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Tom Rini10e47792018-05-06 17:58:06 -04001// SPDX-License-Identifier: GPL-2.0+
Tom Warren41b68382011-01-27 10:58:05 +00002/*
3 * (C) Copyright 2010,2011
4 * NVIDIA Corporation <www.nvidia.com>
Tom Warren41b68382011-01-27 10:58:05 +00005 */
6
7#include <common.h>
Simon Glass74472ac2014-11-10 17:16:51 -07008#include <dm.h>
Simon Glass5e6201b2019-08-01 09:46:51 -06009#include <env.h>
Simon Glass0655c912015-04-14 21:03:28 -060010#include <errno.h>
Simon Glass6980b6b2019-11-14 12:57:45 -070011#include <init.h>
Simon Glass0f2af882020-05-10 11:40:05 -060012#include <log.h>
Tom Warren41b68382011-01-27 10:58:05 +000013#include <ns16550.h>
Simon Glass15023922017-06-12 06:21:39 -060014#include <usb.h>
Tom Warren41b68382011-01-27 10:58:05 +000015#include <asm/io.h>
Stephen Warren8d1fb312015-01-19 16:25:52 -070016#include <asm/arch-tegra/ap.h>
Tom Warrenab371962012-09-19 15:50:56 -070017#include <asm/arch-tegra/board.h>
Thierry Reding7cef2b22019-04-15 11:32:28 +020018#include <asm/arch-tegra/cboot.h>
Tom Warrenab371962012-09-19 15:50:56 -070019#include <asm/arch-tegra/clk_rst.h>
20#include <asm/arch-tegra/pmc.h>
Thierry Redingcf390082019-04-15 11:32:17 +020021#include <asm/arch-tegra/pmu.h>
Tom Warrenab371962012-09-19 15:50:56 -070022#include <asm/arch-tegra/sys_proto.h>
23#include <asm/arch-tegra/uart.h>
24#include <asm/arch-tegra/warmboot.h>
Alexandre Courbot7f936d42015-07-09 16:33:00 +090025#include <asm/arch-tegra/gpu.h>
Simon Glass15023922017-06-12 06:21:39 -060026#include <asm/arch-tegra/usb.h>
27#include <asm/arch-tegra/xusb-padctl.h>
Thierry Reding45ad0b02019-04-15 11:32:18 +020028#if IS_ENABLED(CONFIG_TEGRA_CLKRST)
Simon Glass15023922017-06-12 06:21:39 -060029#include <asm/arch/clock.h>
Thierry Reding45ad0b02019-04-15 11:32:18 +020030#endif
Thierry Reding7c0b1502019-04-15 11:32:21 +020031#if IS_ENABLED(CONFIG_TEGRA_PINCTRL)
Simon Glass15023922017-06-12 06:21:39 -060032#include <asm/arch/funcmux.h>
33#include <asm/arch/pinmux.h>
Thierry Reding7c0b1502019-04-15 11:32:21 +020034#endif
Simon Glass15023922017-06-12 06:21:39 -060035#include <asm/arch/tegra.h>
Tom Warrend32b2a42012-12-11 13:34:17 +000036#ifdef CONFIG_TEGRA_CLOCK_SCALING
37#include <asm/arch/emc.h>
38#endif
Jimmy Zhanga308d462012-04-10 05:17:06 +000039#include "emc.h"
Tom Warren41b68382011-01-27 10:58:05 +000040
41DECLARE_GLOBAL_DATA_PTR;
42
Simon Glass74472ac2014-11-10 17:16:51 -070043#ifdef CONFIG_SPL_BUILD
44/* TODO(sjg@chromium.org): Remove once SPL supports device tree */
45U_BOOT_DEVICE(tegra_gpios) = {
46 "gpio_tegra"
47};
48#endif
49
Jeroen Hofstee93dfae72014-10-08 22:57:46 +020050__weak void pinmux_init(void) {}
51__weak void pin_mux_usb(void) {}
52__weak void pin_mux_spi(void) {}
Stephen Warrenc044fe22016-09-13 10:45:47 -060053__weak void pin_mux_mmc(void) {}
Jeroen Hofstee93dfae72014-10-08 22:57:46 +020054__weak void gpio_early_init_uart(void) {}
