sbc2",	"spi_tegra.1",		NULL,	44,	0x118,	0x31E,	160000000, mux_pllp_pllc_pllm_clkm,	MUX | DIV_U71),
+	PERIPH_CLK("sbc3",	"spi_tegra.2",		NULL,	46,	0x11c,	0x31E,	160000000, mux_pllp_pllc_pllm_clkm,	MUX | DIV_U71),
+	PERIPH_CLK("sbc4",	"spi_tegra.3",		NULL,	68,	0x1b4,	0x31E,	160000000, mux_pllp_pllc_pllm_clkm,	MUX | DIV_U71),
 	PERIPH_CLK("ide",	"ide",			NULL,	25,	0x144,	0x31E,	100000000, mux_pllp_pllc_pllm_clkm,	MUX | DIV_U71), /* requires min voltage */
 	PERIPH_CLK("ndflash",	"tegra_nand",		NULL,	13,	0x160,	0x31E,	164000000, mux_pllp_pllc_pllm_clkm,	MUX | DIV_U71), /* scales with voltage */
-	PERIPH_CLK("vfir",	"vfir",			NULL,	7,	0x168,	0x31E,	72000000,  mux_pllp_pllc_pllm_clkm,	MUX | DIV_U71 | PERIPH_ON_APB),
+	PERIPH_CLK("vfir",	"vfir",			NULL,	7,	0x168,	0x31E,	72000000,  mux_pllp_pllc_pllm_clkm,	MUX | DIV_U71),
 	PERIPH_CLK("sdmmc1",	"sdhci-tegra.0",	NULL,	14,	0x150,	0x31E,	52000000,  mux_pllp_pllc_pllm_clkm,	MUX | DIV_U71), /* scales with voltage */
 	PERIPH_CLK("sdmmc2",	"sdhci-tegra.1",	NULL,	9,	0x154,	0x31E,	52000000,  mux_pllp_pllc_pllm_clkm,	MUX | DIV_U71), /* scales with voltage */
 	PERIPH_CLK("sdmmc3",	"sdhci-tegra.2",	NULL,	69,	0x1bc,	0x31E,	52000000,  mux_pllp_pllc_pllm_clkm,	MUX | DIV_U71), /* scales with voltage */
@@ -2124,18 +2104,18 @@ struct clk tegra_list_periph_clks[] = {
 	PERIPH_CLK("csite",	"csite",		NULL,	73,	0x1d4,	0x31E,	144000000, mux_pllp_pllc_pllm_clkm,	MUX | DIV_U71), /* max rate ??? */
 	/* FIXME: what is la? */
 	PERIPH_CLK("la",	"la",			NULL,	76,	0x1f8,	0x31E,	26000000,  mux_pllp_pllc_pllm_clkm,	MUX | DIV_U71),
-	PERIPH_CLK("owr",	"tegra_w1",		NULL,	71,	0x1cc,	0x31E,	26000000,  mux_pllp_pllc_pllm_clkm,	MUX | DIV_U71 | PERIPH_ON_APB),
+	PERIPH_CLK("owr",	"tegra_w1",		NULL,	71,	0x1cc,	0x31E,	26000000,  mux_pllp_pllc_pllm_clkm,	MUX | DIV_U71),
 	PERIPH_CLK("nor",	"nor",			NULL,	42,	0x1d0,	0x31E,	92000000,  mux_pllp_pllc_pllm_clkm,	MUX | DIV_U71), /* requires min voltage */
-	PERIPH_CLK("mipi",	"mipi",			NULL,	50,	0x174,	0x31E,	60000000,  mux_pllp_pllc_pllm_clkm,	MUX | DIV_U71 | PERIPH_ON_APB), /* scales with voltage */
-	PERIPH_CLK("i2c1",	"tegra-i2c.0",		NULL,	12,	0x124,	0x31E,	26000000,  mux_pllp_pllc_pllm_clkm,	MUX | DIV_U16 | PERIPH_ON_APB),
-	PERIPH_CLK("i2c2",	"tegra-i2c.1",		NULL,	54,	0x198,	0x31E,	26000000,  mux_pllp_pllc_pllm_clkm,	MUX | DIV_U16 | PERIPH_ON_APB),
