From a9e3760b0838299649c0d57cca44daaf40ba3c33 Mon Sep 17 00:00:00 2001 From: Tejun Heo Date: Mon, 14 Sep 2026 22:12:34 -1000 Subject: sched_ext: Maintain an online cid mask in the scheduler arena Schedulers on the default cid mapping treat [0, nr_online_cids) as the online set and restart on hotplug. Schedulers that install their own mapping with scx_bpf_cid_override() have no way to learn which cids are online: the count no longer identifies members and the CPU-form cpumask is unusable from cid programs. This is an obvious hole in the cid API. Add scx_bpf_online_cmask(), a kernel-maintained cmask in the scheduler's arena, allocated alongside the per-CPU scratch masks and populated after the cid mapping is finalized and before ops.init(), for child schedulers too. The pointer stays valid through ops.exit() with no reference to take. It is the arena offset as a void pointer, the same form struct_ops arena arguments arrive in. The verifier types the void return as a scalar for the program's arena cast. The mask follows the SCX hotplug notifications: seeded from cpu_active_mask and updated before ops.cid_online/offline() runs, so it lags cpu_online_mask only inside a hotplug transition. Updates walk the scheduler list under the lock that also serializes unlinking. Reads are live, not atomic snapshots. Root initialization excludes hotplug. v2: Reworded the getter kerneldoc (Andrea Righi). Signed-off-by: Tejun Heo Reviewed-by: Andrea Righi --- drivers/gpu/drm/mcde/Kconfig | 18 + drivers/gpu/drm/mcde/Makefile | 3 + drivers/gpu/drm/mcde/mcde_clk_div.c | 196 ++++ drivers/gpu/drm/mcde/mcde_display.c | 1523 ++++++++++++++++++++++++++++++ drivers/gpu/drm/mcde/mcde_display_regs.h | 605 ++++++++++++ drivers/gpu/drm/mcde/mcde_drm.h | 118 +++ drivers/gpu/drm/mcde/mcde_drv.c | 521 ++++++++++ drivers/gpu/drm/mcde/mcde_dsi.c | 1238 ++++++++++++++++++++++++ drivers/gpu/drm/mcde/mcde_dsi_regs.h | 385 ++++++++ 9 files changed, 4607 insertions(+) create mode 100644 drivers/gpu/drm/mcde/Kconfig create mode 100644 drivers/gpu/drm/mcde/Makefile create mode 100644 drivers/gpu/drm/mcde/mcde_clk_div.c create mode 100644 drivers/gpu/drm/mcde/mcde_display.c create mode 100644 drivers/gpu/drm/mcde/mcde_display_regs.h create mode 100644 drivers/gpu/drm/mcde/mcde_drm.h create mode 100644 drivers/gpu/drm/mcde/mcde_drv.c create mode 100644 drivers/gpu/drm/mcde/mcde_dsi.c create mode 100644 drivers/gpu/drm/mcde/mcde_dsi_regs.h (limited to 'drivers/gpu/drm/mcde') diff --git a/drivers/gpu/drm/mcde/Kconfig b/drivers/gpu/drm/mcde/Kconfig new file mode 100644 index 000000000..3516c8d2a --- /dev/null +++ b/drivers/gpu/drm/mcde/Kconfig @@ -0,0 +1,18 @@ +config DRM_MCDE + tristate "DRM Support for ST-Ericsson MCDE (Multichannel Display Engine)" + depends on DRM + depends on CMA + depends on ARM || COMPILE_TEST + depends on OF + depends on COMMON_CLK + select MFD_SYSCON + select DRM_CLIENT_SELECTION + select DRM_MIPI_DSI + select DRM_BRIDGE + select DRM_PANEL_BRIDGE + select DRM_KMS_HELPER + select DRM_GEM_DMA_HELPER + help + Choose this option for DRM support for the ST-Ericsson MCDE + Multi-Channel Display Engine. + If M is selected the module will be called mcde_drm. diff --git a/drivers/gpu/drm/mcde/Makefile b/drivers/gpu/drm/mcde/Makefile new file mode 100644 index 000000000..15d9c89a3 --- /dev/null +++ b/drivers/gpu/drm/mcde/Makefile @@ -0,0 +1,3 @@ +mcde_drm-y += mcde_drv.o mcde_dsi.o mcde_clk_div.o mcde_display.o + +obj-$(CONFIG_DRM_MCDE) += mcde_drm.o diff --git a/drivers/gpu/drm/mcde/mcde_clk_div.c b/drivers/gpu/drm/mcde/mcde_clk_div.c new file mode 100644 index 000000000..8c5af2677 --- /dev/null +++ b/drivers/gpu/drm/mcde/mcde_clk_div.c @@ -0,0 +1,196 @@ +// SPDX-License-Identifier: GPL-2.0 +#include +#include +#include + +#include "mcde_drm.h" +#include "mcde_display_regs.h" + +/* The MCDE internal clock dividers for FIFO A and B */ +struct mcde_clk_div { + struct clk_hw hw; + struct mcde *mcde; + u32 cr; + u32 cr_div; +}; + +static int mcde_clk_div_enable(struct clk_hw *hw) +{ + struct mcde_clk_div *cdiv = container_of(hw, struct mcde_clk_div, hw); + struct mcde *mcde = cdiv->mcde; + u32 val; + + spin_lock(&mcde->fifo_crx1_lock); + val = readl(mcde->regs + cdiv->cr); + /* + * Select the PLL72 (LCD) clock as parent + * FIXME: implement other parents. + */ + val &= ~MCDE_CRX1_CLKSEL_MASK; + val |= MCDE_CRX1_CLKSEL_CLKPLL72 << MCDE_CRX1_CLKSEL_SHIFT; + /* Internal clock */ + val |= MCDE_CRA1_CLKTYPE_TVXCLKSEL1; + + /* Clear then set the divider */ + val &= ~(MCDE_CRX1_BCD | MCDE_CRX1_PCD_MASK); + val |= cdiv->cr_div; + + writel(val, mcde->regs + cdiv->cr); + spin_unlock(&mcde->fifo_crx1_lock); + + return 0; +} + +static int mcde_clk_div_choose_div(struct clk_hw *hw, unsigned long rate, + unsigned long *prate, bool set_parent) +{ + int best_div = 1, div; + struct clk_hw *parent = clk_hw_get_parent(hw); + unsigned long best_prate = 0; + unsigned long best_diff = ~0ul; + int max_div = (1 << MCDE_CRX1_PCD_BITS) - 1; + + for (div = 1; div < max_div; div++) { + unsigned long this_prate, div_rate, diff; + + if (set_parent) + this_prate = clk_hw_round_rate(parent, rate * div); + else + this_prate = *prate; + div_rate = DIV_ROUND_UP_ULL(this_prate, div); + diff = abs(rate - div_rate); + + if (diff < best_diff) { + best_div = div; + best_diff = diff; + best_prate = this_prate; + } + } + + *prate = best_prate; + return best_div; +} + +static int mcde_clk_div_determine_rate(struct clk_hw *hw, + struct clk_rate_request *req) +{ + int div = mcde_clk_div_choose_div(hw, req->rate, + &req->best_parent_rate, true); + + req->rate = DIV_ROUND_UP_ULL(req->best_parent_rate, div); + + return 0; +} + +static unsigned long mcde_clk_div_recalc_rate(struct clk_hw *hw, + unsigned long prate) +{ + struct mcde_clk_div *cdiv = container_of(hw, struct mcde_clk_div, hw); + struct mcde *mcde = cdiv->mcde; + u32 cr; + int div; + + /* + * If the MCDE is not powered we can't access registers. + * It will come up with 0 in the divider register bits, which + * means "divide by 2". + */ + if (!regulator_is_enabled(mcde->epod)) + return DIV_ROUND_UP_ULL(prate, 2); + + cr = readl(mcde->regs + cdiv->cr); + if (cr & MCDE_CRX1_BCD) + return prate; + + /* 0 in the PCD means "divide by 2", 1 means "divide by 3" etc */ + div = cr & MCDE_CRX1_PCD_MASK; + div += 2; + + return DIV_ROUND_UP_ULL(prate, div); +} + +static int mcde_clk_div_set_rate(struct clk_hw *hw, unsigned long rate, + unsigned long prate) +{ + struct mcde_clk_div *cdiv = container_of(hw, struct mcde_clk_div, hw); + int div = mcde_clk_div_choose_div(hw, rate, &prate, false); + u32 cr = 0; + + /* + * We cache the CR bits to set the divide in the state so that + * we can call this before we can even write to the hardware. + */ + if (div == 1) { + /* Bypass clock divider */ + cr |= MCDE_CRX1_BCD; + } else { + div -= 2; + cr |= div & MCDE_CRX1_PCD_MASK; + } + cdiv->cr_div = cr; + + return 0; +} + +static const struct clk_ops mcde_clk_div_ops = { + .enable = mcde_clk_div_enable, + .recalc_rate = mcde_clk_div_recalc_rate, + .determine_rate = mcde_clk_div_determine_rate, + .set_rate = mcde_clk_div_set_rate, +}; + +int mcde_init_clock_divider(struct mcde *mcde) +{ + struct device *dev = mcde->dev; + struct mcde_clk_div *fifoa; + struct mcde_clk_div *fifob; + const char *parent_name; + struct clk_init_data fifoa_init = { + .name = "fifoa", + .ops = &mcde_clk_div_ops, + .parent_names = &parent_name, + .num_parents = 1, + .flags = CLK_SET_RATE_PARENT, + }; + struct clk_init_data fifob_init = { + .name = "fifob", + .ops = &mcde_clk_div_ops, + .parent_names = &parent_name, + .num_parents = 1, + .flags = CLK_SET_RATE_PARENT, + }; + int ret; + + spin_lock_init(&mcde->fifo_crx1_lock); + parent_name = __clk_get_name(mcde->lcd_clk); + + /* Allocate 2 clocks */ + fifoa = devm_kzalloc(dev, sizeof(*fifoa), GFP_KERNEL); + if (!fifoa) + return -ENOMEM; + fifob = devm_kzalloc(dev, sizeof(*fifob), GFP_KERNEL); + if (!fifob) + return -ENOMEM; + + fifoa->mcde = mcde; + fifoa->cr = MCDE_CRA1; + fifoa->hw.init = &fifoa_init; + ret = devm_clk_hw_register(dev, &fifoa->hw); + if (ret) { + dev_err(dev, "error registering FIFO A clock divider\n"); + return ret; + } + mcde->fifoa_clk = fifoa->hw.clk; + + fifob->mcde = mcde; + fifob->cr = MCDE_CRB1; + fifob->hw.init = &fifob_init; + ret = devm_clk_hw_register(dev, &fifob->hw); + if (ret) { + dev_err(dev, "error registering FIFO B clock divider\n"); + return ret; + } + mcde->fifob_clk = fifob->hw.clk; + + return 0; +} diff --git a/drivers/gpu/drm/mcde/mcde_display.c b/drivers/gpu/drm/mcde/mcde_display.c new file mode 100644 index 000000000..257a6e84d --- /dev/null +++ b/drivers/gpu/drm/mcde/mcde_display.c @@ -0,0 +1,1523 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * Copyright (C) 2018 Linus Walleij + * Parts of this file were based on the MCDE driver by Marcus Lorentzon + * (C) ST-Ericsson SA 2013 + */ +#include +#include +#include +#include +#include + +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include