55__weak void pin_mux_display(void) {}
Tom Warrenf3035ca2015-02-20 12:22:22 -070056__weak void start_cpu_fan(void) {}
Thierry Reding7cef2b22019-04-15 11:32:28 +020057__weak void cboot_late_init(void) {}
Lucas Stach18561f72012-09-25 20:21:14 +000058
Tom Warren6b33c832014-01-24 12:46:11 -070059#if defined(CONFIG_TEGRA_NAND)
Jeroen Hofstee93dfae72014-10-08 22:57:46 +020060__weak void pin_mux_nand(void)
Lucas Stach04585842012-09-29 10:02:09 +000061{
62 funcmux_select(PERIPH_ID_NDFLASH, FUNCMUX_DEFAULT);
63}
Tom Warren6b33c832014-01-24 12:46:11 -070064#endif
Lucas Stach04585842012-09-29 10:02:09 +000065
Tom Warren41b68382011-01-27 10:58:05 +000066/*
Wei Ni39d45ed2012-04-02 13:18:58 +000067 * Routine: power_det_init
68 * Description: turn off power detects
69 */
70static void power_det_init(void)
71{
Allen Martin55d98a12012-08-31 08:30:00 +000072#if defined(CONFIG_TEGRA20)
Tom Warren22562a42012-09-04 17:00:24 -070073 struct pmc_ctlr *const pmc = (struct pmc_ctlr *)NV_PA_PMC_BASE;
Wei Ni39d45ed2012-04-02 13:18:58 +000074
75 /* turn off power detects */
76 writel(0, &pmc->pmc_pwr_det_latch);
77 writel(0, &pmc->pmc_pwr_det);
78#endif
79}
Simon Glass675804d2015-04-14 21:03:24 -060080
Simon Glass69c93c72015-04-14 21:03:25 -060081__weak int tegra_board_id(void)
82{
83 return -1;
84}
85
Simon Glass675804d2015-04-14 21:03:24 -060086#ifdef CONFIG_DISPLAY_BOARDINFO
87int checkboard(void)
88{
Simon Glass69c93c72015-04-14 21:03:25 -060089 int board_id = tegra_board_id();
90
91 printf("Board: %s", CONFIG_TEGRA_BOARD_STRING);
92 if (board_id != -1)
93 printf(", ID: %d\n", board_id);
94 printf("\n");
Simon Glass675804d2015-04-14 21:03:24 -060095
96 return 0;
97}
98#endif /* CONFIG_DISPLAY_BOARDINFO */
Wei Ni39d45ed2012-04-02 13:18:58 +000099
Simon Glass0cf62dd2015-04-14 21:03:27 -0600100__weak int tegra_lcd_pmic_init(int board_it)
101{
102 return 0;
103}
104
Simon Glass44a68082015-06-05 14:39:42 -0600105__weak int nvidia_board_init(void)
106{
107 return 0;
108}
109
Wei Ni39d45ed2012-04-02 13:18:58 +0000110/*
Tom Warren41b68382011-01-27 10:58:05 +0000111 * Routine: board_init
112 * Description: Early hardware init.
113 */
114int board_init(void)
115{
Jimmy Zhanga308d462012-04-10 05:17:06 +0000116 __maybe_unused int err;
Simon Glass0cf62dd2015-04-14 21:03:27 -0600117 __maybe_unused int board_id;
Jimmy Zhanga308d462012-04-10 05:17:06 +0000118
Simon Glass704e60d2011-11-05 04:46:51 +0000119 /* Do clocks and UART first so that printf() works */
Thierry Reding45ad0b02019-04-15 11:32:18 +0200120#if IS_ENABLED(CONFIG_TEGRA_CLKRST)
Simon Glassc2ea5e42011-09-21 12:40:04 +0000121 clock_init();
122 clock_verify();
Thierry Reding45ad0b02019-04-15 11:32:18 +0200123#endif
Simon Glassc2ea5e42011-09-21 12:40:04 +0000124
Alexandre Courbotf36729d2015-10-19 13:57:03 +0900125 tegra_gpu_config();
Alexandre Courbot7f936d42015-07-09 16:33:00 +0900126