-	PERIPH_CLK("i2c3",	"tegra-i2c.2",		NULL,	67,	0x1b8,	0x31E,	26000000,  mux_pllp_pllc_pllm_clkm,	MUX | DIV_U16 | PERIPH_ON_APB),
-	PERIPH_CLK("dvc",	"tegra-i2c.3",		NULL,	47,	0x128,	0x31E,	26000000,  mux_pllp_pllc_pllm_clkm,	MUX | DIV_U16 | PERIPH_ON_APB),
-	PERIPH_CLK("uarta",	"uart.0",		NULL,	6,	0x178,	0x31E,	600000000, mux_pllp_pllc_pllm_clkm,	MUX | PERIPH_ON_APB),
-	PERIPH_CLK("uartb",	"uart.1",		NULL,	7,	0x17c,	0x31E,	600000000, mux_pllp_pllc_pllm_clkm,	MUX | PERIPH_ON_APB),
-	PERIPH_CLK("uartc",	"uart.2",		NULL,	55,	0x1a0,	0x31E,	600000000, mux_pllp_pllc_pllm_clkm,	MUX | PERIPH_ON_APB),
-	PERIPH_CLK("uartd",	"uart.3",		NULL,	65,	0x1c0,	0x31E,	600000000, mux_pllp_pllc_pllm_clkm,	MUX | PERIPH_ON_APB),
-	PERIPH_CLK("uarte",	"uart.4",		NULL,	66,	0x1c4,	0x31E,	600000000, mux_pllp_pllc_pllm_clkm,	MUX | PERIPH_ON_APB),
+	PERIPH_CLK("mipi",	"mipi",			NULL,	50,	0x174,	0x31E,	60000000,  mux_pllp_pllc_pllm_clkm,	MUX | DIV_U71), /* scales with voltage */
+	PERIPH_CLK("i2c1",	"tegra-i2c.0",		NULL,	12,	0x124,	0x31E,	26000000,  mux_pllp_pllc_pllm_clkm,	MUX | DIV_U16),
+	PERIPH_CLK("i2c2",	"tegra-i2c.1",		NULL,	54,	0x198,	0x31E,	26000000,  mux_pllp_pllc_pllm_clkm,	MUX | DIV_U16),
+	PERIPH_CLK("i2c3",	"tegra-i2c.2",		NULL,	67,	0x1b8,	0x31E,	26000000,  mux_pllp_pllc_pllm_clkm,	MUX | DIV_U16),
+	PERIPH_CLK("dvc",	"tegra-i2c.3",		NULL,	47,	0x128,	0x31E,	26000000,  mux_pllp_pllc_pllm_clkm,	MUX | DIV_U16),
+	PERIPH_CLK("uarta",	"uart.0",		NULL,	6,	0x178,	0x31E,	600000000, mux_pllp_pllc_pllm_clkm,	MUX),
+	PERIPH_CLK("uartb",	"uart.1",		NULL,	7,	0x17c,	0x31E,	600000000, mux_pllp_pllc_pllm_clkm,	MUX),
+	PERIPH_CLK("uartc",	"uart.2",		NULL,	55,	0x1a0,	0x31E,	600000000, mux_pllp_pllc_pllm_clkm,	MUX),
+	PERIPH_CLK("uartd",	"uart.3",		NULL,	65,	0x1c0,	0x31E,	600000000, mux_pllp_pllc_pllm_clkm,	MUX),
+	PERIPH_CLK("uarte",	"uart.4",		NULL,	66,	0x1c4,	0x31E,	600000000, mux_pllp_pllc_pllm_clkm,	MUX),
 	PERIPH_CLK("3d",	"3d",			NULL,	24,	0x158,	0x31E,	300000000, mux_pllm_pllc_pllp_plla,	MUX | DIV_U71 | PERIPH_MANUAL_RESET), /* scales with voltage and process_id */
 	PERIPH_CLK("2d",	"2d",			NULL,	21,	0x15c,	0x31E,	300000000, mux_pllm_pllc_pllp_plla,	MUX | DIV_U71), /* scales with voltage and process_id */
 	PERIPH_CLK("vi",	"tegra_camera",		"vi",	20,	0x148,	0x31E,	150000000, mux_pllm_pllc_pllp_plla,	MUX | DIV_U71), /* scales with voltage and process_id */