From: Lucas Stach <l.stach-bIcnvbaLZ9MEGnE8C9+IrQ@public.gmane.org>
To: Philipp Zabel <p.zabel-bIcnvbaLZ9MEGnE8C9+IrQ@public.gmane.org>
Cc: David Airlie <airlied-cv59FeDIM0c@public.gmane.org>,
Rob Herring <robh+dt-DgEjT+Ai2ygdnm+yROfE0A@public.gmane.org>,
Mark Rutland <mark.rutland-5wv7dgnIgG8@public.gmane.org>,
dri-devel-PD4FTy7X32lNgt0PjOBp9y5qC8QIuHrW@public.gmane.org,
devicetree-u79uwXL29TY76Z2rM5mHXA@public.gmane.org,
kernel-bIcnvbaLZ9MEGnE8C9+IrQ@public.gmane.org,
patchwork-lst-bIcnvbaLZ9MEGnE8C9+IrQ@public.gmane.org
Subject: [PATCH 5/9] gpu: ipu-v3: add driver for Prefetch Resolve Gasket
Date: Fri, 17 Feb 2017 19:28:26 +0100 [thread overview]
Message-ID: <20170217182830.32618-6-l.stach@pengutronix.de> (raw)
In-Reply-To: <20170217182830.32618-1-l.stach-bIcnvbaLZ9MEGnE8C9+IrQ@public.gmane.org>
This adds support for the i.MX6 QUadPlus PRG unit. It glues together the
IPU and the PRE units.
Signed-off-by: Lucas Stach <l.stach-bIcnvbaLZ9MEGnE8C9+IrQ@public.gmane.org>
---
drivers/gpu/ipu-v3/Makefile | 2 +-
drivers/gpu/ipu-v3/ipu-prg.c | 413 +++++++++++++++++++++++++++++++++++++++++++
drivers/gpu/ipu-v3/ipu-prv.h | 3 +
include/video/imx-ipu-v3.h | 15 ++
4 files changed, 432 insertions(+), 1 deletion(-)
create mode 100644 drivers/gpu/ipu-v3/ipu-prg.c
diff --git a/drivers/gpu/ipu-v3/Makefile b/drivers/gpu/ipu-v3/Makefile
index 8ae90de46b4d..1ab9bceee755 100644
--- a/drivers/gpu/ipu-v3/Makefile
+++ b/drivers/gpu/ipu-v3/Makefile
@@ -2,4 +2,4 @@ obj-$(CONFIG_IMX_IPUV3_CORE) += imx-ipu-v3.o
imx-ipu-v3-objs := ipu-common.o ipu-cpmem.o ipu-csi.o ipu-dc.o ipu-di.o \
ipu-dp.o ipu-dmfc.o ipu-ic.o ipu-image-convert.o \
- ipu-pre.o ipu-smfc.o ipu-vdi.o
+ ipu-pre.o ipu-prg.o ipu-smfc.o ipu-vdi.o
diff --git a/drivers/gpu/ipu-v3/ipu-prg.c b/drivers/gpu/ipu-v3/ipu-prg.c
new file mode 100644
index 000000000000..c1e1ab0ec5c5
--- /dev/null
+++ b/drivers/gpu/ipu-v3/ipu-prg.c
@@ -0,0 +1,413 @@
+/*
+ * Copyright (c) 2016-2017 Lucas Stach, Pengutronix
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms and conditions of the GNU General Public License,
+ * version 2, as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
+ * more details.