Simon Glass1121b1b2014-10-13 23:42:13 -0600127#ifdef CONFIG_TEGRA_SPI
Stephen Warrend2f67fe2012-06-12 08:33:40 +0000128 pin_mux_spi();
Tom Warrenee554f82011-11-05 09:48:11 +0000129#endif
Allen Martinba4fb9b2013-01-29 13:51:28 +0000130
Masahiro Yamadab2c88682017-01-10 13:32:07 +0900131#ifdef CONFIG_MMC_SDHCI_TEGRA
Stephen Warrenc044fe22016-09-13 10:45:47 -0600132 pin_mux_mmc();
133#endif
134
Simon Glasseb210832016-01-30 16:37:48 -0700135 /* Init is handled automatically in the driver-model case */
Simon Glassd5f36132016-01-30 16:38:02 -0700136#if defined(CONFIG_DM_VIDEO)
Marc Dietrich9bbe64b2012-11-25 11:26:11 +0000137 pin_mux_display();
Simon Glass3e2b2d92016-01-30 16:37:49 -0700138#endif
Tom Warren41b68382011-01-27 10:58:05 +0000139 /* boot param addr */
140 gd->bd->bi_boot_params = (NV_PA_SDRAM_BASE + 0x100);
Wei Ni39d45ed2012-04-02 13:18:58 +0000141
142 power_det_init();
143
Simon Glass026fefb2012-10-30 07:28:53 +0000144#ifdef CONFIG_SYS_I2C_TEGRA
Simon Glasse772be82012-04-02 13:18:54 +0000145# ifdef CONFIG_TEGRA_PMU
146 if (pmu_set_nominal())
147 debug("Failed to select nominal voltages\n");
Jimmy Zhanga308d462012-04-10 05:17:06 +0000148# ifdef CONFIG_TEGRA_CLOCK_SCALING
149 err = board_emc_init();
150 if (err)
151 debug("Memory controller init failed: %d\n", err);
152# endif
153# endif /* CONFIG_TEGRA_PMU */
Simon Glass026fefb2012-10-30 07:28:53 +0000154#endif /* CONFIG_SYS_I2C_TEGRA */
Tom Warren41b68382011-01-27 10:58:05 +0000155
Simon Glass5d73a8d2012-02-27 10:52:50 +0000156#ifdef CONFIG_USB_EHCI_TEGRA
157 pin_mux_usb();
Simon Glass5d73a8d2012-02-27 10:52:50 +0000158#endif
Mateusz Zalegad862f892013-10-04 19:22:26 +0200159
Simon Glassd5f36132016-01-30 16:38:02 -0700160#if defined(CONFIG_DM_VIDEO)
Simon Glass0cf62dd2015-04-14 21:03:27 -0600161 board_id = tegra_board_id();
162 err = tegra_lcd_pmic_init(board_id);
Simon Glass9d8271e2017-06-12 06:21:59 -0600163 if (err) {
164 debug("Failed to set up LCD PMIC\n");
Simon Glass0cf62dd2015-04-14 21:03:27 -0600165 return err;
Simon Glass9d8271e2017-06-12 06:21:59 -0600166 }
Simon Glass3e2b2d92016-01-30 16:37:49 -0700167#endif
Simon Glass5d73a8d2012-02-27 10:52:50 +0000168
Lucas Stach04585842012-09-29 10:02:09 +0000169#ifdef CONFIG_TEGRA_NAND
170 pin_mux_nand();
171#endif
172
Simon Glasscf0c6e22017-07-25 08:29:59 -0600173 tegra_xusb_padctl_init();
Thierry Redingf202e022014-12-09 22:25:09 -0700174
Tom Warren22562a42012-09-04 17:00:24 -0700175#ifdef CONFIG_TEGRA_LP0
Allen Martin0ca1a452012-08-31 08:30:11 +0000176 /* save Sdram params to PMC 2, 4, and 24 for WB0 */
177 warmboot_save_sdram_params();
178
Simon Glass8cc8f612012-04-02 13:18:57 +0000179 /* prepare the WB code to LP0 location */
180 warmboot_prepare_code(TEGRA_LP0_ADDR, TEGRA_LP0_SIZE);
181#endif
Simon Glass44a68082015-06-05 14:39:42 -0600182 return nvidia_board_init();
Tom Warren41b68382011-01-27 10:58:05 +0000183}
