genode/base-hw/src/core/cpu/arm_v7.h

309 lines
7.9 KiB
C++

/*
* \brief CPU driver for core
* \author Martin stein
* \date 2011-11-03
*/
/*
* Copyright (C) 2011-2012 Genode Labs GmbH
*
* This file is part of the Genode OS framework, which is distributed
* under the terms of the GNU General Public License version 2.
*/
#ifndef _CPU__ARM_V7_H_
#define _CPU__ARM_V7_H_
/* core includes */
#include <cpu/arm.h>
#include <board.h>
namespace Arm_v7
{
using namespace Genode;
/**
* CPU driver for core
*/
struct Cpu : Arm::Cpu
{
/**
* Secure configuration register
*/
struct Scr : Register<32>
{
struct Ns : Bitfield<0, 1> { }; /* not secure */
/**
* Read register value
*/
static access_t read()
{
access_t v;
asm volatile ("mrc p15, 0, %[v], c1, c1, 0" : [v]"=r"(v) ::);
return v;
}
};
/**
* Non-secure access control register
*/
struct Nsacr : Register<32>
{
/************************************************
** Coprocessor 0-13 non-secure acccess enable **
************************************************/
struct Cpnsae10 : Bitfield<10, 1> { };
struct Cpnsae11 : Bitfield<11, 1> { };
};
/**
* System control register
*/
struct Sctlr : Arm::Cpu::Sctlr
{
struct Unused_0 : Bitfield<3,4> { }; /* shall be ~0 */
struct Sw : Bitfield<10,1> { }; /* support SWP and SWPB */
struct Unused_1 : Bitfield<16,1> { }; /* shall be ~0 */
struct Ha : Bitfield<17,1> { }; /* enable HW access flag */
struct Unused_2 : Bitfield<18,1> { }; /* shall be ~0 */
struct Unused_3 : Bitfield<22,2> { }; /* shall be ~0 */
struct Nmfi : Bitfield<27,1> { }; /* FIQs are non-maskable */
struct Tre : Bitfield<28,1> { }; /* remap TEX[2:1] for OS */
struct Afe : Bitfield<29,1> /* translation access perm. mode */
{
enum { FULL_RANGE_OF_PERMISSIONS = 0 };
};
struct Te : Bitfield<30,1> { }; /* do exceptions in Thumb state */
/**
* Static base value
*/
static access_t base_value()
{
return Unused_0::bits(~0) |
Unused_1::bits(~0) |
Unused_2::bits(~0) |
Unused_3::bits(~0);
}
/**
* Value for the first kernel run
*/
static access_t init_phys_kernel()
{
return base_value() |
Arm::Cpu::Sctlr::init_virt_kernel() |
Sw::bits(0) |
Ha::bits(0) |
Nmfi::bits(0) |
Tre::bits(0);
}
/**
* Value for the switch to virtual mode in kernel
*/
static access_t init_virt_kernel()
{
return base_value() |
Arm::Cpu::Sctlr::init_virt_kernel() |
Sw::bits(0) |
Ha::bits(0) |
Nmfi::bits(0) |
Tre::bits(0);
}
};
/**
* Translation table base register 0
*/
struct Ttbr0 : Arm::Cpu::Ttbr0
{
struct Nos : Bitfield<6,1> { }; /* not outer shareable */
struct Irgn_0 : Bitfield<6,1> /* inner cachable mode */
{
enum { NON_CACHEABLE = 0 };
};
/**
* Value for the switch to virtual mode in kernel
*
* \param sect_table pointer to initial section table
*/
static access_t init_virt_kernel(addr_t const sect_table)
{
return Arm::Cpu::Ttbr0::init_virt_kernel(sect_table) |
Nos::bits(0) |
Irgn_0::bits(Irgn_0::NON_CACHEABLE);
}
};
/**
* Translation table base control register
*/
struct Ttbcr : Arm::Cpu::Ttbcr
{
struct Pd0 : Bitfield<4,1> { }; /* disable walk for TTBR0 */
struct Pd1 : Bitfield<5,1> { }; /* disable walk for TTBR1 */
/**
* Value for the switch to virtual mode in kernel
*/
static access_t init_virt_kernel()
{
return Arm::Cpu::Ttbcr::init_virt_kernel() |
Pd0::bits(0) |
Pd1::bits(0);
}
};
/**
* Switch to the virtual mode in kernel
*
* \param section_table section translation table of the initial
* address space this function switches to
* \param process_id process ID of the initial address space
*/
static void init_virt_kernel(addr_t const section_table,
unsigned long const process_id)
{
Cidr::write(process_id);
Dacr::write(Dacr::init_virt_kernel());
Ttbr0::write(Ttbr0::init_virt_kernel(section_table));
Ttbcr::write(Ttbcr::init_virt_kernel());
Sctlr::write(Sctlr::init_virt_kernel());
}
/**
* Configure this module appropriately for the first kernel run
*/
static void init_phys_kernel()
{
Board::prepare_kernel();
Psr::write(Psr::init_kernel());
flush_tlb();
}
/**
* Wether we are in secure mode
*/
static bool secure_mode()
{
if (!Board::SECURITY_EXTENSION) return 0;
return !Cpu::Scr::Ns::get(Cpu::Scr::read());
}
/******************************
** Trustzone specific API **
******************************/
/**
* Set the exception-vector's base-address for the monitor mode
* software stack.
