static int tegra_spi_dma_finish(struct tegra_spi_channel *spi) { int ret; unsigned int todo; struct apb_dma * const apb_dma = (struct apb_dma *)TEGRA_APB_DMA_BASE; todo = read32(&spi->dma_in->regs->wcount); if (spi->dma_in) { while ((read32(&spi->dma_in->regs->dma_byte_sta) < todo) || dma_busy(spi->dma_in)) ; dma_stop(spi->dma_in); clrbits_le32(&spi->regs->command1, SPI_CMD1_RX_EN); /* Disable secure access for the channel. */ clrbits_le32(&apb_dma->security_reg, SECURITY_EN_BIT(spi->dma_in->num)); dma_release(spi->dma_in); } if (spi->dma_out) { while ((read32(&spi->dma_out->regs->dma_byte_sta) < todo) || dma_busy(spi->dma_out)) ; clrbits_le32(&spi->regs->command1, SPI_CMD1_TX_EN); dma_stop(spi->dma_out); /* Disable secure access for the channel. */ clrbits_le32(&apb_dma->security_reg, SECURITY_EN_BIT(spi->dma_out->num)); dma_release(spi->dma_out); } if (fifo_error(spi)) { printk(BIOS_ERR, "%s: ERROR:\n", __func__); dump_dma_regs(spi->dma_out); dump_dma_regs(spi->dma_in); dump_spi_regs(spi); dump_fifo_status(spi); ret = -1; goto done; } ret = 0; done: spi->dma_in = NULL; spi->dma_out = NULL; return ret; }
static int tegra_spi_dma_finish(struct tegra_spi_channel *spi) { int ret; unsigned int todo; todo = read32(&spi->dma_in->regs->wcount); if (spi->dma_in) { while ((read32(&spi->dma_in->regs->dma_byte_sta) < todo) || dma_busy(spi->dma_in)) ; /* this shouldn't take long, no udelay */ dma_stop(spi->dma_in); clrbits_le32(&spi->regs->command1, SPI_CMD1_RX_EN); dma_release(spi->dma_in); } if (spi->dma_out) { while ((read32(&spi->dma_out->regs->dma_byte_sta) < todo) || dma_busy(spi->dma_out)) spi_delay(spi, todo - spi_byte_count(spi)); clrbits_le32(&spi->regs->command1, SPI_CMD1_TX_EN); dma_stop(spi->dma_out); dma_release(spi->dma_out); } if (fifo_error(spi)) { printk(BIOS_ERR, "%s: ERROR:\n", __func__); dump_dma_regs(spi->dma_out); dump_dma_regs(spi->dma_in); dump_spi_regs(spi); dump_fifo_status(spi); ret = -1; goto done; } ret = 0; done: spi->dma_in = NULL; spi->dma_out = NULL; return ret; }
/* release a DMA channel */ void dma_release(struct apb_dma_channel * const channel) { int i; /* FIXME: make this "thread" friendly */ while (dma_busy(channel)) ; channel->in_use = 0; /* clear the global enable bit if no channels are in use */ for (i = 0; i < ARRAY_SIZE(apb_dma_channels); i++) { if (apb_dma_channels[i].in_use) return; } clrbits_le32(&apb_dma->command, APB_COMMAND_GEN); }