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authorDaniel Baumann <daniel.baumann@progress-linux.org>2024-05-06 01:02:30 +0000
committerDaniel Baumann <daniel.baumann@progress-linux.org>2024-05-06 01:02:30 +0000
commit76cb841cb886eef6b3bee341a2266c76578724ad (patch)
treef5892e5ba6cc11949952a6ce4ecbe6d516d6ce58 /drivers/soc/tegra/fuse/fuse-tegra20.c
parentInitial commit. (diff)
downloadlinux-76cb841cb886eef6b3bee341a2266c76578724ad.tar.xz
linux-76cb841cb886eef6b3bee341a2266c76578724ad.zip
Adding upstream version 4.19.249.upstream/4.19.249
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'drivers/soc/tegra/fuse/fuse-tegra20.c')
-rw-r--r--drivers/soc/tegra/fuse/fuse-tegra20.c178
1 files changed, 178 insertions, 0 deletions
diff --git a/drivers/soc/tegra/fuse/fuse-tegra20.c b/drivers/soc/tegra/fuse/fuse-tegra20.c
new file mode 100644
index 000000000..49ff017f3
--- /dev/null
+++ b/drivers/soc/tegra/fuse/fuse-tegra20.c
@@ -0,0 +1,178 @@
+/*
+ * Copyright (c) 2013-2014, NVIDIA CORPORATION. All rights reserved.
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms and conditions of the GNU General Public License,
+ * version 2, as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
+ * more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program. If not, see <http://www.gnu.org/licenses/>.
+ *
+ * Based on drivers/misc/eeprom/sunxi_sid.c
+ */
+
+#include <linux/device.h>
+#include <linux/clk.h>
+#include <linux/completion.h>
+#include <linux/dmaengine.h>
+#include <linux/dma-mapping.h>
+#include <linux/err.h>
+#include <linux/io.h>
+#include <linux/kernel.h>
+#include <linux/kobject.h>
+#include <linux/of_device.h>
+#include <linux/platform_device.h>
+#include <linux/random.h>
+
+#include <soc/tegra/fuse.h>
+
+#include "fuse.h"
+
+#define FUSE_BEGIN 0x100
+#define FUSE_UID_LOW 0x08
+#define FUSE_UID_HIGH 0x0c
+
+static u32 tegra20_fuse_read_early(struct tegra_fuse *fuse, unsigned int offset)
+{
+ return readl_relaxed(fuse->base + FUSE_BEGIN + offset);
+}
+
+static void apb_dma_complete(void *args)
+{
+ struct tegra_fuse *fuse = args;
+
+ complete(&fuse->apbdma.wait);
+}
+
+static u32 tegra20_fuse_read(struct tegra_fuse *fuse, unsigned int offset)
+{
+ unsigned long flags = DMA_PREP_INTERRUPT | DMA_CTRL_ACK;
+ struct dma_async_tx_descriptor *dma_desc;
+ unsigned long time_left;
+ u32 value = 0;
+ int err;
+
+ mutex_lock(&fuse->apbdma.lock);
+
+ fuse->apbdma.config.src_addr = fuse->phys + FUSE_BEGIN + offset;
+
+ err = dmaengine_slave_config(fuse->apbdma.chan, &fuse->apbdma.config);
+ if (err)
+ goto out;
+
+ dma_desc = dmaengine_prep_slave_single(fuse->apbdma.chan,
+ fuse->apbdma.phys,
+ sizeof(u32), DMA_DEV_TO_MEM,
+ flags);
+ if (!dma_desc)
+ goto out;
+
+ dma_desc->callback = apb_dma_complete;
+ dma_desc->callback_param = fuse;
+
+ reinit_completion(&fuse->apbdma.wait);
+
+ clk_prepare_enable(fuse->clk);
+
+ dmaengine_submit(dma_desc);
+ dma_async_issue_pending(fuse->apbdma.chan);
+ time_left = wait_for_completion_timeout(&fuse->apbdma.wait,
+ msecs_to_jiffies(50));
+
+ if (WARN(time_left == 0, "apb read dma timed out"))
+ dmaengine_terminate_all(fuse->apbdma.chan);
+ else
+ value = *fuse->apbdma.virt;
+
+ clk_disable_unprepare(fuse->clk);
+
+out:
+ mutex_unlock(&fuse->apbdma.lock);
+ return value;
+}
+
+static bool dma_filter(struct dma_chan *chan, void *filter_param)
+{
+ struct device_node *np = chan->device->dev->of_node;
+
+ return of_device_is_compatible(np, "nvidia,tegra20-apbdma");
+}
+
+static int tegra20_fuse_probe(struct tegra_fuse *fuse)
+{
+ dma_cap_mask_t mask;
+
+ dma_cap_zero(mask);
+ dma_cap_set(DMA_SLAVE, mask);
+
+ fuse->apbdma.chan = __dma_request_channel(&mask, dma_filter, NULL);
+ if (!fuse->apbdma.chan)
+ return -EPROBE_DEFER;
+
+ fuse->apbdma.virt = dma_alloc_coherent(fuse->dev, sizeof(u32),
+ &fuse->apbdma.phys,
+ GFP_KERNEL);
+ if (!fuse->apbdma.virt) {
+ dma_release_channel(fuse->apbdma.chan);
+ return -ENOMEM;
+ }
+
+ fuse->apbdma.config.src_addr_width = DMA_SLAVE_BUSWIDTH_4_BYTES;
+ fuse->apbdma.config.dst_addr_width = DMA_SLAVE_BUSWIDTH_4_BYTES;
+ fuse->apbdma.config.src_maxburst = 1;
+ fuse->apbdma.config.dst_maxburst = 1;
+ fuse->apbdma.config.direction = DMA_DEV_TO_MEM;
+ fuse->apbdma.config.device_fc = false;
+
+ init_completion(&fuse->apbdma.wait);
+ mutex_init(&fuse->apbdma.lock);
+ fuse->read = tegra20_fuse_read;
+
+ return 0;
+}
+
+static const struct tegra_fuse_info tegra20_fuse_info = {
+ .read = tegra20_fuse_read,
+ .size = 0x1f8,
+ .spare = 0x100,
+};
+
+/* Early boot code. This code is called before the devices are created */
+
+static void __init tegra20_fuse_add_randomness(void)
+{
+ u32 randomness[7];
+
+ randomness[0] = tegra_sku_info.sku_id;
+ randomness[1] = tegra_read_straps();
+ randomness[2] = tegra_read_chipid();
+ randomness[3] = tegra_sku_info.cpu_process_id << 16;
+ randomness[3] |= tegra_sku_info.soc_process_id;
+ randomness[4] = tegra_sku_info.cpu_speedo_id << 16;
+ randomness[4] |= tegra_sku_info.soc_speedo_id;
+ randomness[5] = tegra_fuse_read_early(FUSE_UID_LOW);
+ randomness[6] = tegra_fuse_read_early(FUSE_UID_HIGH);
+
+ add_device_randomness(randomness, sizeof(randomness));
+}
+
+static void __init tegra20_fuse_init(struct tegra_fuse *fuse)
+{
+ fuse->read_early = tegra20_fuse_read_early;
+
+ tegra_init_revision();
+ fuse->soc->speedo_init(&tegra_sku_info);
+ tegra20_fuse_add_randomness();
+}
+
+const struct tegra_fuse_soc tegra20_fuse_soc = {
+ .init = tegra20_fuse_init,
+ .speedo_init = tegra20_init_speedo_data,
+ .probe = tegra20_fuse_probe,
+ .info = &tegra20_fuse_info,
+};