xref: /openbmc/u-boot/arch/arm/mach-imx/cache.c (revision 15e207fa)
1 // SPDX-License-Identifier: GPL-2.0+
2 /*
3  * Copyright 2015 Freescale Semiconductor, Inc.
4  */
5 
6 #include <common.h>
7 #include <asm/armv7.h>
8 #include <asm/pl310.h>
9 #include <asm/io.h>
10 #include <asm/mach-imx/sys_proto.h>
11 
12 static void enable_ca7_smp(void)
13 {
14 	u32 val;
15 
16 	/* Read MIDR */
17 	asm volatile ("mrc p15, 0, %0, c0, c0, 0\n\t" : "=r"(val));
18 	val = (val >> 4);
19 	val &= 0xf;
20 
21 	/* Only set the SMP for Cortex A7 */
22 	if (val == 0x7) {
23 		/* Read auxiliary control register */
24 		asm volatile ("mrc p15, 0, %0, c1, c0, 1\n\t" : "=r"(val));
25 
26 		if (val & (1 << 6))
27 			return;
28 
29 		/* Enable SMP */
30 		val |= (1 << 6);
31 
32 		/* Write auxiliary control register */
33 		asm volatile ("mcr p15, 0, %0, c1, c0, 1\n\t" : : "r"(val));
34 
35 		DSB;
36 		ISB;
37 	}
38 }
39 
40 #ifndef CONFIG_SYS_DCACHE_OFF
41 void enable_caches(void)
42 {
43 #if defined(CONFIG_SYS_ARM_CACHE_WRITETHROUGH)
44 	enum dcache_option option = DCACHE_WRITETHROUGH;
45 #else
46 	enum dcache_option option = DCACHE_WRITEBACK;
47 #endif
48 	/* Avoid random hang when download by usb */
49 	invalidate_dcache_all();
50 
51 	/* Set ACTLR.SMP bit for Cortex-A7 */
52 	enable_ca7_smp();
53 
54 	/* Enable D-cache. I-cache is already enabled in start.S */
55 	dcache_enable();
56 
57 	/* Enable caching on OCRAM and ROM */
58 	mmu_set_region_dcache_behaviour(ROMCP_ARB_BASE_ADDR,
59 					ROMCP_ARB_END_ADDR,
60 					option);
61 	mmu_set_region_dcache_behaviour(IRAM_BASE_ADDR,
62 					IRAM_SIZE,
63 					option);
64 }
65 #else
66 void enable_caches(void)
67 {
68 	/*
69 	 * Set ACTLR.SMP bit for Cortex-A7, even if the caches are
70 	 * disabled by u-boot
71 	 */
72 	enable_ca7_smp();
73 
74 	puts("WARNING: Caches not enabled\n");
75 }
76 #endif
77 
78 #ifndef CONFIG_SYS_L2CACHE_OFF
79 #ifdef CONFIG_SYS_L2_PL310
80 #define IOMUXC_GPR11_L2CACHE_AS_OCRAM 0x00000002
81 void v7_outer_cache_enable(void)
82 {
83 	struct pl310_regs *const pl310 = (struct pl310_regs *)L2_PL310_BASE;
84 	struct iomuxc *iomux = (struct iomuxc *)IOMUXC_BASE_ADDR;
85 	unsigned int val;
86 
87 
88 	/*
89 	 * Must disable the L2 before changing the latency parameters
90 	 * and auxiliary control register.
91 	 */
92 	clrbits_le32(&pl310->pl310_ctrl, L2X0_CTRL_EN);
93 
94 	/*
95 	 * Set bit 22 in the auxiliary control register. If this bit
96 	 * is cleared, PL310 treats Normal Shared Non-cacheable
97 	 * accesses as Cacheable no-allocate.
98 	 */
99 	setbits_le32(&pl310->pl310_aux_ctrl, L310_SHARED_ATT_OVERRIDE_ENABLE);
100 
101 	if (is_mx6sl() || is_mx6sll()) {
102 		val = readl(&iomux->gpr[11]);
103 		if (val & IOMUXC_GPR11_L2CACHE_AS_OCRAM) {
104 			/* L2 cache configured as OCRAM, reset it */
105 			val &= ~IOMUXC_GPR11_L2CACHE_AS_OCRAM;
106 			writel(val, &iomux->gpr[11]);
107 		}
108 	}
109 
110 	writel(0x132, &pl310->pl310_tag_latency_ctrl);
111 	writel(0x132, &pl310->pl310_data_latency_ctrl);
112 
113 	val = readl(&pl310->pl310_prefetch_ctrl);
114 
115 	/* Turn on the L2 I/D prefetch */
116 	val |= 0x30000000;
117 
118 	/*
119 	 * The L2 cache controller(PL310) version on the i.MX6D/Q is r3p1-50rel0
120 	 * The L2 cache controller(PL310) version on the i.MX6DL/SOLO/SL is r3p2
121 	 * But according to ARM PL310 errata: 752271
122 	 * ID: 752271: Double linefill feature can cause data corruption
123 	 * Fault Status: Present in: r3p0, r3p1, r3p1-50rel0. Fixed in r3p2
124 	 * Workaround: The only workaround to this erratum is to disable the
125 	 * double linefill feature. This is the default behavior.
126 	 */
127 
128 #ifndef CONFIG_MX6Q
129 	val |= 0x40800000;
130 #endif
131 	writel(val, &pl310->pl310_prefetch_ctrl);
132 
133 	val = readl(&pl310->pl310_power_ctrl);
134 	val |= L2X0_DYNAMIC_CLK_GATING_EN;
135 	val |= L2X0_STNDBY_MODE_EN;
136 	writel(val, &pl310->pl310_power_ctrl);
137 
138 	setbits_le32(&pl310->pl310_ctrl, L2X0_CTRL_EN);
139 }
140 
141 void v7_outer_cache_disable(void)
142 {
143 	struct pl310_regs *const pl310 = (struct pl310_regs *)L2_PL310_BASE;
144 
145 	clrbits_le32(&pl310->pl310_ctrl, L2X0_CTRL_EN);
146 }
147 #endif /* !CONFIG_SYS_L2_PL310 */
148 #endif /* !CONFIG_SYS_L2CACHE_OFF */
149