+ */
+
+#include <drm/drm_fourcc.h>
+#include <linux/clk.h>
+#include <linux/err.h>
+#include <linux/mfd/syscon.h>
+#include <linux/mfd/syscon/imx6q-iomuxc-gpr.h>
+#include <linux/module.h>
+#include <linux/of.h>
+#include <linux/platform_device.h>
+#include <linux/regmap.h>
+#include <video/imx-ipu-v3.h>
+
+#include "ipu-prv.h"
+
+#define IPU_PRG_CTL 0x00
+#define IPU_PRG_CTL_BYPASS(i) (1 << (0 + i))
+#define IPU_PRG_CTL_SOFT_ARID_MASK 0x3
+#define IPU_PRG_CTL_SOFT_ARID_SHIFT(i) (8 + i * 2)
+#define IPU_PRG_CTL_SOFT_ARID(i, v) ((v & 0x3) << (8 + 2 * i))
+#define IPU_PRG_CTL_SO(i) (1 << (16 + i))
+#define IPU_PRG_CTL_VFLIP(i) (1 << (19 + i))
+#define IPU_PRG_CTL_BLOCK_MODE(i) (1 << (22 + i))
+#define IPU_PRG_CTL_CNT_LOAD_EN(i) (1 << (25 + i))
+#define IPU_PRG_CTL_SOFTRST (1 << 30)
+#define IPU_PRG_CTL_SHADOW_EN (1 << 31)
+
+#define IPU_PRG_STATUS 0x04
+#define IPU_PRG_STATUS_BUFFER0_READY(i) (1 << (0 + i * 2))
+#define IPU_PRG_STATUS_BUFFER1_READY(i) (1 << (1 + i * 2))
+
+#define IPU_PRG_QOS 0x08
+#define IPU_PRG_QOS_ARID_MASK 0xf
+#define IPU_PRG_QOS_ARID_SHIFT(i) (0 + i * 4)
+
+#define IPU_PRG_REG_UPDATE 0x0c
+#define IPU_PRG_REG_UPDATE_REG_UPDATE (1 << 0)
+
+#define IPU_PRG_STRIDE(i) (0x10 + i * 0x4)
+#define IPU_PRG_STRIDE_STRIDE_MASK 0x3fff
+
+#define IPU_PRG_CROP_LINE 0x1c
+
+#define IPU_PRG_THD 0x20
+
+#define IPU_PRG_BADDR(i) (0x24 + i * 0x4)
+
+#define IPU_PRG_OFFSET(i) (0x30 + i * 0x4)
+
+#define IPU_PRG_ILO(i) (0x3c + i * 0x4)
+
+#define IPU_PRG_HEIGHT(i) (0x48 + i * 0x4)
+#define IPU_PRG_HEIGHT_PRE_HEIGHT_MASK 0xfff
+#define IPU_PRG_HEIGHT_PRE_HEIGHT_SHIFT 0
+#define IPU_PRG_HEIGHT_IPU_HEIGHT_MASK 0xfff
+#define IPU_PRG_HEIGHT_IPU_HEIGHT_SHIFT 16
+
+struct ipu_prg_channel {
+ bool enabled;
+ int used_pre;
+};
+
+struct ipu_prg {
+ struct list_head list;
+ struct device *dev;
+ int id;
+
+ void __iomem *regs;
+ struct clk *clk_ipg, *clk_axi;
+ struct regmap *iomuxc_gpr;
+ struct ipu_pre *pres[3];
+
+ struct ipu_prg_channel chan[3];
+};
+
+static DEFINE_MUTEX(ipu_prg_list_mutex);
+static LIST_HEAD(ipu_prg_list);
+
+struct ipu_prg *
+ipu_prg_get_by_ipu_device(struct device *dev)
+{
+ struct device_node *prg_node = of_parse_phandle(dev->of_node,
+ "fsl,prg", 0);
+ struct ipu_prg *prg;
+
+ mutex_lock(&ipu_prg_list_mutex);
+ list_for_each_entry(prg, &ipu_prg_list, list) {
+ if (prg_node == prg->dev->of_node) {
+ mutex_unlock(&ipu_prg_list_mutex);
+ device_link_add(dev, prg->dev, DL_FLAG_AUTOREMOVE);
+ prg->id = of_alias_get_id(dev->of_node, "ipu");
+ return prg;
+ }
+ }
+ mutex_unlock(&ipu_prg_list_mutex);
