From: Alex Elder elder@linaro.org
[ Upstream commit 2d65ed76924bc772d3974b0894d870b1aa63b34a ]
In ipa_cmd_register_write_valid() we verify that values we will supply to a REGISTER_WRITE IPA immediate command will fit in the fields that need to hold them. This patch fixes some issues in that function and ipa_cmd_register_write_offset_valid().
The dev_err() call in ipa_cmd_register_write_offset_valid() has some printf format errors: - The name of the register (corresponding to the string format specifier) was not supplied. - The IPA base offset and offset need to be supplied separately to match the other format specifiers. Also make the ~0 constant used there to compute the maximum supported offset value explicitly unsigned.
There are two other issues in ipa_cmd_register_write_valid(): - There's no need to check the hash flush register for platforms (like IPA v4.2) that do not support hashed tables - The highest possible endpoint number, whose status register offset is computed, is COUNT - 1, not COUNT.
Fix these problems, and add some additional commentary.
Signed-off-by: Alex Elder elder@linaro.org Signed-off-by: David S. Miller davem@davemloft.net Signed-off-by: Sasha Levin sashal@kernel.org --- drivers/net/ipa/ipa_cmd.c | 32 ++++++++++++++++++++++++-------- 1 file changed, 24 insertions(+), 8 deletions(-)
diff --git a/drivers/net/ipa/ipa_cmd.c b/drivers/net/ipa/ipa_cmd.c index 002e51448510..eb65a11e33ea 100644 --- a/drivers/net/ipa/ipa_cmd.c +++ b/drivers/net/ipa/ipa_cmd.c @@ -1,7 +1,7 @@ // SPDX-License-Identifier: GPL-2.0
/* Copyright (c) 2012-2018, The Linux Foundation. All rights reserved. - * Copyright (C) 2019-2020 Linaro Ltd. + * Copyright (C) 2019-2021 Linaro Ltd. */
#include <linux/types.h> @@ -244,11 +244,15 @@ static bool ipa_cmd_register_write_offset_valid(struct ipa *ipa, if (ipa->version != IPA_VERSION_3_5_1) bit_count += hweight32(REGISTER_WRITE_FLAGS_OFFSET_HIGH_FMASK); BUILD_BUG_ON(bit_count > 32); - offset_max = ~0 >> (32 - bit_count); + offset_max = ~0U >> (32 - bit_count);
+ /* Make sure the offset can be represented by the field(s) + * that holds it. Also make sure the offset is not outside + * the overall IPA memory range. + */ if (offset > offset_max || ipa->mem_offset > offset_max - offset) { dev_err(dev, "%s offset too large 0x%04x + 0x%04x > 0x%04x)\n", - ipa->mem_offset + offset, offset_max); + name, ipa->mem_offset, offset, offset_max); return false; }
@@ -261,12 +265,24 @@ static bool ipa_cmd_register_write_valid(struct ipa *ipa) const char *name; u32 offset;
- offset = ipa_reg_filt_rout_hash_flush_offset(ipa->version); - name = "filter/route hash flush"; - if (!ipa_cmd_register_write_offset_valid(ipa, name, offset)) - return false; + /* If hashed tables are supported, ensure the hash flush register + * offset will fit in a register write IPA immediate command. + */ + if (ipa->version != IPA_VERSION_4_2) { + offset = ipa_reg_filt_rout_hash_flush_offset(ipa->version); + name = "filter/route hash flush"; + if (!ipa_cmd_register_write_offset_valid(ipa, name, offset)) + return false; + }
- offset = IPA_REG_ENDP_STATUS_N_OFFSET(IPA_ENDPOINT_COUNT); + /* Each endpoint can have a status endpoint associated with it, + * and this is recorded in an endpoint register. If the modem + * crashes, we reset the status endpoint for all modem endpoints + * using a register write IPA immediate command. Make sure the + * worst case (highest endpoint number) offset of that endpoint + * fits in the register write command field(s) that must hold it. + */ + offset = IPA_REG_ENDP_STATUS_N_OFFSET(IPA_ENDPOINT_COUNT - 1); name = "maximal endpoint status"; if (!ipa_cmd_register_write_offset_valid(ipa, name, offset)) return false;