*
* \param addr address of the exception vector's base
*/
static inline void mon_exception_entry_at(addr_t const addr)
{
asm volatile ("mcr p15, 0, %[rd], c12, c0, 1" : : [rd] "r" (addr));
}
/**
* Enable access of co-processors cp10 and cp11 from non-secure mode.
*/
static inline void allow_coprocessor_nonsecure()
{
Nsacr::access_t rd = Nsacr::Cpnsae10::bits(1) |
Nsacr::Cpnsae11::bits(1);
asm volatile ("mcr p15, 0, %[rd], c1, c1, 2" : : [rd] "r" (rd));
}
};
}
/**************
** Arm::Cpu **
**************/
void Arm::Cpu::flush_data_caches()
{
/*
* FIXME This routine is taken from the ARMv7 reference manual by
* applying the inline-assembly framework and replacing 'Loop1'
* with '1:', 'Loop2' with '2:', 'Loop3' with '3:', 'Skip'
* with '4:' and 'Finished' with '5:'. It might get implemented
* with more beauty.
*/
asm volatile (
"mrc p15, 1, r0, c0, c0, 1\n" /* read CLIDR into R0 */
"ands r3, r0, #0x7000000\n"
"mov r3, r3, lsr #23\n" /* cache level value (naturally aligned) */
"beq 5f\n"
"mov r10, #0\n"
"1:\n"
"add r2, r10, r10, lsr #1\n" /* work out 3 x cachelevel */
"mov r1, r0, lsr r2\n" /* bottom 3 bits are the Cache type for this level */
"and r1, r1, #7\n" /* get those 3 bits alone */
"cmp r1, #2\n"
"blt 4f\n" /* no cache or only instruction cache at this level */
"mcr p15, 2, r10, c0, c0, 0\n" /* write CSSELR from R10 */
"isb\n" /* ISB to sync the change to the CCSIDR */
"mrc p15, 1, r1, c0, c0, 0\n" /* read current CCSIDR to R1 */
"and r2, r1, #0x7\n" /* extract the line length field */
"add r2, r2, #4\n" /* add 4 for the line length offset (log2 16 bytes) */
"ldr r4, =0x3ff\n"
"ands r4, r4, r1, lsr #3\n" /* R4 is the max number on the way size (right aligned) */
"clz r5, r4\n" /* R5 is the bit position of the way size increment */
"mov r9, r4\n" /* R9 working copy of the max way size (right aligned) */
"2:\n"
"ldr r7, =0x00007fff\n"
"ands r7, r7, r1, lsr #13\n" /* R7 is the max number of the index size (right aligned) */
"3:\n"
"orr r11, r10, r9, lsl r5\n" /* factor in the way number and cache number into R11 */
"orr r11, r11, r7, lsl r2\n" /* factor in the index number */
"mcr p15, 0, r11, c7, c10, 2\n" /* DCCSW, clean by set/way */
"subs r7, r7, #1\n" /* decrement the index */
"bge 3b\n"
"subs r9, r9, #1\n" /* decrement the way number */
"bge 2b\n"
"4:\n"
"add r10, r10, #2\n" /* increment the cache number */
"cmp r3, r10\n"
"bgt 1b\n"
"dsb\n"
"5:\n"
::: "r0", "r1", "r2", "r3", "r4",
"r5", "r7", "r9", "r10", "r11");
}
Arm::Cpu::Psr::access_t Arm::Cpu::Psr::init_user_with_trustzone()
{
return M::bits(M::USER) |
T::bits(T::ARM) |
F::bits(0) |
I::bits(1) |
A::bits(1) |
E::bits(E::LITTLE) |
J::bits(J::ARM);
}
#endif /* _CPU__ARM_V7_H_ */