+
+ return NULL;
+}
+
+int ipu_prg_max_active_channels(void)
+{
+ return ipu_pre_get_available_count();
+}
+
+bool ipu_prg_present(struct ipu_soc *ipu)
+{
+ if (ipu->prg_priv)
+ return true;
+
+ return false;
+}
+
+bool ipu_prg_format_supported(struct ipu_soc *ipu, uint32_t format,
+ uint64_t modifier)
+{
+ const struct drm_format_info *info = drm_format_info(format);
+
+ if (info->num_planes != 1)
+ return false;
+
+ return true;
+}
+
+int ipu_prg_enable(struct ipu_soc *ipu)
+{
+ struct ipu_prg *prg = ipu->prg_priv;
+ int ret;
+
+ if (!prg)
+ return 0;
+
+ ret = clk_prepare_enable(prg->clk_axi);
+ if (ret)
+ goto fail_disable_ipg;
+
+ return 0;
+
+fail_disable_ipg:
+ clk_disable_unprepare(prg->clk_ipg);
+
+ return ret;
+}
+
+void ipu_prg_disable(struct ipu_soc *ipu)
+{
+ struct ipu_prg *prg = ipu->prg_priv;
+
+ if (!prg)
+ return;
+
+ clk_disable_unprepare(prg->clk_axi);
+}
+
+static int ipu_prg_ipu_to_prg_chan(int ipu_chan)
+{
+ /*
+ * This isn't clearly documented in the RM, but IPU to PRG channel
+ * assignment is fixed, as only with this mapping the control signals
+ * match up.
+ */
+ switch (ipu_chan) {
+ case IPUV3_CHANNEL_MEM_BG_SYNC:
+ return 0;
+ case IPUV3_CHANNEL_MEM_FG_SYNC:
+ return 1;
+ case IPUV3_CHANNEL_MEM_DC_SYNC:
+ return 2;
+ default:
+ return -EINVAL;
+ }
+}
+
+static int ipu_prg_get_pre(struct ipu_prg *prg, int prg_chan)
+{
+ int i, ret;
+
+ /* channel 0 is special as it is hardwired to one of the PREs */
+ if (prg_chan == 0) {
+ ret = ipu_pre_get(prg->pres[0]);
+ if (ret)
+ goto fail;
+ prg->chan[prg_chan].used_pre = 0;
+ return 0;
+ }
+
+ for (i = 1; i < 3; i++) {
+ ret = ipu_pre_get(prg->pres[i]);
+ if (!ret) {
+ u32 val, mux;
+ int shift;
+
+ prg->chan[prg_chan].used_pre = i;
+
+ /* configure the PRE to PRG channel mux */
+ shift = (i == 1) ? 12 : 14;
+ mux = (prg->id << 1) | (prg_chan - 1);
+ regmap_update_bits(prg->iomuxc_gpr, IOMUXC_GPR5,
+ 0x3 << shift, mux << shift);
+
+ /* check other mux, must not point to same channel */
+ shift = (i == 1) ? 14 : 12;
+ regmap_read(prg->iomuxc_gpr, IOMUXC_GPR5, &val);
+ if (((val >> shift) & 0x3) == mux) {
+ regmap_update_bits(prg->iomuxc_gpr, IOMUXC_GPR5,
+ 0x3 << shift,
+ (mux ^ 0x1) << shift);
+ }
+
+ return 0;
+ }
+ }
+
+fail:
+ dev_err(prg->dev, "could not get PRE for PRG chan %d", prg_chan);
+ return ret;
+}
+
+static void ipu_prg_put_pre(struct ipu_prg *prg, int prg_chan)
+{
+ struct ipu_prg_channel *chan = &prg->chan[prg_chan];
+
+ ipu_pre_put(prg->pres[chan->used_pre]);
+ chan->used_pre = -1;
+}
+
