From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id E58C01A0DF2; Wed, 5 Jun 2024 12:02:50 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1717588971; cv=none; b=ceqo047/7x+hvRG3xZ109/5etT+1Lih5P6kJoddQ3Eps+PtiMpJ20JLARGqyHk6J5SxjcYf3vupynldWYTV7Q1BEKKhZXBis5D32AzmkHYTojZDBUCCFaDwFeER+Q1hm9EsMEfaurD24belbe+6rauZkEPMQLSWubBrOZG2JAog= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1717588971; c=relaxed/simple; bh=miWF0EhdzQHWTZJygReqmuJhFVGFLmr1odB17pUnQiI=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=Z3Y/fVVd7rAMgRxj3xuQnVGqQheJYShXjHyUa9YtZiKRb7HLGT0iYuhAElqFlAzDy3s8i78ewUH/jcRamZWTqHX79Nz7PEycgDdyq/6DCxGPW6YhFw+5vriN/2AhItrKaeQAFuDwOm2u2FwXmQhNIGeHsKUIPG1Af+Au7c5YY+k= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=aANO43HV; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="aANO43HV" Received: by smtp.kernel.org (Postfix) with ESMTPSA id A8A95C32781; Wed, 5 Jun 2024 12:02:49 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1717588970; bh=miWF0EhdzQHWTZJygReqmuJhFVGFLmr1odB17pUnQiI=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=aANO43HV9DyW3f/OEo3WT5+83Hrg7AVWn3pA0tUHN49URImuO46XukApc0wQuXNG+ PsaIiQCLg4f6QEsy+wkjS16ShZUpOwIhHgP8CXU3dexWfg8yL7WivPOuKXept83xxN 0WKgg8lPpoPGPWi+3si1ozJ9wuG07wsYz8Pwsd+1+s9J2zxeMNHCrwXYdDB67Awugp r7Gw4ajHpp4XbUfyeE6t/oQu8AVI5G4Xr/Y1RSQW/qncLMmHlLSuCYgoLaER1Humc7 ZbmNbZwjLQxtYN1lT7jWuilloEXs81S5errhdycXhXJ5rXTgJ0l1hUZTyfkwygIaTE 5ZZ7KhzcDLSFw== From: Sasha Levin To: linux-kernel@vger.kernel.org, stable@vger.kernel.org Cc: Witold Sadowski , Mark Brown , Sasha Levin , linux-spi@vger.kernel.org Subject: [PATCH AUTOSEL 6.9 17/23] spi: cadence: Ensure data lines set to low during dummy-cycle period Date: Wed, 5 Jun 2024 08:02:00 -0400 Message-ID: <20240605120220.2966127-17-sashal@kernel.org> X-Mailer: git-send-email 2.43.0 In-Reply-To: <20240605120220.2966127-1-sashal@kernel.org> References: <20240605120220.2966127-1-sashal@kernel.org> Precedence: bulk X-Mailing-List: linux-spi@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 X-stable: review X-Patchwork-Hint: Ignore X-stable-base: Linux 6.9.3 Content-Transfer-Encoding: 8bit From: Witold Sadowski [ Upstream commit 4a69c1264ff41bc5bf7c03101ada0454fbf08868 ] During dummy-cycles xSPI will switch GPIO into Hi-Z mode. In that dummy period voltage on data lines will slowly drop, what can cause unintentional modebyte transmission. Value send to SPI memory chip will depend on last address, and clock frequency. To prevent unforeseen consequences of that behaviour, force send single modebyte(0x00). Modebyte will be send only if number of dummy-cycles is not equal to 0. Code must also reduce dummycycle byte count by one - as one byte is send as modebyte. Signed-off-by: Witold Sadowski Link: https://msgid.link/r/20240529074037.1345882-2-wsadowski@marvell.com Signed-off-by: Mark Brown Signed-off-by: Sasha Levin --- drivers/spi/spi-cadence-xspi.c | 20 +++++++++++++++----- 1 file changed, 15 insertions(+), 5 deletions(-) diff --git a/drivers/spi/spi-cadence-xspi.c b/drivers/spi/spi-cadence-xspi.c index 8648b8eb080dc..cdce2e280f663 100644 --- a/drivers/spi/spi-cadence-xspi.c +++ b/drivers/spi/spi-cadence-xspi.c @@ -145,6 +145,9 @@ #define CDNS_XSPI_STIG_DONE_FLAG BIT(0) #define CDNS_XSPI_TRD_STATUS 0x0104 +#define MODE_NO_OF_BYTES GENMASK(25, 24) +#define MODEBYTES_COUNT 1 + /* Helper macros for filling command registers */ #define CDNS_XSPI_CMD_FLD_P1_INSTR_CMD_1(op, data_phase) ( \ FIELD_PREP(CDNS_XSPI_CMD_INSTR_TYPE, (data_phase) ? \ @@ -157,9 +160,10 @@ FIELD_PREP(CDNS_XSPI_CMD_P1_R2_ADDR3, ((op)->addr.val >> 24) & 0xFF) | \ FIELD_PREP(CDNS_XSPI_CMD_P1_R2_ADDR4, ((op)->addr.val >> 32) & 0xFF)) -#define CDNS_XSPI_CMD_FLD_P1_INSTR_CMD_3(op) ( \ +#define CDNS_XSPI_CMD_FLD_P1_INSTR_CMD_3(op, modebytes) ( \ FIELD_PREP(CDNS_XSPI_CMD_P1_R3_ADDR5, ((op)->addr.val >> 40) & 0xFF) | \ FIELD_PREP(CDNS_XSPI_CMD_P1_R3_CMD, (op)->cmd.opcode) | \ + FIELD_PREP(MODE_NO_OF_BYTES, modebytes) | \ FIELD_PREP(CDNS_XSPI_CMD_P1_R3_NUM_ADDR_BYTES, (op)->addr.nbytes)) #define CDNS_XSPI_CMD_FLD_P1_INSTR_CMD_4(op, chipsel) ( \ @@ -173,12 +177,12 @@ #define CDNS_XSPI_CMD_FLD_DSEQ_CMD_2(op) \ FIELD_PREP(CDNS_XSPI_CMD_DSEQ_R2_DCNT_L, (op)->data.nbytes & 0xFFFF) -#define CDNS_XSPI_CMD_FLD_DSEQ_CMD_3(op) ( \ +#define CDNS_XSPI_CMD_FLD_DSEQ_CMD_3(op, dummybytes) ( \ FIELD_PREP(CDNS_XSPI_CMD_DSEQ_R3_DCNT_H, \ ((op)->data.nbytes >> 16) & 0xffff) | \ FIELD_PREP(CDNS_XSPI_CMD_DSEQ_R3_NUM_OF_DUMMY, \ (op)->dummy.buswidth != 0 ? \ - (((op)->dummy.nbytes * 8) / (op)->dummy.buswidth) : \ + (((dummybytes) * 8) / (op)->dummy.buswidth) : \ 0)) #define CDNS_XSPI_CMD_FLD_DSEQ_CMD_4(op, chipsel) ( \ @@ -351,6 +355,7 @@ static int cdns_xspi_send_stig_command(struct cdns_xspi_dev *cdns_xspi, u32 cmd_regs[6]; u32 cmd_status; int ret; + int dummybytes = op->dummy.nbytes; ret = cdns_xspi_wait_for_controller_idle(cdns_xspi); if (ret < 0) @@ -365,7 +370,12 @@ static int cdns_xspi_send_stig_command(struct cdns_xspi_dev *cdns_xspi, memset(cmd_regs, 0, sizeof(cmd_regs)); cmd_regs[1] = CDNS_XSPI_CMD_FLD_P1_INSTR_CMD_1(op, data_phase); cmd_regs[2] = CDNS_XSPI_CMD_FLD_P1_INSTR_CMD_2(op); - cmd_regs[3] = CDNS_XSPI_CMD_FLD_P1_INSTR_CMD_3(op); + if (dummybytes != 0) { + cmd_regs[3] = CDNS_XSPI_CMD_FLD_P1_INSTR_CMD_3(op, 1); + dummybytes--; + } else { + cmd_regs[3] = CDNS_XSPI_CMD_FLD_P1_INSTR_CMD_3(op, 0); + } cmd_regs[4] = CDNS_XSPI_CMD_FLD_P1_INSTR_CMD_4(op, cdns_xspi->cur_cs); @@ -375,7 +385,7 @@ static int cdns_xspi_send_stig_command(struct cdns_xspi_dev *cdns_xspi, cmd_regs[0] = CDNS_XSPI_STIG_DONE_FLAG; cmd_regs[1] = CDNS_XSPI_CMD_FLD_DSEQ_CMD_1(op); cmd_regs[2] = CDNS_XSPI_CMD_FLD_DSEQ_CMD_2(op); - cmd_regs[3] = CDNS_XSPI_CMD_FLD_DSEQ_CMD_3(op); + cmd_regs[3] = CDNS_XSPI_CMD_FLD_DSEQ_CMD_3(op, dummybytes); cmd_regs[4] = CDNS_XSPI_CMD_FLD_DSEQ_CMD_4(op, cdns_xspi->cur_cs); -- 2.43.0