From ad914a3ec5f1b8c4f97a00f94e11bb20f99a901b Mon Sep 17 00:00:00 2001 From: Dongxiao Xu Date: Sun, 31 May 2009 14:43:55 +0800 Subject: Staging: heci: fix setting h_is bit in h_csr register Host software could issue interrupts to ME firmware, using H_IG bit. While Setting H_IG bit, host software should preserve all the other bits in H_CSR unchanged. In the original function which sets H_CSR register, they first read the register, then set some bits, and write the whole 32bits back to the register. And that the special behavior of H_IS (write-one-to-zero) causes problem. This patch fixes the issue in the following ways: - Modify heci_set_csr_register() function so that it doesn't change H_IS bit. - Add interface heci_csr_clear_his() to clear H_IS bit. This function is called after H_IS checking (dev->host_hw_state & H_IS == H_IS). - In original heci_csr_disable_interrupts() function, it not only clears H_IE bit, sometimes it also clears H_IS bit. This patch separates the two parts. - Avoid calling write_heci_register() function to set H_CSR register directly, and instead using heci_set_csr_register() function Signed-off-by: Dongxiao Xu Signed-off-by: Greg Kroah-Hartman --- drivers/staging/heci/heci_init.c | 4 ++-- drivers/staging/heci/heci_interface.c | 17 +++++++++++++++-- drivers/staging/heci/heci_interface.h | 1 + drivers/staging/heci/interrupt.c | 6 ++++++ 4 files changed, 24 insertions(+), 4 deletions(-) diff --git a/drivers/staging/heci/heci_init.c b/drivers/staging/heci/heci_init.c index 06ea1967e0e..427f55d7b26 100644 --- a/drivers/staging/heci/heci_init.c +++ b/drivers/staging/heci/heci_init.c @@ -249,7 +249,7 @@ int heci_hw_init(struct iamt_heci_device *dev) if ((dev->host_hw_state & H_IS) == H_IS) { /* acknowledge interrupt and stop interupts */ - heci_set_csr_register(dev); + heci_csr_clear_his(dev); } dev->recvd_msg = 0; DBG("reset in start the heci device.\n"); @@ -354,7 +354,7 @@ void heci_reset(struct iamt_heci_device *dev, int interrupts) dev->host_hw_state &= ~H_RST; dev->host_hw_state |= H_IG; - write_heci_register(dev, H_CSR, dev->host_hw_state); + heci_set_csr_register(dev); DBG("currently saved host_hw_state = 0x%08x.\n", dev->host_hw_state); diff --git a/drivers/staging/heci/heci_interface.c b/drivers/staging/heci/heci_interface.c index c5f51a7ddf2..03e1df1a88a 100644 --- a/drivers/staging/heci/heci_interface.c +++ b/drivers/staging/heci/heci_interface.c @@ -44,12 +44,15 @@ /** - * heci_set_csr_register - write H_CSR register to the heci device + * heci_set_csr_register - write H_CSR register to the heci device, + * and ignore the H_IS bit for it is write-one-to-zero. * * @dev: device object for our driver */ void heci_set_csr_register(struct iamt_heci_device *dev) { + if ((dev->host_hw_state & H_IS) == H_IS) + dev->host_hw_state &= ~H_IS; write_heci_register(dev, H_CSR, dev->host_hw_state); dev->host_hw_state = read_heci_register(dev, H_CSR); } @@ -76,6 +79,16 @@ void heci_csr_disable_interrupts(struct iamt_heci_device *dev) heci_set_csr_register(dev); } +/** + * heci_csr_clear_his - clear H_IS bit in H_CSR + * + * @dev: device object for our driver + */ +void heci_csr_clear_his(struct iamt_heci_device *dev) +{ + write_heci_register(dev, H_CSR, dev->host_hw_state); + dev->host_hw_state = read_heci_register(dev, H_CSR); +} /** * _host_get_filled_slots - get number of device filled buffer slots @@ -185,7 +198,7 @@ int heci_write_message(struct iamt_heci_device *dev, } dev->host_hw_state |= H_IG; - write_heci_register(dev, H_CSR, dev->host_hw_state); + heci_set_csr_register(dev); dev->me_hw_state = read_heci_register(dev, ME_CSR_HA); if ((dev->me_hw_state & ME_RDY_HRA) != ME_RDY_HRA) return 0; diff --git a/drivers/staging/heci/heci_interface.h b/drivers/staging/heci/heci_interface.h index d9193cf6d9e..34db7e52b8e 100644 --- a/drivers/staging/heci/heci_interface.h +++ b/drivers/staging/heci/heci_interface.h @@ -133,6 +133,7 @@ enum client_disconnect_status_types{ void heci_set_csr_register(struct iamt_heci_device *dev); void heci_csr_enable_interrupts(struct iamt_heci_device *dev); void heci_csr_disable_interrupts(struct iamt_heci_device *dev); +void heci_csr_clear_his(struct iamt_heci_device *dev); void heci_read_slots(struct iamt_heci_device *dev, unsigned char *buffer, unsigned long buffer_length); diff --git a/drivers/staging/heci/interrupt.c b/drivers/staging/heci/interrupt.c index b7ce73be826..3a510ed3a3d 100644 --- a/drivers/staging/heci/interrupt.c +++ b/drivers/staging/heci/interrupt.c @@ -92,6 +92,9 @@ irqreturn_t heci_isr_interrupt(int irq, void *dev_id) /* disable interrupts */ heci_csr_disable_interrupts(dev); + /* clear H_IS bit in H_CSR */ + heci_csr_clear_his(dev); + /* * Our device interrupted, schedule work the heci_bh_handler * to handle the interrupt processing. This needs to be a @@ -251,6 +254,9 @@ end: /* acknowledge interrupt and disable interrupts */ heci_csr_disable_interrupts(dev); + /* clear H_IS bit in H_CSR */ + heci_csr_clear_his(dev); + PREPARE_WORK(&dev->work, heci_bh_handler); DBG("schedule work the heci_bh_handler.\n"); rets = schedule_work(&dev->work); -- cgit v1.2.3