+void ipu_prg_channel_disable(struct ipuv3_channel *ipu_chan)
+{
+ int prg_chan = ipu_prg_ipu_to_prg_chan(ipu_chan->num);
+ struct ipu_prg *prg = ipu_chan->ipu->prg_priv;
+ struct ipu_prg_channel *chan = &prg->chan[prg_chan];
+ u32 val;
+
+ if (!chan->enabled || prg_chan < 0)
+ return;
+
+ clk_prepare_enable(prg->clk_ipg);
+
+ val = readl(prg->regs + IPU_PRG_CTL);
+ val |= IPU_PRG_CTL_BYPASS(prg_chan);
+ writel(val, prg->regs + IPU_PRG_CTL);
+
+ val = IPU_PRG_REG_UPDATE_REG_UPDATE;
+ writel(val, prg->regs + IPU_PRG_REG_UPDATE);
+
+ clk_disable_unprepare(prg->clk_ipg);
+
+ ipu_prg_put_pre(prg, prg_chan);
+
+ chan->enabled = false;
+}
+
+int ipu_prg_channel_configure(struct ipuv3_channel *ipu_chan,
+ unsigned int axi_id, unsigned int width,
+ unsigned int height, unsigned int stride,
+ u32 format, unsigned long *eba)
+{
+ int prg_chan = ipu_prg_ipu_to_prg_chan(ipu_chan->num);
+ struct ipu_prg *prg = ipu_chan->ipu->prg_priv;
+ struct ipu_prg_channel *chan = &prg->chan[prg_chan];
+ u32 val;
+ int ret;
+
+ if (prg_chan < 0)
+ return prg_chan;
+
+ if (chan->enabled) {
+ ipu_pre_update(prg->pres[chan->used_pre], *eba);
+ return 0;
+ }
+
+ ret = ipu_prg_get_pre(prg, prg_chan);
+ if (ret)
+ return ret;
+
+ ipu_pre_configure(prg->pres[chan->used_pre],
+ width, height, stride, format, *eba);
+
+
+ ret = clk_prepare_enable(prg->clk_ipg);
+ if (ret) {
+ ipu_prg_put_pre(prg, prg_chan);
+ return ret;
+ }
+
+ val = (stride - 1) & IPU_PRG_STRIDE_STRIDE_MASK;
+ writel(val, prg->regs + IPU_PRG_STRIDE(prg_chan));
+
+ val = ((height & IPU_PRG_HEIGHT_PRE_HEIGHT_MASK) <<
+ IPU_PRG_HEIGHT_PRE_HEIGHT_SHIFT) |
+ ((height & IPU_PRG_HEIGHT_IPU_HEIGHT_MASK) <<
+ IPU_PRG_HEIGHT_IPU_HEIGHT_SHIFT);
+ writel(val, prg->regs + IPU_PRG_HEIGHT(prg_chan));
+
+ val = ipu_pre_get_baddr(prg->pres[chan->used_pre]);
+ *eba = val;
+ writel(val, prg->regs + IPU_PRG_BADDR(prg_chan));
+
+ val = readl(prg->regs + IPU_PRG_CTL);
+ /* counter load enable */
+ val |= IPU_PRG_CTL_CNT_LOAD_EN(prg_chan);
+ /* config AXI ID */
+ val &= ~(IPU_PRG_CTL_SOFT_ARID_MASK <<
+ IPU_PRG_CTL_SOFT_ARID_SHIFT(prg_chan));
+ val |= IPU_PRG_CTL_SOFT_ARID(prg_chan, axi_id);
+ /* enable channel */
+ val &= ~IPU_PRG_CTL_BYPASS(prg_chan);
+ writel(val, prg->regs + IPU_PRG_CTL);
+
+ val = IPU_PRG_REG_UPDATE_REG_UPDATE;
+ writel(val, prg->regs + IPU_PRG_REG_UPDATE);
+
+ clk_disable_unprepare(prg->clk_ipg);
+
+ chan->enabled = true;
+ return 0;
+}
+
+static int ipu_prg_probe(struct platform_device *pdev)
+{
+ struct device *dev = &pdev->dev;
+ struct resource *res;
+ struct ipu_prg *prg;
+ u32 val;
