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-rw-r--r--src/soc/cavium/cn81xx/sdram.c46
1 files changed, 46 insertions, 0 deletions
diff --git a/src/soc/cavium/cn81xx/sdram.c b/src/soc/cavium/cn81xx/sdram.c
index 2342b049ef..05546cc9b1 100644
--- a/src/soc/cavium/cn81xx/sdram.c
+++ b/src/soc/cavium/cn81xx/sdram.c
@@ -3,6 +3,7 @@
*
* Copyright 2018 Facebook, Inc.
* Copyright 2003-2017 Cavium Inc. <support@cavium.com>
+ * Copyright 2019 9elements Agency GmbH
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
@@ -28,17 +29,61 @@
#include <libbdk-hal/bdk-utils.h>
#include <libbdk-hal/bdk-l2c.h>
#include <libdram/libdram-config.h>
+#include <soc/ecam.h>
+#include <device/pci_ops.h>
+#include <device/pci.h>
size_t sdram_size_mb(void)
{
return bdk_dram_get_size_mbytes(0);
}
+#define BDK_RNM_CTL_STATUS 0
+#define BDK_RNM_RANDOM 0x100000
+
+#if ENV_ROMSTAGE
+/* Enable RNG for DRAM init */
+static void rnm_init(void)
+{
+ /* Bus numbers are hardcoded in ASIC. No need to program bridges. */
+ pci_devfn_t dev = PCI_DEV(2, 0, 0);
+
+ u64 *bar = (u64 *)ecam0_get_bar_val(dev, 0);
+ if (!bar) {
+ printk(BIOS_ERR, "RNG: Failed to get BAR0\n");
+ return;
+ }
+
+ printk(BIOS_DEBUG, "RNG: BAR0 at %p\n", bar);
+
+ u64 reg = read64(&bar[BDK_RNM_CTL_STATUS]);
+ /*
+ * Enables the output of the RNG.
+ * Entropy enable for random number generator.
+ */
+ reg |= 3;
+ write64(&bar[BDK_RNM_CTL_STATUS], reg);
+
+ /* Read back after enable so we know it is done. */
+ reg = read64(&bar[BDK_RNM_CTL_STATUS]);
+ /*
+ * Errata (RNM-22528) First consecutive reads to RNM_RANDOM return same
+ * value. Before using the random entropy, read RNM_RANDOM at least once
+ * and discard the data
+ */
+ reg = read64(&bar[BDK_RNM_RANDOM]);
+ printk(BIOS_SPEW, "RNG: RANDOM %llx\n", reg);
+ reg = read64(&bar[BDK_RNM_RANDOM]);
+ printk(BIOS_SPEW, "RNG: RANDOM %llx\n", reg);
+}
+
/* based on bdk_boot_dram() */
void sdram_init(void)
{
printk(BIOS_DEBUG, "Initializing DRAM\n");
+ rnm_init();
+
/**
* FIXME: second arg is actually a desired frequency if set (the
* function usually obtains frequency via the config). That might
@@ -100,3 +145,4 @@ void sdram_init(void)
printk(BIOS_INFO, "SDRAM initialization finished.\n");
}
+#endif