Simon Glassdfcee792011-09-21 12:40:03 +0000184
JC Kuof479aca2020-03-26 16:10:09 -0700185void board_cleanup_before_linux(void)
186{
187 /* power down UPHY PLL */
188 tegra_xusb_padctl_exit();
189}
190
Simon Glassdfcee792011-09-21 12:40:03 +0000191#ifdef CONFIG_BOARD_EARLY_INIT_F
Thierry Reding2fa4db02012-06-04 20:02:27 +0000192static void __gpio_early_init(void)
193{
194}
195
196void gpio_early_init(void) __attribute__((weak, alias("__gpio_early_init")));
197
Simon Glassdfcee792011-09-21 12:40:03 +0000198int board_early_init_f(void)
199{
Thierry Reding45ad0b02019-04-15 11:32:18 +0200200#if IS_ENABLED(CONFIG_TEGRA_CLKRST)
Simon Glass2b4029a2017-05-31 17:57:16 -0600201 if (!clock_early_init_done())
202 clock_early_init();
Thierry Reding45ad0b02019-04-15 11:32:18 +0200203#endif
Simon Glass2b4029a2017-05-31 17:57:16 -0600204
Stephen Warren5a44ab42016-01-26 10:59:42 -0700205#if defined(CONFIG_TEGRA_DISCONNECT_UDC_ON_BOOT)
206#define USBCMD_FS2 (1 << 15)
207 {
208 struct usb_ctlr *usbctlr = (struct usb_ctlr *)0x7d000000;
209 writel(USBCMD_FS2, &usbctlr->usb_cmd);
210 }
211#endif
212
Thierry Redingff81d752015-07-28 11:35:53 +0200213 /* Do any special system timer/TSC setup */
Thierry Reding45ad0b02019-04-15 11:32:18 +0200214#if IS_ENABLED(CONFIG_TEGRA_CLKRST)
215# if defined(CONFIG_TEGRA_SUPPORT_NON_SECURE)
Thierry Redingff81d752015-07-28 11:35:53 +0200216 if (!tegra_cpu_is_non_secure())
Thierry Reding45ad0b02019-04-15 11:32:18 +0200217# endif
Thierry Redingff81d752015-07-28 11:35:53 +0200218 arch_timer_init();
Thierry Reding45ad0b02019-04-15 11:32:18 +0200219#endif
Thierry Redingff81d752015-07-28 11:35:53 +0200220
Tom Warren872111a2020-02-28 16:17:07 -0700221#if defined(CONFIG_DISABLE_SDMMC1_EARLY)
222 /*
223 * Turn off (reset/disable) SDMMC1 on Nano here, before GPIO INIT.
224 * We do this because earlier bootloaders have enabled power to
225 * SDMMC1 on Nano, and toggling power-gpio (PZ3) in pinmux_init()
226 * results in power being back-driven into the SD-card and SDMMC1
227 * HW, which is 'bad' as per the HW team.
228 *
229 * From the HW team: "LDO2 from the PMIC has already been set to 3.3v in
230 * nvtboot/CBoot on Nano (for SD-card boot). So when U-Boot's GPIO_INIT
231 * table sets PZ3 to OUT0 as per the pinmux spreadsheet, it turns off
232 * the loadswitch. When PZ3 is 0 and not driving, essentially the SDCard
233 * voltage turns off. Since the SDCard voltage is no longer there, the
234 * SDMMC CLK/DAT lines are backdriving into what essentially is a
235 * powered-off SDCard, that's why the voltage drops from 3.3V to ~1.6V"
236 *
237 * Note that this can probably be removed when we change over to storing
238 * all BL components on QSPI on Nano, and U-Boot then becomes the first
239 * one to turn on SDMMC1 power. Another fix would be to have CBoot
240 * disable power/gate SDMMC1 off before handing off to U-Boot/kernel.
