diff --git a/drivers/gpu/drm/meson/Makefile b/drivers/gpu/drm/meson/Makefile index c389e2399133..fb7f5440fe57 100644 --- a/drivers/gpu/drm/meson/Makefile +++ b/drivers/gpu/drm/meson/Makefile @@ -1,6 +1,7 @@ # SPDX-License-Identifier: GPL-2.0-only meson-drm-y := meson_drv.o meson_plane.o meson_crtc.o meson_venc_cvbs.o meson-drm-y += meson_viu.o meson_vpp.o meson_venc.o meson_vclk.o meson_overlay.o +meson-drm-y += meson_rdma.o obj-$(CONFIG_DRM_MESON) += meson-drm.o obj-$(CONFIG_DRM_MESON_DW_HDMI) += meson_dw_hdmi.o diff --git a/drivers/gpu/drm/meson/meson_drv.h b/drivers/gpu/drm/meson/meson_drv.h index 3287282450a9..ea39be913c0f 100644 --- a/drivers/gpu/drm/meson/meson_drv.h +++ b/drivers/gpu/drm/meson/meson_drv.h @@ -123,6 +123,12 @@ struct meson_drm { bool venc_repeat; bool hdmi_use_enci; } venc; + + struct { + dma_addr_t addr_phys; + uint32_t *addr; + unsigned int offset; + } rdma; }; static inline int meson_vpu_is_compatible(struct meson_drm *priv, diff --git a/drivers/gpu/drm/meson/meson_rdma.c b/drivers/gpu/drm/meson/meson_rdma.c new file mode 100644 index 000000000000..25b34b1e72a7 --- /dev/null +++ b/drivers/gpu/drm/meson/meson_rdma.c @@ -0,0 +1,135 @@ +// SPDX-License-Identifier: GPL-2.0+ +/* + * Copyright (C) 2019 BayLibre, SAS + * Author: Neil Armstrong + */ + +#include +#include + +#include "meson_drv.h" +#include "meson_registers.h" +#include "meson_rdma.h" + +/* + * The VPU embeds a "Register DMA" that can write a sequence of registers + * on the VPU AHB bus, either manually or triggered by an internal IRQ + * event like VSYNC or a line input counter. + * The initial implementation handles a single channel (over 8), triggered + * by the VSYNC irq and does not handle the RDMA irq. + */ + +#define RDMA_DESC_SIZE (sizeof(uint32_t) * 2) + +int meson_rdma_init(struct meson_drm *priv) +{ + if (!priv->rdma.addr) { + /* Allocate a PAGE buffer */ + priv->rdma.addr = + dma_alloc_coherent(priv->dev, SZ_4K, + &priv->rdma.addr_phys, + GFP_KERNEL); + if (!priv->rdma.addr) + return -ENOMEM; + } + + priv->rdma.offset = 0; + + writel_relaxed(RDMA_CTRL_SW_RESET, + priv->io_base + _REG(RDMA_CTRL)); + writel_relaxed(RDMA_DEFAULT_CONFIG | + FIELD_PREP(RDMA_CTRL_AHB_WR_BURST, 3) | + FIELD_PREP(RDMA_CTRL_AHB_RD_BURST, 0), + priv->io_base + _REG(RDMA_CTRL)); + + return 0; +} + +void meson_rdma_free(struct meson_drm *priv) +{ + if (!priv->rdma.addr && !priv->rdma.addr_phys) + return; + + meson_rdma_stop(priv); + + dma_free_coherent(priv->dev, SZ_4K, + priv->rdma.addr, priv->rdma.addr_phys); + + priv->rdma.addr = NULL; + priv->rdma.addr_phys = (dma_addr_t)NULL; +} + +void meson_rdma_setup(struct meson_drm *priv) +{ + /* Channel 1: Write Flag, No Address Increment */ + writel_bits_relaxed(RDMA_ACCESS_RW_FLAG_CHAN1 | + RDMA_ACCESS_ADDR_INC_CHAN1, + RDMA_ACCESS_RW_FLAG_CHAN1, + priv->io_base + _REG(RDMA_ACCESS_AUTO)); +} + +void meson_rdma_stop(struct meson_drm *priv) +{ + writel_bits_relaxed(RDMA_IRQ_CLEAR_CHAN1, + RDMA_IRQ_CLEAR_CHAN1, + priv->io_base + _REG(RDMA_CTRL)); + + /* Stop Channel 1 */ + writel_bits_relaxed(RDMA_ACCESS_TRIGGER_CHAN1, + FIELD_PREP(RDMA_ACCESS_ADDR_INC_CHAN1, + RDMA_ACCESS_TRIGGER_STOP), + priv->io_base + _REG(RDMA_ACCESS_AUTO)); +} + +void meson_rdma_reset(struct meson_drm *priv) +{ + meson_rdma_stop(priv); + + priv->rdma.offset = 0; +} + +static void meson_rdma_writel(struct meson_drm *priv, uint32_t val, + uint32_t reg) +{ + if (priv->rdma.offset >= (SZ_4K / RDMA_DESC_SIZE)) { + dev_warn_once(priv->dev, "%s: overflow\n", __func__); + return; + } + + priv->rdma.addr[priv->rdma.offset++] = reg; + priv->rdma.addr[priv->rdma.offset++] = val; +} + +/* + * This will add the register to the RDMA buffer and write it to the + * hardware at the same time. + * When meson_rdma_flush is called, the RDMA will replay the register + * writes in order. + */ +void meson_rdma_writel_sync(struct meson_drm *priv, uint32_t val, uint32_t reg) +{ + meson_rdma_writel(priv, val, reg); + + writel_relaxed(val, priv->io_base + _REG(reg)); +} + +void meson_rdma_flush(struct meson_drm *priv) +{ + meson_rdma_stop(priv); + + /* Start of Channel 1 register writes buffer */ + writel(priv->rdma.addr_phys, + priv->io_base + _REG(RDMA_AHB_START_ADDR_1)); + + /* Last byte on Channel 1 register writes buffer */ + writel(priv->rdma.addr_phys + (priv->rdma.offset * RDMA_DESC_SIZE) - 1, + priv->io_base + _REG(RDMA_AHB_END_ADDR_1)); + + /* Trigger Channel 1 on VSYNC event */ + writel_bits_relaxed(RDMA_ACCESS_TRIGGER_CHAN1, + FIELD_PREP(RDMA_ACCESS_TRIGGER_CHAN1, + RDMA_ACCESS_TRIGGER_VSYNC), + priv->io_base + _REG(RDMA_ACCESS_AUTO)); + + priv->rdma.offset = 0; +} diff --git a/drivers/gpu/drm/meson/meson_rdma.h b/drivers/gpu/drm/meson/meson_rdma.h new file mode 100644 index 000000000000..3870bff7b47f --- /dev/null +++ b/drivers/gpu/drm/meson/meson_rdma.h @@ -0,0 +1,21 @@ +/* SPDX-License-Identifier: GPL-2.0+ */ +/* + * Copyright (C) 2019 BayLibre, SAS + * Author: Neil Armstrong + */ + +#ifndef __MESON_RDMA_H +#define __MESON_RDMA_H + +#include "meson_drv.h" + +int meson_rdma_init(struct meson_drm *priv); +void meson_rdma_free(struct meson_drm *priv); +void meson_rdma_setup(struct meson_drm *priv); +void meson_rdma_reset(struct meson_drm *priv); +void meson_rdma_stop(struct meson_drm *priv); + +void meson_rdma_writel_sync(struct meson_drm *priv, uint32_t val, uint32_t reg); +void meson_rdma_flush(struct meson_drm *priv); + +#endif /* __MESON_RDMA_H */