From 7878289b269d41c8e611aa6d4519feae706e49f3 Mon Sep 17 00:00:00 2001 From: Ulf Hansson Date: Fri, 13 Jun 2014 13:21:38 +0200 Subject: [PATCH] mmc: mmci: Reverse IRQ handling for the arm_variant Commit "mmc: mmci: Handle CMD irq before DATA irq", caused an issue when using the ARM model of the PL181 and running QEMU. The bug was reported for the following QEMU version: $ qemu-system-arm -version QEMU emulator version 2.0.0 (Debian 2.0.0+dfsg-2ubuntu1.1), Copyright (c) 2003-2008 Fabrice Bellard To resolve the problem, let's restore the old behavior were the DATA irq is handled prior the CMD irq, but only for the arm_variant, which the problem was reported for. Reported-by: John Stultz Cc: Peter Maydell Cc: Russell King Tested-by: Kees Cook Tested-by: John Stultz Cc: # v3.15+ Signed-off-by: Ulf Hansson --- drivers/mmc/host/mmci.c | 12 ++++++++++-- 1 file changed, 10 insertions(+), 2 deletions(-) diff --git a/drivers/mmc/host/mmci.c b/drivers/mmc/host/mmci.c index 5d20bfba3e49..e4d470704150 100644 --- a/drivers/mmc/host/mmci.c +++ b/drivers/mmc/host/mmci.c @@ -74,6 +74,7 @@ static unsigned int fmax = 515633; * @pwrreg_nopower: bits in MMCIPOWER don't controls ext. power supply * @explicit_mclk_control: enable explicit mclk control in driver. * @qcom_fifo: enables qcom specific fifo pio read logic. + * @reversed_irq_handling: handle data irq before cmd irq. */ struct variant_data { unsigned int clkreg; @@ -97,6 +98,7 @@ struct variant_data { bool pwrreg_nopower; bool explicit_mclk_control; bool qcom_fifo; + bool reversed_irq_handling; }; static struct variant_data variant_arm = { @@ -105,6 +107,7 @@ static struct variant_data variant_arm = { .datalength_bits = 16, .pwrreg_powerup = MCI_PWR_UP, .f_max = 100000000, + .reversed_irq_handling = true, }; static struct variant_data variant_arm_extended_fifo = { @@ -1236,8 +1239,13 @@ static irqreturn_t mmci_irq(int irq, void *dev_id) dev_dbg(mmc_dev(host->mmc), "irq0 (data+cmd) %08x\n", status); - mmci_cmd_irq(host, host->cmd, status); - mmci_data_irq(host, host->data, status); + if (host->variant->reversed_irq_handling) { + mmci_data_irq(host, host->data, status); + mmci_cmd_irq(host, host->cmd, status); + } else { + mmci_cmd_irq(host, host->cmd, status); + mmci_data_irq(host, host->data, status); + } /* Don't poll for busy completion in irq context. */ if (host->busy_status)