241 */
242 reset_set_enable(PERIPH_ID_SDMMC1, 1);
243 clock_set_enable(PERIPH_ID_SDMMC1, 0);
244#endif /* CONFIG_DISABLE_SDMMC1_EARLY */
245
Tom Warrend32b2a42012-12-11 13:34:17 +0000246 pinmux_init();
Simon Glassa8ccc8b2011-11-28 15:04:40 +0000247 board_init_uart_f();
Simon Glassdfcee792011-09-21 12:40:03 +0000248
249 /* Initialize periph GPIOs */
Thierry Reding2fa4db02012-06-04 20:02:27 +0000250 gpio_early_init();
Simon Glass704e60d2011-11-05 04:46:51 +0000251 gpio_early_init_uart();
Lucas Stach18561f72012-09-25 20:21:14 +0000252
Simon Glassdfcee792011-09-21 12:40:03 +0000253 return 0;
254}
255#endif /* EARLY_INIT */
Simon Glass4f476f32012-10-17 13:24:52 +0000256
257int board_late_init(void)
258{
Stephen Warren8d1fb312015-01-19 16:25:52 -0700259#if defined(CONFIG_TEGRA_SUPPORT_NON_SECURE)
260 if (tegra_cpu_is_non_secure()) {
261 printf("CPU is in NS mode\n");
Simon Glass6a38e412017-08-03 12:22:09 -0600262 env_set("cpu_ns_mode", "1");
Stephen Warren8d1fb312015-01-19 16:25:52 -0700263 } else {
Simon Glass6a38e412017-08-03 12:22:09 -0600264 env_set("cpu_ns_mode", "");
Stephen Warren8d1fb312015-01-19 16:25:52 -0700265 }
266#endif
Tom Warrenf3035ca2015-02-20 12:22:22 -0700267 start_cpu_fan();
Thierry Reding7cef2b22019-04-15 11:32:28 +0200268 cboot_late_init();
Tom Warrenf3035ca2015-02-20 12:22:22 -0700269
Simon Glass4f476f32012-10-17 13:24:52 +0000270 return 0;
271}
Thierry Reding6d835fa2015-07-27 11:45:24 -0600272
Stephen Warren3ffd0902015-08-07 16:12:45 -0600273/*
274 * In some SW environments, a memory carve-out exists to house a secure
275 * monitor, a trusted OS, and/or various statically allocated media buffers.
276 *
277 * This carveout exists at the highest possible address that is within a
278 * 32-bit physical address space.
279 *
280 * This function returns the total size of this carve-out. At present, the
281 * returned value is hard-coded for simplicity. In the future, it may be
282 * possible to determine the carve-out size:
283 * - By querying some run-time information source, such as:
284 * - A structure passed to U-Boot by earlier boot software.
285 * - SoC registers.
286 * - A call into the secure monitor.
287 * - In the per-board U-Boot configuration header, based on knowledge of the
288 * SW environment that U-Boot is being built for.
289 *
290 * For now, we support two configurations in U-Boot:
291 * - 32-bit ports without any form of carve-out.
292 * - 64 bit ports which are assumed to use a carve-out of a conservatively
293 * hard-coded size.
294 */
295static ulong carveout_size(void)
296{
Thierry Reding6d835fa2015-07-27 11:45:24 -0600297#ifdef CONFIG_ARM64
Stephen Warren3ffd0902015-08-07 16:12:45 -0600298 return SZ_512M;
Stephen Warrenc12800f2018-06-22 13:03:19 -0600299#elif defined(CONFIG_ARMV7_SECURE_RESERVE_SIZE)
300 // BASE+SIZE might not == 4GB. If so, we want the carveout to cover
301 // from BASE to 4GB, not BASE to BASE+SIZE.
Stephen Warrena963a782018-07-31 12:38:27 -0600302 return (0 - CONFIG_ARMV7_SECURE_BASE) & ~(SZ_2M - 1);
Stephen Warren3ffd0902015-08-07 16:12:45 -0600303#else
304 return 0;
305#endif
306}
307
308/*
309 * Determine the amount of usable RAM below 4GiB, taking into account any
310 * carve-out that may be assigned.
311 */
312static ulong usable_ram_size_below_4g(void)
313{
314 ulong total_size_below_4g;
315 ulong usable_size_below_4g;
316
317 /*
318 * The total size of RAM below 4GiB is the lesser address of:
319 * (a) 2GiB itself (RAM starts at 2GiB, and 4GiB - 2GiB == 2GiB).
320 * (b) The size RAM physically present in the system.
321 */
322 if (gd->ram_size < SZ_2G)
323 total_size_below_4g = gd->ram_size;
324 else
325 total_size_below_4g = SZ_2G;
326
327 /* Calculate usable RAM by subtracting out any carve-out size */
328 usable_size_below_4g = total_size_below_4g - carveout_size();
329
330 return usable_size_below_4g;
331}
332
333/*
334 * Represent all available RAM in either one or two banks.
335 *
336 * The first bank describes any usable RAM below 4GiB.
337 * The second bank describes any RAM above 4GiB.
