bus: mvebu-mbus: Avoid setting an undefined window size (09752a12) · Commits · 戴 / test

The mbus hardware requires a power of two size, and size aligned base. Currently, if a non-power of two is passed in to the low level routines they configure the register in a way that results in undefined behaviour. Call WARN and return EINVAL instead. Also, update the debugfs routines to show a message if there is an invalid register setting. All together this makes the recent problems with silent failure of PCI very obvious, noisy and debuggable. Signed-off-by:

Jason Gunthorpe <jgunthorpe@obsidianresearch.com> Signed-off-by:

Thomas Petazzoni <thomas.petazzoni@free-electrons.com> Link: https://lkml.kernel.org/r/1397823593-1932-6-git-send-email-thomas.petazzoni@free-electrons.com Signed-off-by:

Jason Cooper <jason@lakedaemon.net>

drivers/bus/mvebu-mbus.c

+16 −0

Original line number	Diff line number	Diff line
		@@ -56,6 +56,7 @@
		#include <linux/of.h>
		#include <linux/of_address.h>
		#include <linux/debugfs.h>
		#include <linux/log2.h>

		/*
		* DDR target is the same on all platforms.
		@@ -266,6 +267,17 @@ static int mvebu_mbus_setup_window(struct mvebu_mbus_state *mbus,
		mbus->soc->win_cfg_offset(win);
		u32 ctrl, remap_addr;

		if (!is_power_of_2(size)) {
		WARN(true, "Invalid MBus window size: 0x%zx\n", size);
		return -EINVAL;
		}

		if ((base & (phys_addr_t)(size - 1)) != 0) {
		WARN(true, "Invalid MBus base/size: %pa len 0x%zx\n", &base,
		size);
		return -EINVAL;
		}

		ctrl = ((size - 1) & WIN_CTRL_SIZE_MASK) \|
		(attr << WIN_CTRL_ATTR_SHIFT) \|
		(target << WIN_CTRL_TGT_SHIFT) \|
		@@ -413,6 +425,10 @@ static int mvebu_devs_debug_show(struct seq_file seq, void v)
		win, (unsigned long long)wbase,
		(unsigned long long)(wbase + wsize), wtarget, wattr);

		if (!is_power_of_2(wsize) \|\|
		((wbase & (u64)(wsize - 1)) != 0))
		seq_puts(seq, " (Invalid base/size!!)");

		if (win < mbus->soc->num_remappable_wins) {
		seq_printf(seq, " (remap %016llx)\n",
		(unsigned long long)wremap);

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