remarkable-linux/arch/arm/mach-bcm/bcm_kona_smc.c
Alex Elder c64756cca2 ARM: bcm: clean up SMC code
This patch just does some simple cleanup in "bcm_kona_smc.c":
    - Get rid of the secure_bridge_data structure.  Instead, just
      define two globals that record the physical and virtual
      addresses of the SMC arguments buffer.  Use "buffer" instead
      of "bounce" in their names.  Drop of the erroneous __iomem
      annotation for the physical address.
    - Get rid of the initialized flag and just use a non-null buffer
      address to indicate that.
    - Get the size of the memory region when fetching the SMC
      arguments buffer location from the device tree.  Use it to
      call ioremap() directly rather than requiring of_iomap() to
      go look it up again.
    - Do some additional validation on that memory region size.
    - Flush caches unconditionally in __bcm_kona_smc(); nothing
      supplies SSAPI_BRCM_START_VC_CORE as a service id.
    - Drop a needless initialization of "rc" in __bcm_kona_smc().

It also deletes most of the content of "bcm_kona_smc.h" because it's
never actually used and is of questionable value anyway.

Signed-off-by: Alex Elder <elder@linaro.org>
Reviewed-by: Tim Kryger <tim.kryger@linaro.org>
Reviewed-by: Markus Mayer <markus.mayer@linaro.org>
Reviewed-by: Matt Porter <mporter@linaro.org>
Signed-off-by: Matt Porter <mporter@linaro.org>
2014-04-25 08:51:32 -04:00

128 lines
3.1 KiB
C

/*
* Copyright (C) 2013 Broadcom Corporation
*
* 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 the Free Software Foundation version 2.
*
* This program is distributed "as is" WITHOUT ANY WARRANTY of any
* kind, whether express or implied; without even the implied warranty
* of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*/
#include <stdarg.h>
#include <linux/smp.h>
#include <linux/io.h>
#include <linux/ioport.h>
#include <asm/cacheflush.h>
#include <linux/of_address.h>
#include "bcm_kona_smc.h"
static u32 bcm_smc_buffer_phys; /* physical address */
static void __iomem *bcm_smc_buffer; /* virtual address */
struct bcm_kona_smc_data {
unsigned service_id;
unsigned arg0;
unsigned arg1;
unsigned arg2;
unsigned arg3;
};
static const struct of_device_id bcm_kona_smc_ids[] __initconst = {
{.compatible = "brcm,kona-smc"},
{.compatible = "bcm,kona-smc"}, /* deprecated name */
{},
};
/* Map in the args buffer area */
int __init bcm_kona_smc_init(void)
{
struct device_node *node;
const __be32 *prop_val;
u64 prop_size = 0;
unsigned long buffer_size;
u32 buffer_phys;
/* Read buffer addr and size from the device tree node */
node = of_find_matching_node(NULL, bcm_kona_smc_ids);
if (!node)
return -ENODEV;
prop_val = of_get_address(node, 0, &prop_size, NULL);
if (!prop_val)
return -EINVAL;
/* We assume space for four 32-bit arguments */
if (prop_size < 4 * sizeof(u32) || prop_size > (u64)ULONG_MAX)
return -EINVAL;
buffer_size = (unsigned long)prop_size;
buffer_phys = be32_to_cpup(prop_val);
if (!buffer_phys)
return -EINVAL;
bcm_smc_buffer = ioremap(buffer_phys, buffer_size);
if (!bcm_smc_buffer)
return -ENOMEM;
bcm_smc_buffer_phys = buffer_phys;
pr_info("Kona Secure API initialized\n");
return 0;
}
/* __bcm_kona_smc() should only run on CPU 0, with pre-emption disabled */
static void __bcm_kona_smc(void *info)
{
struct bcm_kona_smc_data *data = info;
u32 *args = bcm_smc_buffer;
int rc;
BUG_ON(smp_processor_id() != 0);
BUG_ON(!args);
/* Copy the four 32 bit argument values into the bounce area */
writel_relaxed(data->arg0, args++);
writel_relaxed(data->arg1, args++);
writel_relaxed(data->arg2, args++);
writel(data->arg3, args);
/* Flush caches for input data passed to Secure Monitor */
flush_cache_all();
/* Trap into Secure Monitor */
rc = bcm_kona_smc_asm(data->service_id, bcm_smc_buffer_phys);
if (rc != SEC_ROM_RET_OK)
pr_err("Secure Monitor call failed (0x%x)!\n", rc);
}
unsigned bcm_kona_smc(unsigned service_id, unsigned arg0, unsigned arg1,
unsigned arg2, unsigned arg3)
{
struct bcm_kona_smc_data data;
data.service_id = service_id;
data.arg0 = arg0;
data.arg1 = arg1;
data.arg2 = arg2;
data.arg3 = arg3;
/*
* Due to a limitation of the secure monitor, we must use the SMP
* infrastructure to forward all secure monitor calls to Core 0.
*/
if (get_cpu() != 0)
smp_call_function_single(0, __bcm_kona_smc, (void *)&data, 1);
else
__bcm_kona_smc(&data);
put_cpu();
return 0;
}