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Tegra20: Move some code files to common directories for upcoming Tegra30 patches.
[people/ms/u-boot.git] / arch / arm / cpu / arm720t / tegra20 / cpu.c
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1/*
2* (C) Copyright 2010-2011
3* NVIDIA Corporation <www.nvidia.com>
4*
5* See file CREDITS for list of people who contributed to this
6* project.
7*
8* This program is free software; you can redistribute it and/or
9* modify it under the terms of the GNU General Public License as
10* published by the Free Software Foundation; either version 2 of
11* the License, or (at your option) any later version.
12*
13* This program is distributed in the hope that it will be useful,
14* but WITHOUT ANY WARRANTY; without even the implied warranty of
15* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
16* GNU General Public License for more details.
17*
18* You should have received a copy of the GNU General Public License
19* along with this program; if not, write to the Free Software
20* Foundation, Inc., 59 Temple Place, Suite 330, Boston,
21* MA 02111-1307 USA
22*/
23
24#include <asm/io.h>
25#include <asm/arch/tegra20.h>
26#include <asm/arch/clk_rst.h>
27#include <asm/arch/clock.h>
28#include <asm/arch/pmc.h>
29#include <asm/arch/pinmux.h>
30#include <asm/arch/scu.h>
31#include <common.h>
3064f322 32#include "../tegra-common/cpu.h"
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33
34/* Returns 1 if the current CPU executing is a Cortex-A9, else 0 */
35int ap20_cpu_is_cortexa9(void)
36{
37 u32 id = readb(NV_PA_PG_UP_BASE + PG_UP_TAG_0);
38 return id == (PG_UP_TAG_0_PID_CPU & 0xff);
39}
40
41void init_pllx(void)
42{
43 struct clk_rst_ctlr *clkrst = (struct clk_rst_ctlr *)NV_PA_CLK_RST_BASE;
44 struct clk_pll *pll = &clkrst->crc_pll[CLOCK_ID_XCPU];
45 u32 reg;
46
47 /* If PLLX is already enabled, just return */
48 if (readl(&pll->pll_base) & PLL_ENABLE_MASK)
49 return;
50
51 /* Set PLLX_MISC */
52 writel(1 << PLL_CPCON_SHIFT, &pll->pll_misc);
53
54 /* Use 12MHz clock here */
55 reg = PLL_BYPASS_MASK | (12 << PLL_DIVM_SHIFT);
56 reg |= 1000 << PLL_DIVN_SHIFT;
57 writel(reg, &pll->pll_base);
58
59 reg |= PLL_ENABLE_MASK;
60 writel(reg, &pll->pll_base);
61
62 reg &= ~PLL_BYPASS_MASK;
63 writel(reg, &pll->pll_base);
64}
65
66static void enable_cpu_clock(int enable)
67{
68 struct clk_rst_ctlr *clkrst = (struct clk_rst_ctlr *)NV_PA_CLK_RST_BASE;
69 u32 clk;
70
71 /*
72 * NOTE:
73 * Regardless of whether the request is to enable or disable the CPU
74 * clock, every processor in the CPU complex except the master (CPU 0)
75 * will have it's clock stopped because the AVP only talks to the
76 * master. The AVP does not know (nor does it need to know) that there
77 * are multiple processors in the CPU complex.
78 */
79
80 if (enable) {
81 /* Initialize PLLX */
82 init_pllx();
83
84 /* Wait until all clocks are stable */
85 udelay(PLL_STABILIZATION_DELAY);
86
87 writel(CCLK_BURST_POLICY, &clkrst->crc_cclk_brst_pol);
88 writel(SUPER_CCLK_DIVIDER, &clkrst->crc_super_cclk_div);
89 }
90
91 /*
92 * Read the register containing the individual CPU clock enables and
93 * always stop the clock to CPU 1.
94 */
95 clk = readl(&clkrst->crc_clk_cpu_cmplx);
96 clk |= 1 << CPU1_CLK_STP_SHIFT;
97
98 /* Stop/Unstop the CPU clock */
99 clk &= ~CPU0_CLK_STP_MASK;
100 clk |= !enable << CPU0_CLK_STP_SHIFT;
101 writel(clk, &clkrst->crc_clk_cpu_cmplx);
102
103 clock_enable(PERIPH_ID_CPU);
104}
105
106static int is_cpu_powered(void)
107{
29f3e3f2 108 struct pmc_ctlr *pmc = (struct pmc_ctlr *)NV_PA_PMC_BASE;
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109
110 return (readl(&pmc->pmc_pwrgate_status) & CPU_PWRED) ? 1 : 0;
111}
112
113static void remove_cpu_io_clamps(void)
114{
29f3e3f2 115 struct pmc_ctlr *pmc = (struct pmc_ctlr *)NV_PA_PMC_BASE;
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116 u32 reg;
117
118 /* Remove the clamps on the CPU I/O signals */
119 reg = readl(&pmc->pmc_remove_clamping);
120 reg |= CPU_CLMP;
121 writel(reg, &pmc->pmc_remove_clamping);
122
123 /* Give I/O signals time to stabilize */
124 udelay(IO_STABILIZATION_DELAY);
125}
126
127static void powerup_cpu(void)
128{
29f3e3f2 129 struct pmc_ctlr *pmc = (struct pmc_ctlr *)NV_PA_PMC_BASE;
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130 u32 reg;
131 int timeout = IO_STABILIZATION_DELAY;
132
133 if (!is_cpu_powered()) {
134 /* Toggle the CPU power state (OFF -> ON) */
135 reg = readl(&pmc->pmc_pwrgate_toggle);
136 reg &= PARTID_CP;
137 reg |= START_CP;
138 writel(reg, &pmc->pmc_pwrgate_toggle);
139
140 /* Wait for the power to come up */
141 while (!is_cpu_powered()) {
142 if (timeout-- == 0)
143 printf("CPU failed to power up!\n");
144 else
145 udelay(10);
146 }
147
148 /*
149 * Remove the I/O clamps from CPU power partition.