+ int i, ret;
+
+ prg = devm_kzalloc(dev, sizeof(*prg), GFP_KERNEL);
+ if (!prg)
+ return -ENOMEM;
+
+ res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+ prg->regs = devm_ioremap_resource(&pdev->dev, res);
+ if (IS_ERR(prg->regs))
+ return PTR_ERR(prg->regs);
+
+
+ prg->clk_ipg = devm_clk_get(dev, "ipg");
+ if (IS_ERR(prg->clk_ipg))
+ return PTR_ERR(prg->clk_ipg);
+
+ prg->clk_axi = devm_clk_get(dev, "axi");
+ if (IS_ERR(prg->clk_axi))
+ return PTR_ERR(prg->clk_axi);
+
+ prg->iomuxc_gpr =
+ syscon_regmap_lookup_by_compatible("fsl,imx6q-iomuxc-gpr");
+ if (IS_ERR(prg->iomuxc_gpr))
+ return PTR_ERR(prg->iomuxc_gpr);
+
+ for (i = 0; i < 3; i++) {
+ prg->pres[i] = ipu_pre_get_by_prg_device(dev, i);
+ if (!prg->pres[i])
+ return -EPROBE_DEFER;
+ }
+
+ ret = clk_prepare_enable(prg->clk_ipg);
+ if (ret)
+ return ret;
+
+ /* init to free running mode */
+ val = readl(prg->regs + IPU_PRG_CTL);
+ val |= IPU_PRG_CTL_SHADOW_EN;
+ writel(val, prg->regs + IPU_PRG_CTL);
+
+ /* disable address threshold */
+ writel(0xffffffff, prg->regs + IPU_PRG_THD);
+
+ clk_disable_unprepare(prg->clk_ipg);
+
+ prg->dev = dev;
+ platform_set_drvdata(pdev, prg);
+ mutex_lock(&ipu_prg_list_mutex);
+ list_add(&prg->list, &ipu_prg_list);
+ mutex_unlock(&ipu_prg_list_mutex);
+
+ return 0;
+}
+
+static int ipu_prg_remove(struct platform_device *pdev)
+{
+ struct ipu_prg *prg = platform_get_drvdata(pdev);
+
+ mutex_lock(&ipu_prg_list_mutex);
+ list_del(&prg->list);
+ mutex_unlock(&ipu_prg_list_mutex);
+
+ return 0;
+}
+
+static const struct of_device_id ipu_prg_dt_ids[] = {
+ { .compatible = "fsl,imx6qp-prg", },
+ { /* sentinel */ },
+};
+
+static struct platform_driver ipu_prg_drv = {
+ .probe = ipu_prg_probe,
+ .remove = ipu_prg_remove,
+ .driver = {
+ .name = "imx-ipu-prg",
+ .of_match_table = ipu_prg_dt_ids,
+ },
+};
+module_platform_driver(ipu_prg_drv);
diff --git a/drivers/gpu/ipu-v3/ipu-prv.h b/drivers/gpu/ipu-v3/ipu-prv.h
index 536a156a5eb6..0d1d2d667f3b 100644
--- a/drivers/gpu/ipu-v3/ipu-prv.h
+++ b/drivers/gpu/ipu-v3/ipu-prv.h
@@ -169,6 +169,7 @@ struct ipu_vdi;
struct ipu_image_convert_priv;
struct ipu_smfc_priv;
struct ipu_pre;
+struct ipu_prg;
struct ipu_devtype;
@@ -270,4 +271,6 @@ void ipu_pre_configure(struct ipu_pre *pre, unsigned int width,
unsigned int stride, u32 format, unsigned int bufaddr);
void ipu_pre_update(struct ipu_pre *pre, unsigned int bufaddr);
+struct ipu_prg *ipu_prg_get_by_ipu_device(struct device *dev);
+
#endif /* __IPU_PRV_H__ */
diff --git a/include/video/imx-ipu-v3.h b/include/video/imx-ipu-v3.h