338 *
339 * This split is driven by the following requirements:
340 * - The NVIDIA L4T kernel requires separate entries in the DT /memory/reg
341 * property for memory below and above the 4GiB boundary. The layout of that
342 * DT property is directly driven by the entries in the U-Boot bank array.
343 * - The potential existence of a carve-out at the end of RAM below 4GiB can
344 * only be represented using multiple banks.
345 *
346 * Explicitly removing the carve-out RAM from the bank entries makes the RAM
347 * layout a bit more obvious, e.g. when running "bdinfo" at the U-Boot
348 * command-line.
349 *
350 * This does mean that the DT U-Boot passes to the Linux kernel will not
351 * include this RAM in /memory/reg at all. An alternative would be to include
352 * all RAM in the U-Boot banks (and hence DT), and add a /memreserve/ node
353 * into DT to stop the kernel from using the RAM. IIUC, I don't /think/ the
354 * Linux kernel will ever need to access any RAM in* the carve-out via a CPU
355 * mapping, so either way is acceptable.
356 *
357 * On 32-bit systems, we never define a bank for RAM above 4GiB, since the
358 * start address of that bank cannot be represented in the 32-bit .size
359 * field.
360 */
Simon Glass2f949c32017-03-31 08:40:32 -0600361int dram_init_banksize(void)
Stephen Warren3ffd0902015-08-07 16:12:45 -0600362{
Thierry Reding7cef2b22019-04-15 11:32:28 +0200363 int err;
364
365 /* try to compute DRAM bank size based on cboot DTB first */
366 err = cboot_dram_init_banksize();
367 if (err == 0)
368 return err;
369
370 /* fall back to default DRAM bank size computation */
371
Stephen Warren3ffd0902015-08-07 16:12:45 -0600372 gd->bd->bi_dram[0].start = CONFIG_SYS_SDRAM_BASE;
373 gd->bd->bi_dram[0].size = usable_ram_size_below_4g();
374
Simon Glass46fcfc12015-11-19 20:27:02 -0700375#ifdef CONFIG_PCI
376 gd->pci_ram_top = gd->bd->bi_dram[0].start + gd->bd->bi_dram[0].size;
377#endif
378
Stephen Warren3ffd0902015-08-07 16:12:45 -0600379#ifdef CONFIG_PHYS_64BIT
380 if (gd->ram_size > SZ_2G) {
381 gd->bd->bi_dram[1].start = 0x100000000;
382 gd->bd->bi_dram[1].size = gd->ram_size - SZ_2G;
383 } else
384#endif
385 {
386 gd->bd->bi_dram[1].start = 0;
387 gd->bd->bi_dram[1].size = 0;
388 }
Simon Glass2f949c32017-03-31 08:40:32 -0600389
390 return 0;
Stephen Warren3ffd0902015-08-07 16:12:45 -0600391}
392
Thierry Reding6d835fa2015-07-27 11:45:24 -0600393/*
394 * Most hardware on 64-bit Tegra is still restricted to DMA to the lower
395 * 32-bits of the physical address space. Cap the maximum usable RAM area
396 * at 4 GiB to avoid DMA buffers from being allocated beyond the 32-bit
Stephen Warren3ffd0902015-08-07 16:12:45 -0600397 * boundary that most devices can address. Also, don't let U-Boot use any
398 * carve-out, as mentioned above.
Stephen Warren30d19662015-07-29 13:47:58 -0600399 *
Stephen Warren3ffd0902015-08-07 16:12:45 -0600400 * This function is called before dram_init_banksize(), so we can't simply
401 * return gd->bd->bi_dram[1].start + gd->bd->bi_dram[1].size.
Thierry Reding6d835fa2015-07-27 11:45:24 -0600402 */
403ulong board_get_usable_ram_top(ulong total_size)
404{
Thierry Reding7cef2b22019-04-15 11:32:28 +0200405 ulong ram_top;
406
407 /* try to get top of usable RAM based on cboot DTB first */
408 ram_top = cboot_get_usable_ram_top(total_size);
409 if (ram_top > 0)
410 return ram_top;
411
412 /* fall back to default usable RAM computation */
413
Stephen Warren3ffd0902015-08-07 16:12:45 -0600414 return CONFIG_SYS_SDRAM_BASE + usable_ram_size_below_4g();
Thierry Reding6d835fa2015-07-27 11:45:24 -0600415}