From 034dd340b08be1f2f0477ad16131d609f9dbd53c Mon Sep 17 00:00:00 2001 From: Linus Torvalds Date: Sun, 30 Aug 2026 09:22:00 -0700 Subject: Merge tag 'trace-v7.3-2' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace Pull tracing fixes from Steven Rostedt: - Fix error output of boot instance creation failure Currently if a boot instance creation fails, instead of printing out the name of the instance that failed, it prints "(null)". That is because it prints "cur_str" that had already been processed by strsep(). Print the saved name instead. While at it, print the error code of the failure. - Fix use-after-free for same named historgrams Histograms can be named so that they can be used in multiple events. But if the named histogram has a variable attached, the second event that uses the named histogram which duplicates it and needs to free the original after duplication leaves the old variable in place and still visible. If another histogram uses than variable, it will use the stale one which will try to reference the freed duplicate histogram and crash the kernel. Free the duplicate variables along with the duplicated histogram data. - Check return value of kthread_run() in event self test The events self tests uses a kthread for testing but does not check if it succeeded in creating a kthread. If the kthread creation were to fail, the code will still try to call kthread_stop() on the error returned. - Fix race between reading trace_pipe and updating subbuffer size If a user is reading the trace_pipe file at the same time they update the ring buffer sub-buffer size, can cause the trace_pipe read to read stale data. Add trace_access_lock() around updating the ring buffer sub-buffer size. - Fix eventfs_inode on failure path in creation of the events directory In the creation of the "events" directory, if after allocating the eventfs_inode a failure is detected, it calls cleanup_ei() which calls free_ei(). The free_ei() will test if eventfs_inode being freed has no children. It is a bug if it does. But on the failure case of the creation of the "events" directory, the children lists have not yet been initialized and the free will trigger a warning because list_empty() on an uninitialized list returns false. Move the initialization into init_ei() where it makes more sense and makes sure that a created eventfs_inode has its lists initialized upon creation. - Check return value of kthread_run() in ftrace direct sample code The sample code that shows how to use the ftrace direct calls does not test the return of kthread_run() to see if it succeeds. Return a failure if the kthread_run() doesn't succeed. - Clear user events state on fork in case of alloc failure On fork, the child gets a pointer to the parent's user events state. It makes a copy of it then updates the child's pointer to it. But if the allocation fails, the duplication function leaves the child with a pointer to its parent's descriptor. When the child cleans up its data, it will free the parent's descriptor while the parent is still using it. In the duplication function, set the child's user_event_mm to NULL before testing if the allocation succeeded, and when it exits it will not free the parent's descriptor. - Fix retry exhaustion in simple ring buffer reader swap simple_ring_buffer_swap_reader_page() starts with retry set to 8 and post-decrements it only after a failed link replacement. On the final attempt, a successful replacement leaves retry at zero, while a failed replacement leaves it at -1. But the check for success expects the retry value to be non-zero and exits with an error on zero. This is the opposite result. Fix it. - Fail nicely when the remote swap_reader_page() returns an error Currently, if the swap_reader_page() of a remote buffer fails, it triggers a WARN_ON_ONCE() and continues normally. Instead, have it exit with an error and a pr_warn() print instead of a full WARNING. * tag 'trace-v7.3-2' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace: ring-buffer: Stop remote reader update when page swap fails tracing: Fix retry exhaustion in simple ring buffer reader swap tracing/user_events: Clear copied tracing state before fork duplication samples/ftrace: Fix kthread_stop() on ERR_PTR in ftrace-direct-multi-modify samples/ftrace: Fix kthread_stop() on ERR_PTR in ftrace-direct-modify eventfs: Initialize ei->children and ei->list in init_ei() tracing: Fix use-after-free in trace_pipe read on sub-buffer order change tracing: Fix crash passing ERR_PTR to kthread_stop() tracing: Fix use-after-free with same-name named triggers tracing: Fix logged instance name on creation failure --- 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 | 522 ++++++++++ drivers/gpu/drm/mcde/mcde_dsi.c | 1242 ++++++++++++++++++++++++ drivers/gpu/drm/mcde/mcde_dsi_regs.h | 385 ++++++++ 9 files changed, 4612 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