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Release 4.11 arch/arm/mach-mvebu/mvebu-soc-id.c

/*
 * ID and revision information for mvebu SoCs
 *
 * Copyright (C) 2014 Marvell
 *
 * Gregory CLEMENT <gregory.clement@free-electrons.com>
 *
 * This file is licensed under the terms of the GNU General Public
 * License version 2.  This program is licensed "as is" without any
 * warranty of any kind, whether express or implied.
 *
 * All the mvebu SoCs have information related to their variant and
 * revision that can be read from the PCI control register. This is
 * done before the PCI initialization to avoid any conflict. Once the
 * ID and revision are retrieved, the mapping is freed.
 */


#define pr_fmt(fmt) "mvebu-soc-id: " fmt

#include <linux/clk.h>
#include <linux/init.h>
#include <linux/io.h>
#include <linux/kernel.h>
#include <linux/of.h>
#include <linux/of_address.h>
#include <linux/slab.h>
#include <linux/sys_soc.h>
#include "common.h"
#include "mvebu-soc-id.h"


#define PCIE_DEV_ID_OFF		0x0

#define PCIE_DEV_REV_OFF	0x8


#define SOC_ID_MASK	    0xFFFF0000

#define SOC_REV_MASK	    0xFF


static u32 soc_dev_id;

static u32 soc_rev;

static bool is_id_valid;


static const struct of_device_id mvebu_pcie_of_match_table[] = {
	{ .compatible = "marvell,armada-xp-pcie", },
	{ .compatible = "marvell,armada-370-pcie", },
	{ .compatible = "marvell,kirkwood-pcie" },
	{},
};


int mvebu_get_soc_id(u32 *dev, u32 *rev) { if (is_id_valid) { *dev = soc_dev_id; *rev = soc_rev; return 0; } else return -ENODEV; }

Contributors

PersonTokensPropCommitsCommitProp
Gregory CLEMENT37100.00%2100.00%
Total37100.00%2100.00%


static int __init get_soc_id_by_pci(void) { struct device_node *np; int ret = 0; void __iomem *pci_base; struct clk *clk; struct device_node *child; np = of_find_matching_node(NULL, mvebu_pcie_of_match_table); if (!np) return ret; /* * ID and revision are available from any port, so we * just pick the first one */ child = of_get_next_child(np, NULL); if (child == NULL) { pr_err("cannot get pci node\n"); ret = -ENOMEM; goto clk_err; } clk = of_clk_get_by_name(child, NULL); if (IS_ERR(clk)) { pr_err("cannot get clock\n"); ret = -ENOMEM; goto clk_err; } ret = clk_prepare_enable(clk); if (ret) { pr_err("cannot enable clock\n"); goto clk_err; } pci_base = of_iomap(child, 0); if (pci_base == NULL) { pr_err("cannot map registers\n"); ret = -ENOMEM; goto res_ioremap; } /* SoC ID */ soc_dev_id = readl(pci_base + PCIE_DEV_ID_OFF) >> 16; /* SoC revision */ soc_rev = readl(pci_base + PCIE_DEV_REV_OFF) & SOC_REV_MASK; is_id_valid = true; pr_info("MVEBU SoC ID=0x%X, Rev=0x%X\n", soc_dev_id, soc_rev); iounmap(pci_base); res_ioremap: /* * If the PCIe unit is actually enabled and we have PCI * support in the kernel, we intentionally do not release the * reference to the clock. We want to keep it running since * the bootloader does some PCIe link configuration that the * kernel is for now unable to do, and gating the clock would * make us loose this precious configuration. */ if (!of_device_is_available(child) || !IS_ENABLED(CONFIG_PCI_MVEBU)) { clk_disable_unprepare(clk); clk_put(clk); } clk_err: of_node_put(child); of_node_put(np); return ret; }

Contributors

PersonTokensPropCommitsCommitProp
Gregory CLEMENT22891.20%360.00%
Thomas Petazzoni228.80%240.00%
Total250100.00%5100.00%


static int __init mvebu_soc_id_init(void) { /* * First try to get the ID and the revision by the system * register and use PCI registers only if it is not possible */ if (!mvebu_system_controller_get_soc_id(&soc_dev_id, &soc_rev)) { is_id_valid = true; pr_info("MVEBU SoC ID=0x%X, Rev=0x%X\n", soc_dev_id, soc_rev); return 0; } return get_soc_id_by_pci(); }

Contributors

PersonTokensPropCommitsCommitProp
Gregory CLEMENT44100.00%1100.00%
Total44100.00%1100.00%

early_initcall(mvebu_soc_id_init);
static int __init mvebu_soc_device(void) { struct soc_device_attribute *soc_dev_attr; struct soc_device *soc_dev; /* Also protects against running on non-mvebu systems */ if (!is_id_valid) return 0; soc_dev_attr = kzalloc(sizeof(*soc_dev_attr), GFP_KERNEL); if (!soc_dev_attr) return -ENOMEM; soc_dev_attr->family = kasprintf(GFP_KERNEL, "Marvell"); soc_dev_attr->revision = kasprintf(GFP_KERNEL, "%X", soc_rev); soc_dev_attr->soc_id = kasprintf(GFP_KERNEL, "%X", soc_dev_id); soc_dev = soc_device_register(soc_dev_attr); if (IS_ERR(soc_dev)) { kfree(soc_dev_attr->family); kfree(soc_dev_attr->revision); kfree(soc_dev_attr->soc_id); kfree(soc_dev_attr); } return 0; }

Contributors

PersonTokensPropCommitsCommitProp
Andrew Lunn132100.00%1100.00%
Total132100.00%1100.00%

postcore_initcall(mvebu_soc_device);

Overall Contributors

PersonTokensPropCommitsCommitProp
Gregory CLEMENT39869.70%444.44%
Andrew Lunn15026.27%222.22%
Thomas Petazzoni234.03%333.33%
Total571100.00%9100.00%
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