index 228e32082097..3902323f8769 100644
--- a/include/video/imx-ipu-v3.h
+++ b/include/video/imx-ipu-v3.h
@@ -331,6 +331,21 @@ int ipu_dp_set_global_alpha(struct ipu_dp *dp, bool enable, u8 alpha,
bool bg_chan);
/*
+ * IPU Prefetch Resolve Gasket (prg) functions
+ */
+int ipu_prg_max_active_channels(void);
+bool ipu_prg_present(struct ipu_soc *ipu);
+bool ipu_prg_format_supported(struct ipu_soc *ipu, uint32_t format,
+ uint64_t modifier);
+int ipu_prg_enable(struct ipu_soc *ipu);
+void ipu_prg_disable(struct ipu_soc *ipu);
+void ipu_prg_channel_disable(struct ipuv3_channel *ipu_chan);
+int ipu_prg_channel_configure(struct ipuv3_channel *ipu_chan,
+ unsigned int axi_id, unsigned int width,
+ unsigned int height, unsigned int stride,
+ u32 format, unsigned long *eba);
+
+/*
* IPU CMOS Sensor Interface (csi) functions
*/
struct ipu_csi;
--
2.11.0
--
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next prev parent reply other threads:[~2017-02-17 18:28 UTC|newest]
Thread overview: 19+ messages / expand[flat|nested] mbox.gz Atom feed top
2017-02-17 18:28 [PATCH 0/9] ipu-v3/imx-drm PRG/PRE extension Lucas Stach
[not found] ` <20170217182830.32618-1-l.stach-bIcnvbaLZ9MEGnE8C9+IrQ@public.gmane.org>
2017-02-17 18:28 ` [PATCH 1/9] gpu: ipu-v3: remove AXI ID setting for IC channel Lucas Stach
2017-02-20 13:04 ` Philipp Zabel
2017-02-17 18:28 ` [PATCH 2/9] gpu: ipu-v3: add DT binding for the Prefetch Resolve Engine Lucas Stach
[not found] ` <20170217182830.32618-3-l.stach-bIcnvbaLZ9MEGnE8C9+IrQ@public.gmane.org>
2017-02-20 15:01 ` Philipp Zabel
2017-02-27 17:00 ` Rob Herring
2017-02-17 18:28 ` [PATCH 3/9] gpu: ipu-v3: add driver for " Lucas Stach
[not found] ` <20170217182830.32618-4-l.stach-bIcnvbaLZ9MEGnE8C9+IrQ@public.gmane.org>
2017-02-20 15:20 ` Philipp Zabel
2017-03-03 18:25 ` Lucas Stach
2017-03-06 8:42 ` Philipp Zabel
2017-02-17 18:28 ` [PATCH 4/9] gpu: ipu-v3: add DT binding for the Prefetch Resolve Gasket Lucas Stach
2017-02-27 17:02 ` Rob Herring
2017-02-17 18:28 ` Lucas Stach [this message]
2017-02-20 15:31 ` [PATCH 5/9] gpu: ipu-v3: add driver for " Philipp Zabel
2017-02-17 18:28 ` [PATCH 6/9] gpu: ipu-v3: extend the IPUv3 DT binding for i.MX6 QuadPlus Lucas Stach
2017-02-27 17:04 ` Rob Herring
2017-02-17 18:28 ` [PATCH 7/9] gpu: ipu-v3: hook up PRG unit Lucas Stach
2017-02-17 18:28 ` [PATCH 8/9] drm/imx: enable/disable PRG on CRTC enable/disable Lucas Stach
2017-02-17 18:28 ` [PATCH 9/9] drm/imx: use PRG/PRE when possible Lucas Stach
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