From a08358dce9044c8c184e81b2be5be270e3a89c7e Mon Sep 17 00:00:00 2001
From: Martin Stein <martin.stein@genode-labs.com>
Date: Thu, 22 Oct 2015 17:06:00 +0200
Subject: [PATCH] sd_card & imx53: fix multiblock write termination
The manual termination of multi-block writes via "Stop Transmission" commands
seems to leave the card in a busy state sometimes. This causes errors on
subsequent commands. Thus, we have to synchronize manually with the
card-internal state via "Send State" commands. Additionally, the method
for issuing the manual "Stop Transmission" commands was refined.
Ref #1497
---
repos/os/src/drivers/sd_card/sd_card.h | 36 +++++++++++
.../src/drivers/sd_card/spec/imx53/esdhcv2.h | 61 ++++++++++++++++++-
2 files changed, 96 insertions(+), 1 deletion(-)
diff --git a/repos/os/src/drivers/sd_card/sd_card.h b/repos/os/src/drivers/sd_card/sd_card.h
index d18e62a024..25e2539a61 100644
--- a/repos/os/src/drivers/sd_card/sd_card.h
+++ b/repos/os/src/drivers/sd_card/sd_card.h
@@ -22,6 +22,34 @@ namespace Sd_card {
using namespace Genode;
+ /**
+ * Structure of the first word of a native mode R1 response
+ */
+ struct R1_response_0 : Register<32>
+ {
+ struct Ready_for_data : Bitfield<8, 1> { };
+ struct State : Bitfield<9, 4>
+ {
+ enum { PROGRAM = 7 };
+ };
+ struct Error : Bitfield<19, 1> { };
+
+ /**
+ * Return wether the card is ready for data
+ *
+ * \param resp R1 response, word 0
+ */
+ static bool card_ready(access_t const resp)
+ {
+ /*
+ * Check both ready bit and state because not all cards handle
+ * the status bits correctly.
+ */
+ return Ready_for_data::get(resp) &&
+ State::get(resp) != State::PROGRAM;
+ }
+ };
+
/**
* Returned by 'Sd_send_op_cond'
*/
@@ -149,6 +177,14 @@ namespace Sd_card {
}
};
+ struct Send_status : Command<13, RESPONSE_48_BIT>
+ {
+ struct Arg : Sd_card::Arg
+ {
+ struct Rca : Bitfield<16, 16> { };
+ };
+ };
+
struct Select_card : Command<7, RESPONSE_48_BIT>
{
struct Arg : Sd_card::Arg
diff --git a/repos/os/src/drivers/sd_card/spec/imx53/esdhcv2.h b/repos/os/src/drivers/sd_card/spec/imx53/esdhcv2.h
index a509595496..dec19f2f94 100644
--- a/repos/os/src/drivers/sd_card/spec/imx53/esdhcv2.h
+++ b/repos/os/src/drivers/sd_card/spec/imx53/esdhcv2.h
@@ -177,6 +177,8 @@ struct Esdhcv2 : Genode::Mmio
_48BIT_BUSY = 3,
};
};
+ struct Cccen : Bitfield<19, 1> { };
+ struct Cicen : Bitfield<20, 1> { };
struct Dpsel : Bitfield<21, 1> { };
struct Cmdtyp : Bitfield<22, 2>
{
@@ -626,6 +628,57 @@ struct Esdhcv2_controller : private Esdhcv2, public Sd_card::Host_controller
return true;
}
+ int _wait_for_card_ready_mbw()
+ {
+ /*
+ * Poll card status
+ *
+ * The maximum number of attempts and the delay between two attempts are
+ * freely chosen.
+ */
+ using namespace Sd_card;
+ unsigned attempts = 5;
+ unsigned constexpr attempts_delay_us = 100000;
+ while (1) {
+ if (!attempts) {
+ PERR("Reading card status after multiblock write failed");
+ return -1;
+ }
+ /* assemble argument register value */
+ Send_status::Arg::access_t cmdarg = 0;
+ Send_status::Arg::Rca::set(cmdarg, _card_info.rca());
+
+ /* assemble command register value */
+ Xfertyp::access_t xfertyp = 0;
+ Xfertyp::Cmdinx::set(xfertyp, Send_status::INDEX);
+ Xfertyp::Cicen::set(xfertyp, 1);
+ Xfertyp::Cccen::set(xfertyp, 1);
+ Xfertyp::Rsptyp::set(xfertyp, Xfertyp::Rsptyp::_48BIT);
+ Xfertyp::Msbsel::set(xfertyp, 1);
+ Xfertyp::Bcen::set(xfertyp, 1);
+ Xfertyp::Dmaen::set(xfertyp, 1);
+
+ /* send command as soon as the host allows it */
+ if (_wait_for_cmd_allowed()) { return -1; }
+ write<Cmdarg>(cmdarg);
+ write<Xfertyp>(xfertyp);
+
+ /* wait for command completion */
+ if (_wait_for_cmd_complete()) { return -1; }
+
+ /* check for errors */
+ R1_response_0::access_t const resp = read<Cmdrsp0>();
+ if (R1_response_0::Error::get(resp)) {
+ PERR("Reading card status after multiblock write failed");
+ return -1;
+ }
+ /* if card is in a ready state, return success, retry otherwise */
+ if (R1_response_0::card_ready(resp)) { break; }
+ _delayer.usleep(attempts_delay_us);
+ }
+ return 0;
+ }
+
/**
* Abort transmission by manually issuing stop command
*
@@ -637,7 +690,12 @@ struct Esdhcv2_controller : private Esdhcv2, public Sd_card::Host_controller
Xfertyp::access_t xfertyp = 0;
Xfertyp::Cmdinx::set(xfertyp, Sd_card::Stop_transmission::INDEX);
Xfertyp::Cmdtyp::set(xfertyp, Xfertyp::Cmdtyp::ABORT_CMD12);
- Xfertyp::Rsptyp::set(xfertyp, Xfertyp::Rsptyp::_48BIT);
+ Xfertyp::Cccen::set(xfertyp, 1);
+ Xfertyp::Cicen::set(xfertyp, 1);
+ Xfertyp::Rsptyp::set(xfertyp, Xfertyp::Rsptyp::_48BIT_BUSY);
+ Xfertyp::Msbsel::set(xfertyp, 1);
+ Xfertyp::Bcen::set(xfertyp, 1);
+ Xfertyp::Dmaen::set(xfertyp, 1);
write<Xfertyp>(xfertyp);
return _wait_for_cmd_complete();
}
@@ -686,6 +744,7 @@ struct Esdhcv2_controller : private Esdhcv2, public Sd_card::Host_controller
* manually.
*/
if (!_abort_transmission()) { return false; }
+ if (_wait_for_card_ready_mbw()) { return false; }
}
return true;
}