150 * Recommended only on a Warm boot, if the CPU partition gets
151 * power gated. Shouldn't cause any harm when called after a
152 * cold boot according to HW, probably just redundant.
153 */
154 remove_cpu_io_clamps();
155 }
156}
157
158static void enable_cpu_power_rail(void)
159{
29f3e3f2 160 struct pmc_ctlr *pmc = (struct pmc_ctlr *)NV_PA_PMC_BASE;
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161 u32 reg;
162
163 reg = readl(&pmc->pmc_cntrl);
164 reg |= CPUPWRREQ_OE;
165 writel(reg, &pmc->pmc_cntrl);
166
167 /*
168 * The TI PMU65861C needs a 3.75ms delay between enabling
169 * the power rail and enabling the CPU clock. This delay
170 * between SM1EN and SM1 is for switching time + the ramp
171 * up of the voltage to the CPU (VDD_CPU from PMU).
172 */
173 udelay(3750);
174}
175
176static void reset_A9_cpu(int reset)
177{
178 /*
179 * NOTE: Regardless of whether the request is to hold the CPU in reset
180 * or take it out of reset, every processor in the CPU complex
181 * except the master (CPU 0) will be held in reset because the
182 * AVP only talks to the master. The AVP does not know that there
183 * are multiple processors in the CPU complex.
184 */
185
186 /* Hold CPU 1 in reset, and CPU 0 if asked */
187 reset_cmplx_set_enable(1, crc_rst_cpu | crc_rst_de | crc_rst_debug, 1);
188 reset_cmplx_set_enable(0, crc_rst_cpu | crc_rst_de | crc_rst_debug,
189 reset);
190
191 /* Enable/Disable master CPU reset */
192 reset_set_enable(PERIPH_ID_CPU, reset);
193}
194
195static void clock_enable_coresight(int enable)
196{
197 u32 rst, src;
198
199 clock_set_enable(PERIPH_ID_CORESIGHT, enable);
200 reset_set_enable(PERIPH_ID_CORESIGHT, !enable);
201
202 if (enable) {
203 /*
204 * Put CoreSight on PLLP_OUT0 (216 MHz) and divide it down by
205 * 1.5, giving an effective frequency of 144MHz.
206 * Set PLLP_OUT0 [bits31:30 = 00], and use a 7.1 divisor
207 * (bits 7:0), so 00000001b == 1.5 (n+1 + .5)
208 */
209 src = CLK_DIVIDER(NVBL_PLLP_KHZ, 144000);
210 clock_ll_set_source_divisor(PERIPH_ID_CSI, 0, src);
211
212 /* Unlock the CPU CoreSight interfaces */
213 rst = 0xC5ACCE55;
214 writel(rst, CSITE_CPU_DBG0_LAR);
215 writel(rst, CSITE_CPU_DBG1_LAR);
216 }
217}
218
219void start_cpu(u32 reset_vector)
220{
221 /* Enable VDD_CPU */
222 enable_cpu_power_rail();
223
224 /* Hold the CPUs in reset */
225 reset_A9_cpu(1);
226
227 /* Disable the CPU clock */
228 enable_cpu_clock(0);
229
230 /* Enable CoreSight */
231 clock_enable_coresight(1);
232
233 /*
234 * Set the entry point for CPU execution from reset,
235 * if it's a non-zero value.
236 */
237 if (reset_vector)
238 writel(reset_vector, EXCEP_VECTOR_CPU_RESET_VECTOR);
239
240 /* Enable the CPU clock */
241 enable_cpu_clock(1);
242
243 /* If the CPU doesn't already have power, power it up */
244 powerup_cpu();
245
246 /* Take the CPU out of reset */
247 reset_A9_cpu(0);
248}
249
250
251void halt_avp(void)
252{
253 for (;;) {
254 writel((HALT_COP_EVENT_JTAG | HALT_COP_EVENT_IRQ_1 \
255 | HALT_COP_EVENT_FIQ_1 | (FLOW_MODE_STOP<<29)),
256 FLOW_CTLR_HALT_COP_EVENTS);
257 }
258}