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os: detection of standard-capacity SD cards 

This patch enhances the generic SD-card protocol implementation in
sd-card.h with the ability to handle the version 1.0 of the CSD register
(containing the capacity information of older SD cards).
This commit is contained in:
Norman Feske 2015-04-04 17:52:58 +02:00 committed by Christian Helmuth
parent 26442f782b
commit 77cba65b7a
1 changed files with 53 additions and 13 deletions
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66
repos/os/src/drivers/sd_card/sd_card.h
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@ -45,14 +45,20 @@ namespace Sd_card {
{
enum { BIT_BASE = 1*sizeof(access_t)*8 };
struct Device_size_lo : Bitfield<48 - BIT_BASE, 16> { };
struct V2_device_size_lo : Bitfield<48 - BIT_BASE, 16> { };
struct V1_c_size_lo : Bitfield<62 - BIT_BASE, 2> { };
struct V1_c_size_mult : Bitfield<47 - BIT_BASE, 3> { };
};
struct Csd2 : Register<32>
{
enum { BIT_BASE = 2*sizeof(access_t)*8 };
struct Device_size_hi : Bitfield<64 - BIT_BASE, 6> { };
struct V2_device_size_hi : Bitfield<64 - BIT_BASE, 6> { };
struct V1_read_bl_len : Bitfield<80 - BIT_BASE, 4> { };
struct V1_c_size_hi : Bitfield<64 - BIT_BASE, 10> { };
};
struct Csd3 : Register<32>
@ -61,7 +67,7 @@ namespace Sd_card {
struct Version : Bitfield<126 - BIT_BASE, 2>
{
enum { HIGH_CAPACITY = 1, EXT_CSD = 3 };
enum { STANDARD_CAPACITY = 0, HIGH_CAPACITY = 1, EXT_CSD = 3 };
};
struct Mmc_spec_vers : Bitfield<122 - BIT_BASE, 4> { };
@ -394,6 +400,48 @@ namespace Sd_card {
return _issue_command(command.base());
}
private:
/**
* Extract capacity information from CSD register
*
* \throw Detection_failed
* \return capacity in 512-byte blocks
*/
size_t _sd_card_device_size(Csd const csd)
{
/*
* The capacity is reported via the CSD register. There are
* two versions of this register. Standard-capacity cards
* use version 1 whereas high-capacity cards use version 2.
*/
if (Csd3::Version::get(csd.csd3) == Csd3::Version::STANDARD_CAPACITY) {
/*
* Calculation of the capacity according to the
* "Physical Layer Simplified Specification Version 4.10",
* Section 5.3.2.
*/
size_t const read_bl_len = Csd2::V1_read_bl_len::get(csd.csd2);
size_t const c_size = (Csd2::V1_c_size_hi::get(csd.csd2) << 2)
| Csd1::V1_c_size_lo::get(csd.csd1);
size_t const c_size_mult = Csd1::V1_c_size_mult::get(csd.csd1);
size_t const mult = 1 << (c_size_mult + 2);
size_t const block_len = 1 << read_bl_len;
size_t const capacity = (c_size + 1)*mult*block_len;
return capacity;
}
if (Csd3::Version::get(csd.csd3) == Csd3::Version::HIGH_CAPACITY)
return ((Csd2::V2_device_size_hi::get(csd.csd2) << 16)
| Csd1::V2_device_size_lo::get(csd.csd1)) + 1;
PERR("Could not detect SD-card capacity");
throw Detection_failed();
}
protected:
/**
@ -410,7 +458,7 @@ namespace Sd_card {
Cid const cid = _read_cid();
PLOG("CID: 0x%08x 0x%08x 0x%08x 0x%08x",
cid.raw_0, cid.raw_1, cid.raw_2, cid.raw_3);
cid.raw_3, cid.raw_2, cid.raw_1, cid.raw_0);
if (!issue_command(Send_relative_addr())) {
PERR("Send_relative_addr timed out");
@ -427,20 +475,12 @@ namespace Sd_card {
Csd const csd = _read_csd();
if (Csd3::Version::get(csd.csd3) != Csd3::Version::HIGH_CAPACITY) {
PERR("Could not detect high-capacity card");
throw Detection_failed();
}
size_t const device_size = ((Csd2::Device_size_hi::get(csd.csd2) << 16)
| Csd1::Device_size_lo::get(csd.csd1)) + 1;
if (!issue_command(Select_card(rca))) {
PERR("Select_card failed");
throw Detection_failed();
}
return Card_info(rca, device_size / 2);
return Card_info(rca, _sd_card_device_size(csd) / 2);
}
Card_info _detect_mmc()